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Genes are the building blocks of heredity. They are passed from parent to child. They hold DNA, the instructions for making proteins. Proteins do most of the ...
What is genetic testing? Genetic testing is a type of medical test that looks for changes in your DNA. DNA is short for deoxyribonucleic acid. It contains ...
What are germs? Germs are microorganisms. This means that they can be seen only through a microscope. They can be found everywhere - in the air, soil, and ...
Gluten is a protein found in wheat, rye, and barley. It is found mainly in foods. But it may also be in other products like medicines, vitamins, and supplements. ...
What is gout? Gout is a common type of inflammatory arthritis. It causes pain, swelling, and redness in one or more joints. It usually happens as a flare, ...
Good posture is about more than standing up straight so you can look your best. It is an important part of your long-term health. Making sure that you hold ...
Guillain-Barre syndrome is a rare disorder that causes your immune system to attack your peripheral nervous system (PNS). The PNS nerves connect your brain and ...
What is cholesterol? Cholesterol is a waxy, fat-like substance that's found in all the cells in your body. Your liver makes cholesterol, and it is also ...
What is head and neck cancer? Head and neck cancer is the name for cancers that develop in the mouth, nose and sinuses, salivary glands, and throat and ...
What are head lice? Head lice are tiny insects that live on people's heads. Adult lice are about the size of sesame seeds. The eggs, called nits, are ...
Almost everyone has had a headache. Headache is the most common form of pain. It's a major reason people miss days at work or school or visit the doctor. The ...
What is health literacy? Health literacy involves the information that people need to be able to make good decisions about health. There are two parts: ...
Every pregnancy has some risk of problems, but there are certain conditions and health issues that can raise that risk, such as: A health condition you had ...
What is an inactive lifestyle? Being a couch potato. Not exercising. A sedentary or inactive lifestyle. You have probably heard of all of these phrases, ...
Health statistics are numbers that summarize information related to health. Researchers and experts from government, private, and non-profit agencies and organizations ...
People in the U.S. are living longer, and the number of older adults in the population is growing. As we age, our minds and bodies change. Having a healthy ...
What is sleep? While you are sleeping, you are unconscious, but your brain and body functions are still active. Sleep is a complex biological process ...
A hearing aid is a small electronic device that you wear in or behind your ear. It makes some sounds louder. A hearing aid can help people hear more in ...
Each year almost 800,000 Americans have a heart attack. A heart attack happens when blood flow to the heart suddenly becomes blocked. Without the blood coming ...
What is heart disease? Heart disease is a general term that includes many types of heart problems. It's also called cardiovascular disease, which means ...
