The small intestine is approximately 20 feet long and is lined with millions of tiny villi, which are like fingers or projections with the primary responsibility for the absorption of nutrients. If you were to flatten out the villi and the small intestinal wall, it would stretch as wide as a tennis court.

This enormous surface area is devoted to assimilation. Digested food, or “chyme,” and fiber make up about 60 percent of the mass that travels through the intestinal tract. The rest of the volume is made up of mucus and bacteria. Which kind of bacteria there is has everything to do with your health.

Bad Bacteria

While most people have heard of peptic ulcers, they may not have heard of the organism behind it. The disease-causing bacterium Helicobacter pylori is actually the culprit. Ulcers aren’t the only problem with bacteria. Researchers are beginning to link obesity and nonalcoholic liver disease with other types of intestinal bacteria.

If you don’t have enough friendly bacteria, it means your intestinal microflora is out of balance. So what? Without enough friendly bacteria, your overall health is affected. How else can you combat the bad, or pathogenic, bacteria like salmonella, klebsiella, clostridia, giardia (waterborne parasite), shigella (dysentery), or staphylococcus (infection)? Whenever healthy bacteria are diminished, bodies become threatened by opportunistic bacteria, other parasites, fungi, and candida (yeast). Modern food processing leaves very few of the good-guy bacteria behind.

Good Bacteria

Probiotics decrease inflammation in the gut, can help provide nutrition needed for healthy gut lining cells to synthesize vitamins such as the B vitamins biotin and folate, and can break down certain cancer-causing chemicals (carcinogens) in our diet. Probiotics decrease responses to both food allergens and pollen allergens.

Another advantage of probiotics is that they are believed to produce antibacterial substances, which render harmless or kill hostile bacteria. The probiotics are able to do so by changing the area’s levels of acidity. In doing so, it deprives the disease-causing bacteria of their nutrients.

Probiotics produce natural antibiotics (acidophilus produces the antibiotic acidophilin) and can reduce or prevent infections in the gut. Probiotics are commonly prescribed now to prevent or treat Clostridium difficile bacterial infection, a common complication of antibiotic therapy.

Produce More Vitamins

Good bacteria manufacture some of the B vitamins, including niacin (B3), pyridoxine (B6), folic acid, and biotin. Plus, they manufacture the milkdigesting enzyme lactase which helps digest dairy products.

Protect Against Cancer

Many researchers believe that interactions between diet, the intestinal microflora, and the cells in the lining of the colon, together with genetic factors, may be what causes colon cancer to develop. Healthy bacteria may help maintain a healthy intestinal microflora and promote a healthy environment. Another theory for the cause of colon cancer is that prolonged exposure to cancer-causing compounds in the colon may trigger the process.

Protect Your Intestines

When intestinal function is altered, it may increase the risk for developing certain chronic intestinal disorders such as colon cancer, Crohn’s disease, ulcerative colitis, irritable bowel syndrome, and diarrhea. Probiotics have been shown to have a detoxifying effect in the colon. Prevention of diarrhea is the most frequently touted health claim for probiotics.