Ask doctor Cory.

Dear Dr. Cory:

What does gas mean? Does it mean that you are healthy? Does it have anything to do with what you are doing? I get gas when I am stretching, and my cousin gets gas after he swims.

Tannisse

Selma, California

Dear Tannisse:

Passing gas is part of our normal digestive process, so, yes, it is healthy. On an average day, most people produce between a pint and a half-gallon of gas. Some of it is odorless. Some is not.

Certain activities cause a person to swallow air and can cause gas. Children who chew gum and children with allergies swallow more air than others. Sometimes the swallowed air comes out as a burp, and sometimes it comes out the other end!

When your cousin swims, he may be swallowing more air than usual. And when you stretch, air travels through your digestive system and escapes as you move.

Drinking carbonate soft drinks adds gas to the stomach. What we eat makes a difference, too. Beans, broccoli, Brussels sprouts, cabbage, fruits, and sweetened drinks contain sugars the body can't use. As a result, it passes them along as gas.

Bacteria that live in our large intestine to help us digest tough parts of foods like bean skins make gas as a waste product.

Being in good shape may help you have less gas! Our intestines absorb most of the gas we make. If the muscles that support our intestines (our abdominal muscles) are in good shape, then the intestines will work better at absorbing gas.

As you have found, exercise also helps move the gas along. So if you are feeling gassy, do something active like walking or stretching!

Dear Dr. Cory:

I have three rabbits and I know they can get mastitis when they are pregnant, but what about humans? Can they get it? How and why?

Jenny

Poulsbo, Washington

Dear Jenny:

Mastitis (mas-TIE-tis) is an infection of the breast or mammary gland. It usually occurs in mother rabbits that are nursing their young. The same is true for humans.

Mastitis can occur in about a third of breastfeeding women. Bacteria or sometimes a fungus can enter the breast through a nipple where the skin has be come broken or cracked due to nursing. To help prevent mastitis, nursing mothers should be sure to:

* Wash their hands before a feeding;

* Position their baby correctly;

* Feed their baby frequently;

* Get plenty of rest and fluids. Breast infections usually need to be treated with an antibiotic that is safe for the baby.

Sincerely, Cory SerVaas, M.D.