How to Increase the Good Bacteria in Your Intestines

Normal intestinal bacteria are so numerous that they make up approximately 95 percent of the total number of cells in the human body. They help prevent bad bacteria from infecting you, and may help prevent intestinal diseases such as ulcerative colitis, Crohn's disease and cancer.

When you eat, enzymes from your intestines, stomach, liver and pancreas break down your food into its building blocks that can be absorbed into your bloodstream. Carbohydrates are broken down into sugars; proteins into amino acids; and fats into glycerol, fatty acids and monoglycerides. However, many foods contain undigestible starches that cannot be broken down into sugars, so they cannot be absorbed in the upper intestinal tract. When they reach the colon, the "good" bacteria ferment these undigestible starches to form other chemicals including short chain fatty acids that protect your intestinal lining from irritation and cancer, and are absorbed into your bloodstream to lower cholesterol and prevent heart tacks. These same "good" bacteria, such a lactobacillus, are used to ferment and preserve some foods made from milk or plants. So eating yogurt may help you maintain or increase the number of good bacteria you have in your gut. Not all yogurt contains live bacteria; read the label to make sure yours is "active."

The good bacteria break down soluble fiber to form chemicals such as short chain fatty acids that are absorbed into your bloodstream and travel to your liver where they block the liver from making cholesterol and help to prevent heart attacks. These short chain fatty acids also reduce inflammation, so they help to control the diarrhea and ulcers caused by Crohn's disease, and the swelling and pain of arthritis, psoriasis or diabetes. Some studies show they may even improve your immunity to help you to kill germs.

The lactobacilli that are in live cultures of yogurt will not remain in your intestines, so they disappear quickly if you stop eating your daily yogurt. Another way to increase the good bacteria is to eat whole grains, beans, nuts and other seeds, fruits and vegetables. Portions of these foods that cannot be absorbed in your upper intestinal tract, so they pass to your colon and provide the medium for a flourishing colony of good bacteria to grow there. The most likely component of these foods to encourage the growth of good bacteria is soluble fiber. Researchers call these foods "Prebiotics", and the beneficial bacteria are called "Probiotics." Journal references for this article; more on soluble fiber and probiotics.