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What Is H. pylori?

Helicobacter pylori (H. pylori) is a type of bacteria. These germs can enter your body and live in your digestive tract. After many years, they can cause sores, called ulcers, in the lining of your stomach or the upper part of your small intestine. For some people, an infection can lead to stomach cancer.

Infection with H. pylori is common. About two-thirds of the world’s population has it in their bodies. For most people, it doesn’t cause ulcers or any other symptoms. If you do have problems, there are medicines that can kill the germs and help sores heal.

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If your doctor just broke the news that you're lactose intolerant, it doesn't mean you'll never get to savor another bite of ice cream. At first, many people fear they'll have to give up all dairy products, says Dee Sandquist, RD, a dietitian in Fairfield, Iowa. But with some trial and error, most people find they can still eat small amounts of dairy without having symptoms such as bloating, gas, stomach pain, diarrhea, or nausea. Dairy foods are important to the health of your bones, because they're...

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As more of the world gets access to clean water and sanitation, fewer people than before are getting the bacteria. With good health habits, you can protect yourself and your children from H. pylori.

How H. pylori Makes You Sick

For decades, doctors thought people got ulcers from stress, spicy foods, smoking, or other lifestyle habits. But when scientists discovered H. pylori in 1982, they found that the germs were the cause of most stomach ulcers.

After H. pylori enters your body, it attacks the lining of your stomach, which usually protects you from the acid your body uses to digest food. Once the bacteria have done enough damage, acid can get through the lining, which leads to ulcers. These may bleed, cause infections, or keep food from moving through your digestive tract.

You can get H. pylori from food, water, or utensils. It’s more common in countries or communities that lack clean water or good sewage systems. You can also pick up the bacteria through contact with the saliva or other body fluids of infected people.

Many people get H. pylori during childhood, but adults can get it, too. The germs live in the body for years before symptoms start, but most people who have it will never get ulcers. Doctors aren’t sure why only some people get ulcers after an infection.


If you have an ulcer, you may feel a dull or burning pain in your belly. It may come and go, but you’ll probably feel it most when your stomach is empty, such as between meals or in the middle of the night. It can last for a few minutes or for hours. You may feel better after you eat, drink milk, or take an antacid.

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