Friendly bacteria can boost your immune system—and help avert a case of traveler’s diarrhea

Whether from supplements or food sources, probiotics help reestablish healthy intestinal flora. This is critical anytime these friendly bacteria are flushed out by diarrhea or decimated by antibiotics. Probiotic bacteria also help control the overgrowth of vaginal yeast (candida) that triggers yeast infections in women. Furthermore, they aid digestion, stimulate immune function, and help prevent diarrhea. Probiotics may also help prevent colon cancer, allergies, dermatitis, and post-surgery infection, as well as treat inflammatory bowel disease (Clinical Reviews in Allergy & Immunology, 2002, vol. 22, no. 3) and Crohn’s disease (Annals of Nutrition and Metabolism, 1996, vol. 40, no. 3).

How they work
In the intestines, bacteria compete for real estate where they can establish colonies. When the intestine hosts large colonies of beneficial bacteria, a stray harmful germ (such as E. coli) cannot multiply to dangerous numbers simply because it can’t find any unoccupied space on the intestinal wall to call home.

Probiotics produce organic compounds (including lactic acid, hydrogen peroxide, and acetic acid) that increase intestinal acidity; this inhibits the reproduction of many harmful bacteria. Probiotics also produce substances called bacteriocins that act as natural antibiotics to kill undesirable micro-organisms. In addition, probiotics enhance immune function by boosting disease-fighting cells (Journal of Nutrition, 2000, vol. 130, no. 2 Suppl).

Traveler’s diarrhea afflicts as many as half of tourists traveling to exotic locales. Studies show that taking probiotic supplements throughout a trip can reduce the risk of being waylaid by “Montezuma’s revenge” (American Journal of Clinical Nutrition, 2001, vol. 73, no. 2 Suppl). In one study of American tourists, taking supplement L. rhamnosus GG throughout their trip cut the chance of getting diarrhea in half (Journal of Travel Medicine, 1997, vol. 4, no. 1).

Anytime your doctor prescribes antibiotics, there’s a good chance you’ll end up with digestive upsets and/or a case of the runs. Antibiotics indiscriminately kill off bacteria both the bad ones causing your condition and the good ones that live in your intestines and (if you’re a woman) in your vagina. As good bacteria die off, harmful ones have a better chance of thriving and causing diarrhea.

Diarrhea is particularly troublesome in infants and young children because their small bodies become dehydrated more quickly. Studies show that the Lactobacillus GG strain, in particular, helps end diarrhea episodes in children (Journal of Pediatric Gastroenterology and Nutrition, 2000, vol. 30, no. 1).

Yeast infections which can be triggered by antibiotic use as well as hormone changes and pregnancy also can be prevented and treated by probiotics. Studies show benefits from taking probiotic supplements, eating live-culture yogurt, and even applying yogurt directly in the vagina (Journal of the American Medical Association, 1996, vol. 275, no. 11).

Probiotics shorten the common cold in study

To strengthen your immune system, add a daily dose of probiotics.  Researchers concluded from a recent study at the Institute for Physiology and Biochemistry of Nutrition in Germany that participants who took supplemental probiotics daily for at least three months shortened bouts of the common cold by almost two days and reduced the severity of symptoms such as headaches, coughing, and sneezing (Clinical Nutrition, 2005, vol. 24, no. 4).

“Probiotics are not just good for the gut, they are also a good immune stimulator,” says Hilary Andrews, ND, an adjunct professor at the National College of Naturopathic Medicine in Portland, Oregon. “The bacteria in probiotics strengthen the immune system by providing it with extra stimulation, and then when we are exposed to viruses or harmful bacteria, the immune system is strong enough to handle them quickly and effectively.”

Be careful when choosing a brand because not all probiotics are created equal. Use only SCD approved probiotics or, better, yet . . . make the 24-hr. SCD yogurt that is very high in probiotics and lactose free . . . and delicious.


See * MAKING YOGURT & OTHER FERMENTED FOODS for SCD approved choices of probiotics.