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Frequently Asked Questions

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Abnormal sperm morphology: What does it mean?

Abnormal sperm morphology may be a contributing factor in male infertility.

Acetyl-L-carnitine: Can it relieve MS fatigue?

Some research suggests that acetyl-L-carnitine may improve fatigue associated with multiple sclerosis, but more study is needed.

Acid reflux and GERD: The same thing?

Acid reflux and GERD are closely related, but the terms aren't necessarily interchangeable.

Acne scars: What's the best treatment?

Various procedures can improve acne scars, but no single treatment is best for everyone.

Acute bronchitis: Is it contagious?

Most cases of acute bronchitis are caused by viruses and are contagious. Learn ways to reduce your risk of catching viruses that can cause bronchitis.

Acute sinusitis: Do over-the-counter treatments help?

Medicine you can get without a prescription may give some relief from acute sinusitis symptoms.

Adrenal fatigue: What causes it?

Adrenal fatigue is a term used to describe a group of symptoms that aren't specific. It's not an official medical diagnosis.

Adult bed-wetting: A concern?

Adult bed-wetting is uncommon and requires evaluation by a doctor. Learn about possible causes.

Air travel during pregnancy: Is it safe?

Consider these guidelines if you need to fly while you're pregnant.

Air travel with infant: Is it safe?

Planning for air travel with an infant? Know how air travel can affect a newborn's ears and breathing, and what you can do to keep your baby comfortable.

Albuterol side effects: Can I avoid them?

Albuterol side effects — Managing reactions to quick-relief asthma medication.

Alcohol: Does it affect blood pressure?

Drinking too much alcohol can raise blood pressure to unhealthy levels.

Alkaline water: Better than plain water?

Health claims about alkaline water abound, but plain water is usually best.

Allergy medications and pregnancy: What's safe?

Find out what medicines can help you manage allergies while you're pregnant.

Alzheimer's and dementia: What's the difference?

The terms 'Alzheimer's disease' and 'dementia' are often used to mean the same thing — but here's the real difference between them.

Alzheimer's prevention: Does it exist?

Alzheimer's prevention: Strategies for staying physically and mentally fit may be most effective.

Ambien: Is dependence a concern?

Zolpidem (Ambien) for insomnia is generally safe in the short term, but some people who take it may behave dangerously, such as driving while not awake.

Ankle swelling during pregnancy: What helps?

Try these prevention and treatment tips for ankle swelling during pregnancy.

Antibiotics and alcohol

Alcohol doesn't lower the effectiveness of most antibiotics. But it's still a good idea to avoid alcohol while taking antibiotics.

Antibiotics and pregnancy: What's safe?

Learn about common types of antibiotics used during pregnancy and their safety.

Antidepressant withdrawal: Is there such a thing?

Antidepressant withdrawal is possible if you stop taking an antidepressant abruptly — but it's generally preventable.

Antidepressants and alcohol: What's the concern?

Combining antidepressants and alcohol can worsen depression and cause other problems.

Antidepressants and weight gain: What causes it?

An antidepressant isn't always a direct cause of weight gain. Learn the other causes of weight gain when taking antidepressants and how to manage weight.

Antidepressants: Can they stop working?

Antidepressants: Reasons treatment stops working.

Antidepressants: Which cause the fewest sexual side effects?

Sexual side effects are common with antidepressants in both men and women, but there are options to prevent or reduce such side effects.

Anxiety: A cause of high blood pressure?

Anxiety can cause dramatic, temporary increases in blood pressure.

Aortic calcification: An early sign of heart valve problems?

Aortic valve calcification — once thought a harmless condition — may be a sign of heart valve disease.

Apple cider vinegar for weight loss

Proponents tout apple cider vinegar as a weight-loss aid, but there's little proof that it works.

Arcus senilis: A sign of high cholesterol?

With this condition, older adults develop a gray arc around the cornea of the eyes.

Artificial sweeteners: Any effect on blood sugar?

Artificial sweeteners, also called sugar substitutes, offer the sweetness of sugar without the calories.

Artificial tears: How to select eye drops for dry eyes

Not all eye drops are the same. Here's what to consider when choosing artificial tears for dry eyes.

Aspirin allergy: What are the symptoms?

An aspirin allergy or sensitivity can cause serious symptoms.

Aspirin during pregnancy: Is it safe?

A Mayo Clinic specialist explains what you need to know about taking aspirin if you're pregnant.

Asthma and acid reflux: Are they linked?

A Mayo Clinic expert discusses how acid reflux can make asthma worse.

Asthma diet: Does what you eat make a difference?

Can what you eat affect your asthma? Learn how healthy eating habits may reduce asthma symptoms.

Atypical cells: Are they cancer?

Atypical cells appear abnormal, but they aren't necessarily cancerous.

Autism spectrum disorder and digestive symptoms

Children with autism spectrum disorder often have other health issues, including problems related to digestion.

Avulsion fracture: How is it treated?

Surgery is rarely needed to reattach a small chunk of bone when it gets pulled away from the main part of the bone by a tendon or ligament.

Baby fat: When is it cause for concern?

Find out when your baby's weight might be of concern and how to promote a healthy weight.

Baby poop: What to expect

Infant stool can have various colors and textures. Know what to expect in your newborn's diapers.

Baby teeth: When do children start losing them?

Losing baby teeth is a major childhood milestone. Find out what to expect.

Bacterial vs. viral infections: How do they differ?

Understand the differences between bacterial and viral infections.

Beta blockers: Do they cause weight gain?

Weight gain can occur as a side effect of some of these medications used for high blood pressure and other conditions.

Beta blockers: How do they affect exercise?

If you take this medicine, you may need to change your target heart rate during exercise.

Bioidentical hormones: Are they safer?

There's no evidence that bioidentical hormones are safer than standard hormone therapy for menopause.

Bipolar disorder and alcoholism: Are they related?

These disorders often occur together, and they can be a dangerous mix. Having both conditions makes mood swings, depression, violence and suicide more likely.

Bipolar disorder in children: Is it possible?

Bipolar disorder in children and teenagers is possible. Finding it early and treating it can help.

Bipolar medications and weight gain

Some medications used to treat bipolar disorder can increase your appetite or cause changes in metabolism leading to weight gain.

Bipolar treatment: Are bipolar I and bipolar II treated differently?

Bipolar I and bipolar II are different disorders, but treatment is similar.

Birth control pills: Harmful in early pregnancy?

If you took birth control pills before you knew you were pregnant, the risks of birth defects are low.

Birth control: Can preejaculation fluid cause pregnancy?

This possible cause of pregnancy makes withdrawal a method of birth control you cannot rely on.

Bladder infection in men

Although women are more likely to get bladder infections, men can get them, too. Learn about signs and symptoms and what could put you at risk.

Bladder outlet obstruction: Causes in men?

Find out more about the causes of male bladder outlet obstruction and possible next steps.

Bleeding after hysterectomy: What can I expect?

Light vaginal bleeding after hysterectomy is common; it may occur for several days or several weeks.

Bleeding after menopause: A concern?

It's unusual to bleed from the vagina after menopause. Learn what health problems can cause it and why you need to see your health care provider.

Blighted ovum: What causes it?

A Mayo Clinic specialist explains what's behind this type of early pregnancy loss.

Blood clots during menstruation: A concern?

Blood clots during menstrual periods aren't always a cause for a concern. But passing large clots may be a sign that something is wrong.

Blood glucose monitors: What factors affect accuracy?

Consider these factors when measuring blood sugar levels with blood glucose monitors.

Blood pressure cuff: Does size matter?

Accurate blood pressure readings depend on the proper size blood pressure cuff.

Blood pressure medication: Still necessary if I lose weight?

Losing weight may reduce or end the need for blood pressure medicine.

Blood pressure medications: Can they raise my triglycerides?

Learn which blood pressure medicines might raise triglyceride levels.

Blood pressure readings: Why higher at home?

Blood pressure that consistently measures higher outside a medical office is called masked hypertension.

Blood pressure: Can it be higher in one arm?

A small difference in blood pressure readings between arms usually isn't a worry. But a large difference can be a warning sign of a health problem.

Blood pressure: Does it have a daily pattern?

Like many body functions, blood pressure has a daily pattern. Find out more.

Blood pressure: Is it affected by cold weather?

Blood pressure generally is higher in the winter than in the summer. Discover why.

Blood sugar levels can fluctuate for many reasons

Unexplained changes in blood sugar levels can be the result of illness, injury, stress and hormone changes.

Blood thinners: Can I still get blood clots?

These medications must be taken exactly as directed to prevent blood clots.

Breast implants and cancer: Any connection?

Concerned about a link between breast implants and cancer? Get the facts.

Breastfeeding and alcohol: Is it OK to drink?

Breastfeeding and alcohol don't mix well. A Mayo Clinic specialist discusses how alcohol affects breast milk.

Breastfeeding strike: Why do babies refuse to nurse?

Understand why babies sometimes refuse to breastfeed and what you can do about it.

Bulging disk vs. herniated disk: What's the difference?

Compared with a bulging disk, a herniated disk is more likely to cause pain because it protrudes farther and is more likely to compress nerve roots.

Bump on the head: When is it a serious head injury?

Even a minor injury to the scalp or forehead can cause a large lump. Find out when it's time to see a healthcare professional.

Butter vs. margarine: Which is better for my heart?

Margarine usually tops butter for heart health. But not all margarines are created equal.

CA 125 test: A screening test for ovarian cancer?

Learn why health care providers generally don't recommend a CA 125 test for ovarian cancer screening.

CBD: Safe and effective?

Interested in using CBD? Here's what you need to know about the risks and benefits of using this drug.

COVID-19 and pets: Can dogs and cats get COVID-19?

Find out how COVID-19 can affect dogs and cats, what you can do to protect your pet, and how to care for your pet if it becomes sick.

COVID-19 drugs: Are there any that work?

Many treatments are being studied for COVID-19. Only one drug has been approved — an antiviral drug called remdesivir.

COVID-19 infections by race: What's behind the health disparities?

Understand how underlying health problems, the places where people live and work, and racism can affect who becomes severely ill with COVID-19.

COVID-19 vaccine: Should I reschedule my mammogram?

Swollen lymph nodes caused by the COVID-19 vaccine can look like breast cancer on a mammogram. Find out what to do if you've got a mammogram scheduled.

COVID-19 variants: What's the concern?

The virus that causes COVID-19 has changed over time, which has affected prevention, diagnosis and treatment of COVID-19.

Caffeine: Does it affect blood sugar?

For some people with diabetes, one cup of coffee may raise or lower blood sugar. Learn how caffeine can affect blood sugar.

Caffeine: How does it affect blood pressure?

Caffeine can temporarily increase blood pressure, but its long-term effects on blood pressure are unclear.

Caffeine: Is it dehydrating or not?

Caffeinated drinks usually won't dehydrate you, but water is still your best option.

Calcium supplements: A risk factor for heart attack?

Learn about the possible link between calcium supplements and heart attacks.

Calcium supplements: Do they interfere with blood pressure drugs?

In large amounts, calcium supplements may interfere with certain blood pressure medications.

Calcium supplements: When should they be taken?

Timing matters when taking these supplements. Learn how to take them.

Can vaginal tears during childbirth be prevented?

Learn what you can do to help lower the risk of vaginal tears during childbirth.

Can vitamin D protect against coronavirus disease 2019 (COVID-19)?

Find out what the research says about vitamin D and coronavirus disease 2019 (COVID-19).

Can vitamins help prevent a heart attack?

Study results are mixed on whether vitamins can prevent heart disease. Find out more.

Can whole-grain foods lower blood pressure?

Find out if eating whole-grain foods can lower blood pressure.

Can you recommend a diet after gallbladder removal?

Should you follow a special diet to prevent problems after gallbladder surgery?

Candida cleanse diet: What does it treat?

Candida cleanse diets that replace processed food with fresh foods improve health but don't necessarily stop yeast overgrowth.

Car sickness in children: Can I prevent it?

Carefully planned pre-trip meals, air ventilation and distractions might help prevent car sickness in children.

Cardiac asthma: What causes it?

Wheezing isn't always due to true asthma. Sometimes it's a sign of heart failure. Know the difference.

Carpal tunnel exercises: Can they relieve symptoms?

Carpal tunnel exercises may be helpful, but they aren't used alone.

Cellulitis infection: Is it contagious?

Cellulitis — a common, potentially serious bacterial skin infection — is not directly contagious.

Cellulitis: How to prevent recurrent episodes

Learn to treat and prevent recurrent cellulitis.

Cervical cysts: Can they be cancerous?

Cervical cysts usually aren't cancerous. Some types of cervical cysts are so common that they're considered a normal feature of cervical anatomy.

Cervical dysplasia: Is it cancer?

Learn what to expect if a Pap test shows cells that look different from typical cervical cells. Follow-up tests might include HPV testing and colposcopy.

Cervical length: Why does it matter during pregnancy?

If cervical length during pregnancy shortens too soon, there might be an increased risk of preterm labor.

Chelation therapy for heart disease: Does it work?

Learn more about this debated treatment for heart disease.

Chemotherapy and sex: Is sexual activity OK during treatment?

Chemotherapy and sex aren't mutually exclusive, as long as you're feeling up to it.

Chemotherapy side effects: A cause of heart disease?

Chemotherapy side effects may include a risk of heart problems, including weakened heart muscle (cardiomyopathy) and heart rhythm problems (arrhythmia).

Chickenpox and pregnancy: What are the concerns?

Understand the risks posed by chickenpox during pregnancy.

Child growth: Can you predict adult height?

Concerned about your child's growth? Find out how you can estimate your child's adult height.

Cholesterol level: Can it be too low?

A high cholesterol level is unhealthy — rarely, very low cholesterol may pose risks, too.

Cholesterol ratio or non-HDL cholesterol: Which is most important?

Non-HDL cholesterol may be more important than cholesterol ratio.

Cholesterol test kits: Are they accurate?

Home cholesterol test kits are often as accurate as the test a health care professional uses, but the quality of results can depend on how well you follow the directions for the test.

Chronic bladder infection: Is there a cure?

Chronic bladder infection can be a painful, frustrating problem. Learn about causes and treatments.

Chronic diarrhea: A concern after gallbladder removal?

Diarrhea is fairly common after gallbladder removal. Find out what to expect.

Cigar smoking: Safer than cigarette smoking?

Despite what you might think, cigars aren't that different from cigarettes. Like cigarettes, cigars contain nicotine, tobacco and cancer-causing chemicals.

Clinical depression: What does that mean?

The term "clinical depression" means severe, persistent depression. It's also called major depression or major depressive disorder.

Coconut oil: Can it cure hypothyroidism?

This oil has been touted by some as a cure for hypothyroidism. Truth or hype?

Coconut water: Is it super hydrating?

This drink is promoted as "super hydrating." But is it really any better than plain water?

Coffee and health: What does the research say?

Has coffee gotten a bum rap? Can it be part of a healthy diet?

Coffee calories: Sabotaging your weight loss?

Plain coffee has only a few calories. But the calories jump up when you start adding extras.

Cold and flu viruses: How long can they live outside the body?

Some viruses are more resilient than you may think. Learn more about how they spread and how to protect yourself.

Cold or allergy: Which is it?

Although colds and seasonal allergies share some of the same symptoms, they are very different diseases. Learn how to tell the difference.

Cold symptoms: Does drinking milk increase phlegm?

Colds mean extra thick and sticky mucus, but dairy milk doesn't make phlegm worse.

Colloidal silver supplements: Are they safe?

Colloidal silver supplements are often promoted as cure-alls, but evidence of effectiveness is lacking. Side effects range from change in skin color to organ damage.

Colon cancer screening: At what age can you stop?

Some groups recommend people over 75 may consider stopping colon cancer screening. Not everyone agrees. Learn about your colon cancer screening options.

Colon cleansing: Is it helpful or harmful?

Get the facts before trying this technique that's popular among some alternative medicine practitioners who claim it has numerous health benefits.

Concussion in children: What are the symptoms?

Whether your child's concussion is mild or severe, allow time to recover.

Coping with anxiety: Can diet make a difference?

Coping with anxiety is a challenge. Eating habits may play a role.

Coping with pain after breast surgery

Pain is common after mastectomy and other breast cancer operations. Find out what causes it and learn about treatment options.

Coronary artery disease: Angioplasty or bypass surgery?

The best treatment for coronary artery disease depends on the circumstances.

Coronary artery spasm: Cause for concern?

This sudden, temporary squeezing of the muscles in an artery wall reduces blood flow to the heart. Know the causes and treatment.

Coronavirus: What is it and how can I protect myself?

Coronavirus disease 2019 (COVID-19) is caused by a virus that spreads between people. Find out how to protect yourself and those close to you.

Coughing more after quitting smoking: What's the deal?

If you cough more than usual after you give up cigarettes, find out what it might mean and when to call the doctor.

Craving and chewing ice: A sign of anemia?

Craving and chewing ice (pagophagia) is often associated with iron deficiency with or without anemia.

Curcumin: Can it slow cancer growth?

Some research suggests that curcumin may help prevent or treat cancer.

Degenerative changes in the spine: Is this arthritis?

Degenerative changes in the spine visible on X-rays indicate osteoarthritis of the spine.

Demyelinating disease: What can you do about it?

Understanding the causes and types of demyelinating disease, such as multiple sclerosis, can help guide treatment decisions and manage symptoms.

Dental floss vs. water flosser: Which is better?

Cleaning between your teeth every day is an important part of good oral health.

Denture care: How do I clean dentures?

Follow these best practices to keep your removable partial or full dentures clean, free from stains and comfortable.

Depression and anxiety: Can I have both?

Depression and anxiety commonly occur together and have similar treatments: counseling (psychotherapy) or medication, such as antidepressants, or both.

Detox foot pads: Do they really work?

Do detox foot pads really draw toxins out of your body while you sleep?

Diabetes and depression: Coping with the two conditions

Diabetes and depression can occur together. Here's what you need to know.

Diabetes diet: Should I avoid sweet fruits?

It's a common myth that you shouldn't eat certain foods if you have diabetes.

Diabetes foods: Can I substitute honey for sugar?

Generally, there's no advantage to substituting honey for sugar in a diabetes eating plan.

Diabetes treatment: Can cinnamon lower blood sugar?

Learn what cinnamon's role may be as part of a diabetes treatment plan.

Diabetes: How do I help protect my liver?

How to care for your liver if you have diabetes.

Did the definition of Alzheimer's disease change?

What the change in the research definition of Alzheimer's disease means for you.

Diet soda: How much is too much?

Diet soda may help you cut calories, but other low-calorie options abound.

Digestion: How long does it take?

Digestion takes about two to five days, depending on your system.

Discolored baby teeth: A cause for concern?

Baby teeth can become discolored for many reasons, including inadequate brushing, medications and illness.

Discolored semen: What does it mean?

Find out what causes discolored semen.

Diuretics and gout: What's the connection?

Diuretics and gout can be related because the medication may raise uric acid in your blood. It's usually possible to avoid this side effect, though.

Diuretics: A cause of low potassium?

These medications are commonly used to treat high blood pressure. A side effect of some diuretics is low potassium.

Diverticulitis: Can certain foods trigger an attack?

Contrary to popular belief, no specific foods are known to trigger diverticulitis attacks.

Do infrared saunas have any health benefits?

How is an infrared sauna different from a traditional sauna? Light provides the heat.

Do the benefits of vitamin C include improved mood?

You know vitamin C helps fight the common cold. But did you know that vitamin C might also help improve your mood?

Does atrial fibrillation run in families?

AFib is a common heart disorder. Sometimes it is inherited. Learn about all the risk factors.

Does older age increase the risk of atrial fibrillation?

Learn how the risk of getting this common heart rhythm condition can increase with age.

Does prickly pear cactus have health benefits?

Have you heard about prickly pear cactus? Find out about some surprising health benefits of this versatile plant.

Does soy really affect breast cancer risk?

Soy foods reduce the risk of breast cancer, but more research is needed to determine whether soy supplements are equally beneficial.

Does sunscreen expire?

Wondering whether sunscreen expires? Get the facts about how long sunscreen lasts.

Doppler ultrasound: What is it used for?

A Doppler ultrasound measures blood flow and pressure in blood vessels.

Drinking alcohol: Is it safe after hepatitis C cure?

Your hepatitis C infection has been cured, but is it safe to drink alcohol again?

Dry mouth treatment: Tips for controlling dry mouth

To ease dry mouth, chew sugar-free gum or suck on sugar-free hard candy to keep saliva flowing. Limit caffeine and don't use tobacco. Sip water regularly.

Early HIV symptoms: What are they?

Early signs of the disease can include fever, fatigue and swollen lymph glands. Learn more.

Early miscarriage: Is stress a factor?

Early miscarriage is usually caused by an abnormality with the baby — not maternal stress.

Eating the placenta: A good idea?

Despite claims of benefits, eating your placenta after giving birth can be harmful to you and your baby.

Ebola transmission: Can Ebola spread through the air?

Ebola virus: A Mayo Clinic expert explains how the virus spreads

Eczema bleach bath: Can it improve my symptoms?

A diluted bleach bath may help treat chronic eczema.

Eggs: Are they good or bad for my cholesterol?

Get the latest information about eggs, cholesterol and heart disease.

Ejection fraction: What does it measure?

This measurement, commonly taken during an echocardiogram, shows how well the heart is pumping. Know what results mean.

Elective abortion: Does it affect subsequent pregnancies?

Understand if an elective abortion can affect your fertility or future pregnancies.

Emerging treatments for multiple sclerosis

There is no cure for this disorder of the nervous system but promising research offers hope for new ways to slow and perhaps reverse the effects of this disease.

Enlarged prostate: Does diet play a role?

Lifestyle factors such as diet appear to play a role in benign prostatic hyperplasia (BPH). See what lifestyle changes may help with symptoms.

Enterovirus D68 and parechovirus: How can I protect my child?

Enterovirus D68 and parechovirus infections can lead to serious illness among children. Know the symptoms and what you can do.

Exercise and illness: Work out with a cold?

Play it smart. Ease up on exercise if you have a cold.

Exercise and multiple sclerosis

Reduce your multiple sclerosis symptoms through exercise.

Exercise: How much do I need every day?

Find out how much exercise you need and how to get it.

Extended-cycle birth control pills: Is spotting common?

Breakthrough bleeding is more common with continuous and extended-cycle birth control pills, but usually decreases with time.

Eye dilation: Necessary with every eye exam?

Eye dilation is part of a comprehensive eye exam. How often you need it depends on your age and health risks.

Fainting during urination (micturition syncope): What causes it?

Fainting during or immediately after urination, called micturition syncope, is a rare occurrence in healthy individuals.

Falling during pregnancy: Reason to worry?

Here's what to consider after a fall during pregnancy, including when to seek medical help.

Fallopian tubes: Is pregnancy possible with only one?

Pregnancy may be possible with one fallopian tube.

Fasting diet: Can it improve my heart health?

Periodically following a fasting diet may have heart-health benefits. Find out more.

Fear of public speaking: How can I overcome it?

Learn tips to become a more-confident public speaker

Female orgasm: No climax with vaginal penetration?

Not all women have orgasms with vaginal penetration during sex. Most women need stimulation of the clitoris to climax.

Fiber supplements: Safe to take every day?

Fiber supplements are one way to add fiber to the diet. Here are some tips for using them safely.

Flaxseed: Is ground better than whole?

Nutrition experts recommend ground flaxseed over whole flaxseed. Find out why.

Flu mask: Should I wear one?

Influenza masks and hand hygiene might help protect healthcare workers from flu (influenza).

Flu shot in pregnancy: Is it safe?

Will you be pregnant during flu season? A flu shot is safe — and it protects both you and your baby.

Flu shot: Will it prevent the stomach flu?

The flu shot protects against influenza, which is different from the stomach flu, also called gastroenteritis.

Flu shots for kids: Does my child need a flu shot?

Know the latest recommendations for children's flu vaccines.

Flu symptoms: Should I see my doctor?

See a healthcare professional if you are at high risk for complications from flu.

Flu vaccine: Safe for people with egg allergy?

If you have egg allergy, you still may be able to receive the flu vaccine.

Foamy urine: What does it mean?

Persistently foamy urine can be a sign of protein in your urine (proteinuria) and could be an indicator of kidney disease.

Food allergy vs. food intolerance: What's the difference?

Might you have to swear off milkshakes for good? Follow the symptom clues to find out whether you possibly have a food allergy or a food intolerance.

Food poisoning: How long can you safely keep leftovers?

Prevent food poisoning with these food safety tips for handling and reheating leftover food.

Foot swelling during air travel: A concern?

Swelling of the leg or foot while flying is common and usually harmless.

Free blood pressure machines: Are they accurate?

Results from free blood pressure monitoring machines aren't always accurate.

Frequent sex: Does it protect against prostate cancer?

Some studies have suggested that frequent ejaculation may reduce the risk of prostate cancer. But other research hasn't supported this idea.

Frontal fibrosing alopecia

This type of receding hairline, which primarily affects older women, is treatable. The earlier you talk with your doctor about it, the better your chance of preventing permanent baldness.

Fructose intolerance: Which foods to avoid?

Fructose is a sugar found naturally in fruits, fruit juices, some vegetables and honey. Learn which foods to avoid if you have fructose intolerance.

Fundal height: An accurate sign of fetal growth?

Understand how fundal height is measured and what it means.

GERD: Can certain medications make it worse?

Certain medicines can make symptoms of gastroesophageal reflux disease (GERD) worse. Learn more.

GLP-1 agonists: Diabetes drugs and weight loss

Noninsulin drugs for diabetes improve blood sugar control and may also support weight loss.

Gallbladder cleanse: A 'natural' remedy for gallstones?

A gallbladder cleanse is a popular alternative remedy for gallstones. But does it work?

Gallbladder polyps: Can they be cancerous?

The size of gallbladder polyps can be a useful predictor of whether they're cancerous.

Genital herpes: Can you get it from a toilet seat?

It is nearly impossible to get genital herpes from a toilet seat.

Glucosamine: Does it protect cartilage in osteoarthritis?

Glucosamine manufacturers claim their products slow or stop cartilage damage in osteoarthritis.

Glycemic index: A helpful tool for diabetes?

Some people with diabetes use the glycemic index as a guide in selecting foods.

Grapefruit: Beware of dangerous medication interactions

Some medicines don't mix with grapefruit and other citrus fruits. Learn what's safe.

Grass-fed beef: What are the heart-health benefits?

Grass-fed beef may have heart-health benefits that conventional beef doesn't. Find out more.

HCG diet: Is it safe and effective?

Is the HCG diet a safe way to shed pounds?

HER2-positive breast cancer: What is it?

HER2-positive breast cancer tends to be more aggressive than other types of breast cancer. Treatments that target HER2 are very effective.

HPV infection: A cause of cancer in men?

Learn what types of cancer HPV can cause in men and how you can reduce your risk.

Hand swelling during exercise: A concern?

This condition is a common problem, but rarely serious enough to disrupt your routine.

Headaches during pregnancy: What's the best treatment?

Headaches during pregnancy are common. Here's help easing the pain.

Heart attack prevention: Should I avoid secondhand smoke?

It's possible that secondhand smoke can irritate the arteries and increase the risk of a heart attack.

Heart cancer: Is there such a thing?

Although heart tumors do occur, the vast majority of them are noncancerous (benign).

Heart failure and sex: Is it safe?

Many people with heart failure worry that sex might harm their hearts. How do you know when it's OK to be intimate? Cardiac rehab and counseling can help.

Heart rate: What's normal?

A normal resting heart rate for adults ranges from 60 to 100 beats per minute. A heart rate above or below that may signal a problem.

Heartburn medicines and B-12 deficiency

Acid-controlling medications may do more than prevent heartburn. They may also interfere with vitamin B-12 absorption.

Heavy periods: Can folic acid help?

Heavy periods may cause iron deficiency anemia. Folic acid supplements can't treat that.

Hemorrhoids during pregnancy: What's the best treatment?

Know how to relieve painful, swollen veins in the anus and rectum during pregnancy.

Hepatitis C: How common is sexual transmission?

Although hepatitis C is highly contagious, the risk of sexual transmission is very low.

Hepatitis C: What happens in end-stage liver disease?

End-stage complications of hepatitis C include liver failure and liver cancer.

Herbal treatment for anxiety: Is it effective?

Herbal treatment for anxiety: A Mayo Clinic expert discusses safety and effectiveness.

High blood pressure and cold remedies: Which are safe?

Among cold medicines, decongestants cause the most concern for people who have high blood pressure.

High cholesterol in children: How is it treated?

High cholesterol in children can lead to narrowed and hardened arteries, increasing the risk of heart disease later in life.

High-dose flu vaccines: How are they different from other flu vaccines?

High-dose flu vaccines are flu vaccines for older people.

High-dose vitamin C: Can it kill cancer cells?

High-dose vitamin C has been touted by some as an effective alternative cancer treatment.

High-protein diets: Are they safe?

Considering a high-protein diet for weight loss? Understand the precautions first.

Hodgkin's vs. non-Hodgkin's lymphoma: What's the difference?

Learn how types of lymphomas are determined using lab tests to examine cancer cells.

Honey: An effective cough remedy?

A study in children with the common cold suggests that honey may help calm coughs.

Hookah smoking: Is it safer than cigarette smoking?

This habit isn't safer than smoking cigarettes. Find out why.

How do COVID-19 antibody tests differ from diagnostic tests?

Antibody testing determines if you had COVID-19 (coronavirus) infection in the past. It differs from testing to diagnose if you currently have COVID-19.

How many hours of sleep are enough?

Wonder how many hours of sleep are enough? A Mayo Clinic specialist offers guidelines.

How to heal cracked heels

Learn self-care tips for healing cracked heels.

How to heal cracked skin at thumb tip

Learn how to treat the tiny, painful cracks that can form on the thumb tip when your skin is very dry.

How to track saturated fat

Knowing how much saturated fat is in the foods you eat can help you meet your health and nutrition goals.

How to treat a piercing site infection

Learn what you can do at home if your ear new piercing becomes infected.

How to treat baby eczema

Learn simple remedies to easing your baby's discomfort from the pain and irritation of this skin rash.

Hyperinflated lungs: What does it mean?

If you can’t breathe out well, as in COPD, air may get trapped inside your lungs. As you breathe in more air over time, your lungs get too big and stiff.

Hyperinsulinemia: Is it diabetes?

Hyperinsulinemia often is associated with type 2 diabetes.

Hypertensive crisis: What are the symptoms?

A sudden rise in blood pressure over 180/120 mm Hg is considered a medical emergency, or crisis. It can lead to a stroke. Know the symptoms.

Hypothyroidism and infertility: Any connection?

For women, there's sometimes a link between having an underactive thyroid gland (hypothyroidism) and infertility.

Hypothyroidism diet: Can certain foods increase thyroid function?

There's no evidence that eating or avoiding certain foods will help the thyroid work better in people with underactive thyroid.

Hypothyroidism symptoms: Can hypothyroidism cause eye problems?

Hypothyroidism symptoms can vary, but eye problems aren't usually a concern.

Hypothyroidism: Can calcium supplements interfere with treatment?

Calcium supplements can interfere with how the body absorbs medications used to treat hypothyroidism.

Hypothyroidism: Can it cause peripheral neuropathy?

Hypothyroidism can cause damage to peripheral nerves and can lead to conditions such as carpal tunnel syndrome.

Hypothyroidism: Does it cause joint pain?

Hypothyroidism can cause muscle and joint problems, such as pain and stiffness.

Hypothyroidism: Should I take iodine supplements?

Although iodine deficiency can cause hypothyroidism, this deficiency is rare in the United States.

Implantation bleeding: Common in early pregnancy?

Implantation bleeding is a common early pregnancy symptom. Understand why it happens.

Induced lactation: Can I breastfeed my adopted baby?

With time and dedication, breastfeeding without pregnancy (induced lactation) might be possible.

Infant constipation: How is it treated?

Worried about infant constipation? A Mayo Clinic specialist explains how to treat it.

Infant growth: What's normal?

Infant growth rates depend on various factors. Consider what's typical during baby's first year.

Insomnia: How do I stay asleep?

Waking up in the middle of the night and not being able to get back to sleep is a common form of insomnia. Here's how to fall asleep again.

Intermittent fasting: What are the benefits?

Intermittent fasting isn't new, but it's gaining followers. What's the appeal?

Is a home sperm test useful?

Using a home sperm test to check your fertility may not provide a clear answer.

Is depression a factor in rheumatoid arthritis?

Depression is common in people with rheumatoid arthritis. If it isn't treated, depression may contribute to worsening of rheumatoid arthritis symptoms.

Isolated systolic hypertension: A health concern?

Both the top and bottom numbers in blood pressure readings are indicators of your health. But just the top number being high might be a concern.

Isometric exercises: Good for strength training?

Learn more about isometric exercises that contract a particular muscle or group of muscles.

Juicing: What are the health benefits?

Learn about the pros and cons of extracting the juice from fresh fruits and vegetables.

Kidney dialysis: When is it time to stop?

Many factors may influence the decision to withdraw from kidney dialysis.

Kidney donation: Are there long-term risks?

Kidney donation can save a life, but it's important to understand the risks.

Kombucha tea: Does it have health benefits?

Does kombucha tea live up to its reputation as a health tonic?

L-arginine: Does it lower blood pressure?

This supplement may help some people lower their blood pressure. Learn who might benefit and who should stay away from it.

Lack of sleep: Can it make you sick?

Lack of sleep can affect your immune system. Here's what you need to know.

Laryngospasm: What causes it?

Laryngospasm is a brief spasm of the vocal cords, which temporarily interrupts breathing.

Late-night eating: OK if you have diabetes?

Late-night snacks aren't necessarily off-limits with diabetes, but healthy choices won't leave you with high blood sugar in the morning.

Latent autoimmune diabetes in adults (LADA): What is it?

Latent autoimmune diabetes in adults (LADA) is a slow-developing form of diabetes.

Leg cramps during pregnancy: Preventable?

A Mayo Clinic specialist shares prevention and treatment tips for leg cramps during pregnancy.

Leg pain after prolonged standing or sitting

New, persistent leg pain or aching may indicate an underlying circulation problem.

Livedo reticularis: When is it a concern?

Learn when this condition that causes a lacy pattern on the skin is simply a result of being chilled or something more serious.

Liver cysts: A cause of stomach pain?

Occasionally, liver cysts can cause pain and discomfort in the upper abdomen.

Loss of sex drive in men: Natural with aging?

Age-related loss of sex drive is normal, but sometimes an underlying condition is at play.

Loss of taste and smell: Natural with aging?

Aging can play a role in the loss of taste and smell — but not always.

Low amniotic fluid: Can it be treated?

Delivery, amnioinfusion and drinking more fluids might be recommended when amniotic fluid is found to be low.

Low blood sodium in older adults: A concern?

For older adults, low blood sodium, known as hyponatremia, can cause death if left untreated.

Low-phosphorus diet: Helpful for kidney disease?

If you have kidney disease, you may need to limit how much phosphorus you eat or drink each day. A dietitian can help you create a custom meal plan.

Lung nodules: Can they be cancerous?

Lung nodules are common. Most aren't cancer. Find out what tests might be recommended if you have a lung nodule.

MAOIs and diet: Is it necessary to restrict tyramine?

A low-tyramine diet is important for anyone taking MAOIs.

MRI: Is gadolinium safe for people with kidney problems?

Older gadolinium contrast agents used with MRI posed a risk for people with severe kidney failure. Newer versions are much safer.

Macrocytosis: What causes it?

Enlarged red blood cells (macrocytosis) can be due to many factors.

Magic mouthwash: Effective for chemotherapy mouth sores?

Find out what ingredients pharmacists combine for this treatment for mouth sores caused by chemotherapy and other cancer treatments.

Male masturbation: Does frequency affect male fertility?

Male masturbation has little effect on sperm count or quality.

Mammogram guidelines: What are they?

Latest Mayo Clinic mammogram guidelines for breast cancer screening.

Marijuana and depression: What's the link?

Marijuana and depression seem to go hand in hand for some people, but there's no clear evidence that marijuana directly causes depression.

Measles vaccine: Can I get the measles if I've already been vaccinated?

Is it possible to get measles from someone else if you've been vaccinated?

Melatonin side effects: What are the risks?

Melatonin is generally safe for short-term use but can cause side effects.

Menopause and high blood pressure: What's the connection?

For many women, menopause and high blood pressure seem to go together. Discover why.

Menopause hormone therapy: Does it cause vaginal bleeding?

Some forms of hormone therapy prescribed to ease hot flashes and other menopause symptoms may cause vaginal bleeding. Learn more.

Migraine medications and antidepressants: A risky mix?

Combining migraine medicines and antidepressants may pose several concerns.

Migraine treatment: Can antidepressants help?

Certain antidepressants are used in migraine treatment. Learn more about these medications.

Migraines and gastrointestinal problems: Is there a link?

Migraines can be associated with certain gastrointestinal problems. Learn more.

Migraines: Are they triggered by weather changes?

Migraines — Are they triggered by weather changes?

Ministroke vs. regular stroke: What's the difference?

The term "ministroke" typically refers to a transient ischemic attack.

Moldy cheese: Is it OK to eat?

Moldy cheese may be unappetizing, but is it unsafe?

Monkeypox: What is it and how can it be prevented?

Find out more about the rare mpox, or monkeypox, viral infection, the possible symptoms in humans, treatment options and how to prevent getting or spreading the virus.

Mononucleosis and Epstein-Barr: What's the connection?

The Epstein-Barr virus sometimes causes a disease known as mono. Learn who is at risk and what the symptoms are.

Mononucleosis: Can it recur?

Mono can return in some rare cases. Learn why that happens.

Monosodium glutamate (MSG): Is it harmful?

Monosodium glutamate (MSG) can trigger headaches and other symptoms in some people.

Mucus in stool: A concern?

Visible mucus in stool can have a variety of causes — not necessarily serious.

Multiple sclerosis: Can it cause seizures?

Seizures occur more often in people with multiple sclerosis than in the general population.

Multivitamins: Do young children need them?

Multivitamins: Are they good insurance for young children?

Myofascial release therapy: Can it relieve back pain?

Myofascial release, a form of manual therapy, may help reduce back pain.

NSAIDs: Do they increase my risk of heart attack and stroke?

Common pain medications such as ibuprofen or naproxen sodium may increase the risk of heart attack and stroke.

Nail ridges: Cause for concern?

Vertical nail ridges are common and often become more prominent with age.

Narrow stools: Should I be concerned?

Narrow stools may be a sign that the colon is narrowing or has a blockage.

Natural breast enhancement: Do supplements work?

Breast enhancement supplements haven't been proved effective and could cause side effects.

Natural remedies for depression: Are they effective?

For some people, certain herbal and dietary supplements seem to help with depression, but more studies are needed on their effectiveness and side effects.

Nausea during pregnancy: A good thing?

Nausea during pregnancy, also called morning sickness, is common. Understand what nausea and vomiting might mean for your pregnancy.

Nervous breakdown: What does it mean?

Nervous breakdown isn't a medical term. It most often means a mental health crisis that affects your ability to meet your own needs and do daily tasks.

Neti pot: Can it clear my nose?

Learn more about this container designed to rinse debris or mucus from the nasal cavity.

Neurontin side effects: How do I manage them?

Some Neurontin side effects can be troubling and require evaluation by your health care provider.

Newborn sleep: Should I wake my baby for feedings?

Get the facts about when to wake a sleeping baby for a feeding.

Niacin overdose: What are the symptoms?

Niacin overdose is unlikely when it's taken as prescribed for high cholesterol.

Nighttime headaches: How can I get relief?

"Alarm clock" (hypnic) headaches wake people up. But other nighttime headaches also can disrupt sleep. Relief begins with determining the cause.

Nocturnal panic attacks: What causes them?

Nighttime panic attacks can cause sweating, rapid heart rate, trembling, shortness of breath, heavy breathing, flushing or chills. Learn about treatment.

Occipital nerve stimulation: Effective migraine treatment?

Occipital nerve stimulation is a relatively new procedure to treat chronic headache disorders.

Ocular migraine: When to seek help

Flashes of light, zigzagging patterns and temporary blindness — what does it all mean?

Omega-6 fatty acids: Can they cause heart disease?

This essential fatty acid is found in certain foods and is recommended as part of a healthy diet.

Opioid stewardship: What is it?

Learn about the roles everyone plays in opioid stewardship, safety and overdose.

Osteopathic medicine: What kind of doctor is a D.O.?

You know what M.D. means, but what does D.O. mean? What's different and what's alike between these two kinds of health care providers?

Outpatient joint replacement: Is it a safe option?

Joint replacement of the hip, knee and shoulder can be done safely as outpatient surgery. Most people can go home the same day as the procedure.

Ovarian cancer: Still possible after hysterectomy?

Surgery to remove your uterus may affect your risk of ovarian cancer, depending on the type of procedure you had.

Ovarian cysts and infertility: A connection?

Certain types of ovarian cysts can contribute to fertility problems.

Ovulation signs: When is conception most likely?

Trying to get pregnant? Learn about ovulation signs and symptoms.

Ozone air purifiers: Can they improve asthma symptoms?

Ozone air purifiers don't reduce asthma symptoms. In fact, they can make asthma worse.

PSA levels: Can they rise after partial prostate removal?

A number of factors can cause PSA levels to rise after surgery for an enlarged prostate.

Pain and depression: Is there a link?

Depression can cause unexplained physical symptoms, such as headaches. Chronic pain can cause problems that lead to depression, such as poor sleep.

Pap smear: Do I need one if I'm a virgin?

Doctors recommend regular cervical cancer screening whether you've had sex or not.

Pap test: Can it detect ovarian cancer?

Unfortunately, there is no standard or routine screening test for ovarian cancer.

Passive-aggressive behavior: What are the red flags?

Learn about the signs of this indirect way of expressing negative feelings.

Penis fracture: Is it possible?

Know the signs and symptoms of a penis fracture.

Petroleum jelly: Safe for a dry nose?

Rarely, inhaling petroleum jelly for prolonged periods can cause lung inflammation (lipoid pneumonia).

Phantosmia: What causes olfactory hallucinations?

Phantosmia is often due to a head injury or upper respiratory infection.

Phentermine for weight loss

This prescription medicine can help with weight loss when combined with a healthy diet and exercise.

Phenylalanine in diet soda: Is it harmful?

You may be worried about phenylalanine because of a warning on diet soda. Find out why the warning is there.

Pink eye: How long is it contagious?

Many parents wonder how long pink eye (conjunctivitis) is contagious. Find out.

Plugged ears: What is the remedy?

Plugged ears are usually a mild, temporary problem. Learn about potential causes and treatments.

Polypill: Does it treat heart disease?

This combination pill contains small doses of several commonly prescribed heart disease medicines.

Poppy seed tea: Beneficial or dangerous?

Poppy seed tea may be used as a natural pain reliever. The key is the opioids in the seed coating, which may be dangerous.

Post-traumatic stress: How can you help your loved one?

Use these tips to help someone cope with stress from a traumatic event, whether it's acute stress disorder (ASD) or post-traumatic stress disorder (PTSD).

Prednisone withdrawal: Why taper down slowly?

Prednisone is a powerful medication. Find out why it's so important to taper off your dosage gradually.

Pregnancy acne: What's the best treatment?

Learn about self-care and safe medications to treat acne during pregnancy.

Pregnancy constipation: Are stool softeners safe?

Pregnancy constipation is common. Know how to safely treat it.

Premenstrual dysphoric disorder: Different from PMS?

Extreme moodiness, intense sadness or marked irritability in the days before your period — along with your usual PMS symptoms — could be PMDD.

Prenatal vitamins: OK for women who aren't pregnant?

Prenatal vitamins: Why they might not be suitable if you're not pregnant.

Probiotics and prebiotics: What you should know

Probiotics are foods or supplements that contain 'good' bacteria that might help treat or prevent illness. Should they be part of your diet?

Prostate cancer metastasis: Where does prostate cancer spread?

Prostate cancer can spread (metastasize) just about anywhere in the body, but it's most likely to spread to the lymph nodes and bones.

Prostate cancer: Does PSA level affect prognosis?

Find out what your PSA level may mean for your prostate cancer prognosis.

Prostatitis: Can sexual activity make it worse?

Some men with prostatitis have pain with ejaculation or sexual activity.

Protein shakes: Good for weight loss?

Protein shakes aren't a magic bullet for weight loss. Here's why.

Pseudoaneurysm: What causes it?

Pseudoaneurysm may be a complication of cardiac catheterization.

Pulse pressure: An indicator of heart health?

Pulse pressure may be a strong predictor of heart problems, especially for older adults.

Reactive hypoglycemia: What can I do?

Reactive hypoglycemia is low blood sugar that happens after eating.

Recurrent prostate infection: What are the treatment options?

These infections that keep coming back can be hard to treat. Here's what to know.

Recurring strep throat: When is tonsillectomy useful?

Tonsillectomy may sometimes be needed in children who have recurring strep throat infections.

Renal diet for vegetarians: What about protein?

Although a renal diet restricts protein, you still must eat some protein every day.

Repeat C-sections: Is there a limit?

Repeat C-sections are common — but each C-section is generally more complicated than the last.

Resperate: Can it help reduce blood pressure?

This device teaches slow, deep breathing, which can reduce blood pressure.

Rhabdomyolysis from statins: What's the risk?

Rhabdomyolysis is a rare but potentially life-threatening side effect of statins.

Rheumatoid arthritis: Can it affect the eyes?

Although rheumatoid arthritis is primarily a joint disease, it occasionally affects the eyes.

Rheumatoid arthritis: Can it affect the lungs?

Although rheumatoid arthritis primarily affects the joints, it can also affect the lungs.

Ricin poisoning

This deadly poison comes from castor bean plants. The same beans are used to make castor oil.

Salt craving: A symptom of Addison's disease?

Constantly craving salt could signal a medical condition, such as Addison's disease.

Scalp psoriasis vs. seborrheic dermatitis: What's the difference?

Learn how to tell apart these common conditions of the scalp, both of which cause inflamed, scaly skin.

Sea salt vs. table salt: What's the difference?

Should you take health claims about sea salt with a grain of salt? What makes it different from table salt?

Secondary infertility: Why does it happen?

Second pregnancies don't always come easily. Learn about possible causes for secondary infertility and when to seek professional help.

Self-care for the flu

How to take care of yourself at home when you have the flu.

Semen allergy: A cause of infertility?

Semen allergy, also called seminal plasma hypersensitivity, is a rare condition that can be easily misdiagnosed. Learn about symptoms and possible treatments.

Sensitive teeth: What treatments are available?

Know what causes sensitive teeth and effective treatments.

Sex and COVID-19: Can you get COVID-19 from sexual activity?

Find out whether COVID-19 can be spread during sexual activity and how to reduce your risk of getting the virus from a sexual partner.

Sex during vaginal infection: Is it harmful?

Vaginal infection makes intercourse painful and weakens your resistance to sexually transmitted infections. Consider waiting.

Shaving hair: Does shaved hair grow back thicker?

Contrary to popular belief, shaving unwanted hair doesn't make it grow back thicker.

Shingles treatment: Does alcohol use affect therapy?

Generally, it's best to avoid alcohol during the course of shingles treatment.

Shingles vaccine: Can I transmit the vaccine virus to others?

A shingles vaccine uses only part of the varicella-zoster virus, so you can't infect others.

Shingles vaccine: Should I get it?

People who are age 50 and older should get this vaccine to prevent shingles.

Should I make changes to my diet if I've been diagnosed with atrial fibrillation?

If you have A-fib, you may need to avoid certain foods or drinks. Know when and why you may need to change your diet.

Silent heart attack: What are the risks?

This type of heart attack occurs with few, if any, symptoms. Find out more.

Silicone breast implants: What happens if they rupture?

Understand the health effects of ruptured silicone breast implants.

Sinus infection and toothache: Any connection?

Sometimes the cause of a toothache isn't a tooth problem, but a sinus problem.

Sitting risks: How harmful is too much sitting?

Sitting for long periods — such as in front of the TV or at a desk — appears to increase risk of death from cardiovascular disease and cancer.

Sleep aids: Could antihistamines help me sleep?

Antihistamines can be somewhat effective as a sleep aid — but only for occasional sleeplessness.

Sleep deprivation: A cause of high blood pressure?

Too little sleep affects not only energy levels but also heart health.

Small cell, large cell cancer: What this means

Cancer cells are classified by how they look under a microscope. Learn common terms used to describe cancer cells.

Soy: Does it reduce cholesterol?

Soy alone doesn't lower cholesterol enough to make a big difference. But eating soy can still be healthy.

Soy: Does it worsen hypothyroidism?

For most people with hypothyroidism, it's okay to have some soy. But the timing makes a difference.

Spastic colon: What does it mean?

This term is sometimes used to refer to irritable bowel syndrome (IBS) — but how accurate is it?

Sperm: How long do they live after ejaculation?

After ejaculation, the life span of sperm depends on the circumstances.

Statins: Do they cause ALS?

Statins can cause muscle injury in some people. But can they also trigger ALS?

Stomach flu: How long am I contagious?

Depending on which virus causes your stomach illness, you can be contagious from a few days to two weeks or more.

Stool color: When to worry

Stool color is usually a result of diet and is only rarely a concern.

Strep throat in young children: A common diagnosis?

Strep throat in young children is uncommon, but it's possible. Learn about symptoms.

Stress and hair loss: Are they related?

Learn how stress and hair loss can be related.

Sulfa allergy: Which medications should I avoid?

Sulfa allergy: A Mayo Clinic expert discusses which medications are likely to cause problems.

Sundowning: Late-day confusion

Sundowning isn't a disease. It's a symptom that often occurs in people with dementia.

Swallowing gum: Is it harmful?

Your body can't digest chewing gum. So what happens when you swallow it?

Tailbone pain: How can I relieve it?

Tailbone pain can have many causes and treatments.

Taurine in energy drinks: What is it?

Energy drink ingredients can cause concern for some who consume these beverages.

Tendinitis pain: Should I apply ice or heat?

Ice is recommended for sudden injuries to tendons. But heat might be a better choice for chronic tendinitis caused by overuse.

Test anxiety: Can it be treated?

Test anxiety can interfere with your performance: Here's what you can do.

Testicular microlithiasis: Is it linked with testicular cancer?

A Mayo Clinic specialist discusses the relationship between testicular microlithiasis and testicular cancer.

Testosterone therapy in women: Does it boost sex drive?

This type of hormonal therapy may boost sex drive for some women, but its long-term safety is unclear.

Tetanus shots: Is it risky to receive 'extra' boosters?

For adults, tetanus shots are recommended every 10 years.

The dawn phenomenon: What can you do?

Take steps to prevent this early-morning increase in blood sugar.

Thin skin? Added protection helps

Fragile or thin skin is a fairly common problem, especially in older adults.

Thyroid disease: Can it affect a person's mood?

Thyroid disease can affect mood, but those symptoms are rarely the only evidence of thyroid disease.

Thyroid guard: Do I need one during a mammogram?

A Mayo Clinic expert discusses using thyroid guards during mammograms to reduce the risk of thyroid cancer from radiation.

Thyroid peroxidase antibody test: What is it?

A thyroid peroxidase antibody test can help determine the cause of thyroid disease.

Tinnitus causes: Could my antidepressant be the culprit?

Ringing in the ears, also known as tinnitus, has many possible causes, such as taking antidepressants.

Toddler speech development: What's typical for a 2-year-old?

A Mayo Clinic specialist describes typical speech development between the ages of 2 and 3.

Too much vitamin C: Is it harmful?

Vitamin C is an essential nutrient, but too much carries its own risks.

Tumor vs. cyst: What's the difference?

A Mayo Clinic expert explains the differences and similarities between these two types of growths and how doctors determine if they're cancerous.

Uncircumcised penis: Is special care needed?

Know how to wash and care for your child's uncircumcised penis.

Underweight? See how to add pounds healthfully

If you're underweight and not happy about it, try these tips to help you achieve your goal weight.

Undigested food in stool: What does it mean?

Undigested food in stool generally isn't a problem unless it's accompanied by other symptoms.

Universal blood donor type: Is there such a thing?

Type O negative is sometimes called the universal blood donor type.

Unusual COVID-19 symptoms: What are they?

Find out about the unusual symptoms of coronavirus disease 2019 (COVID-19), including COVID toes, nausea, and loss of smell or taste.

VLDL cholesterol: Is it harmful?

Like LDL cholesterol, very-low-density lipoprotein (VLDL) cholesterol is considered a type of 'bad' cholesterol.

Vaccines during pregnancy: Are they safe?

Find out which vaccinations you need while pregnant and which ones to stay away from.

Vaginal dryness after menopause: How to treat it?

Low-dose estrogen therapy, vaginal moisturizers and vaginal lubricants are among possible treatments for menopausal vaginal dryness and its discomforts.

Valerian: A safe and effective herbal sleep aid?

Valerian — Can this sleep aid help you sleep better?

Vaping during pregnancy: Is it safe?

Vaping during pregnancy can expose your baby to nicotine.

Vegetarian diet: Can it help me control my diabetes?

Although switching to a vegetarian diet won't cure diabetes, it may offer some benefits.

Viagra for women: Does it exist?

Learn about medicines to treat problems with sexual arousal or sexual desire in women.

Vicks VapoRub: An effective nasal decongestant?

Find out why you should not use this ointment to ease a stuffy nose during a cold.

Vitamin B-12 and depression: Are they related?

Low levels of vitamin B-12 and other B vitamins may be linked to depression, but more research is needed.

Vitamin B-12 injections for weight loss: Do they work?

Vitamin B-12 injections — A weight-loss shot sounds appealing, but does it work?

Vitamin D and MS: Is there any connection?

Some research suggests that vitamin D may reduce the risk of multiple sclerosis (MS).

Vitamin D deficiency

What are the risks of too little vitamin D?

Vitamin D deficiency: Can it cause high blood pressure?

Too little vitamin D is bad for the bones, but what about the heart? Learn how a low vitamin D level may affect blood pressure.

Vitamin D for babies: Are supplements needed?

A Mayo Clinic specialist explains why, when and how to give your baby vitamin D.

Vitamin D toxicity: What if you get too much?

Understand the risks of too much vitamin D, including a toxic reaction.

Vitamins for MS: Do supplements make a difference?

Can vitamin supplements improve MS symptoms?

Vocal cord dysfunction: Is it a type of asthma?

Vocal cord dysfunction and asthma cause similar symptoms, but they're not the same. Find out the difference between the two.

Vulvar varicosities during pregnancy: What can you do?

Vulvar varicosities can cause discomfort during pregnancy. Understand what causes this form of varicose veins and learn how to get relief.

Walking pneumonia: What does it mean?

Walking pneumonia is a mild bacterial infection that resembles a cold. It usually does not require bed rest or a hospital stay.

Walking: Is it enough for weight loss?

Walking and a prudent diet can put you on the path to sustainable weight management.

Warfarin diet: What foods should I avoid?

Certain foods and beverages may interact with warfarin. Find out more.

Warm-mist versus cool-mist humidifier: Which is better for a cold?

Warm-mist and cool-mist humidifiers are equally effective in humidifying the air.

Water after meals: Does it disturb digestion?

Drinking plenty of water helps keep your digestive system on track.

Water retention: Are there natural diuretics?

Interested in natural diuretics for fluid retention and weight gain? You may be better off watching your diet.

What are opioids and why are they dangerous?

Opioids are a broad group of medicines used to relieve pain. Although these medicines are effective, they can lead to addiction. Take them only as directed.

What are superbugs and how can I protect myself from infection?

Some bacteria and other germs are resistant to most types of antibiotics and medicines that treat them. Find out the risks and how to prevent infections.

What is BPA? Should I be worried about it?

Find out more about BPA, a chemical used in some plastics and resins, and explore options for reducing your exposure.

What is a heart failure action plan?

Know when new heart failure symptoms require a call to a health care provider or an ER visit. A heart failure action plan can guide your self-care.

What is chikungunya fever, and should I be worried?

Learn more about this mosquito-borne virus — found in Africa, Asia, India, and parts of Europe and the Americas — that causes fever and severe joint pain.

What is thirdhand smoke, and why is it a concern?

Tobacco smoke creates toxic residue that clings to walls, carpets, clothes and other surfaces.

What's the difference between H1N1 flu and influenza A?

H1N1 flu is a subcategory of influenza A.

When to brush your teeth

When should you brush your teeth? Learn how to protect your oral health.

White coat hypertension: When blood pressure rises in a medical setting

Blood pressure that measures high during a health checkup could be a risk factor for high blood pressure. Find out more.

White patch on skin: A cause for concern?

A small white patch on skin may have several causes, including eczema, psoriasis and vitiligo.

White stool: Should I be concerned?

White stool may mean a serious liver problem. Learn about causes.

Whole-body vibration: An effective workout?

Whole-body vibration — Don't give up regular exercise and a healthy diet.

Why isn't there a hepatitis C vaccine?

Hepatitis C vaccine development is far from straightforward, but experimental vaccines are under study.

Wisdom teeth removal: When is it necessary?

You may not need your wisdom teeth taken out if they're healthy and in the right place. But if they cause problems, your dentist may suggest removing them.

Wrist blood pressure monitors: Are they accurate?

Devices that measure blood pressure at the wrist may be an option for some people. Know how to position a wrist monitor properly.

X-ray during pregnancy: Is it safe?

Learn when an X-ray during pregnancy might cause harm and how to avoid it.

Yeast infection during pregnancy: Over-the-counter treatment OK?

Yeast infections are common during pregnancy. Over-the-counter treatments are usually safe.

Yeast infection in men: How can I tell if I have one?

Yeast infections can occur in men, causing inflammation of the penis (balanitis). Learn what signs and symptoms could mean you have a yeast infection.

Yerba mate: Is it safe to drink?

This herbal tea may help you feel more alert and focused, but find out what the possible health risks are.

Zinc for colds: The final word?

Everyone's heard of taking zinc for colds. But does it really work?