Did you know that, according to the book “Digestive Wellness,” 70 percent of the cells that make up your immune system are located in your digestive system? That’s just one of many good reasons to take care of your GI tract. A good place to start is with probiotics.

A lack of beneficial flora can cause or worsen many health problems:

• Constipation or diarrhea.
• Allergies and asthma. A recent study reported that children who were on antibiotics had more risk of developing these diseases.
• Environmental allergies. In another recent study, people with environmental allergies who took probiotics saw their symptoms improve significantly.
• Acne. A study from Australia reported that acne is due at least in part to a lack of friendly bacteria in the intestine.
• Intestine permeability. Probiotics create a substance called butyrate, which is the fuel for intestinal cells. Anything that harms gut flora also causes intestinal tissue to break down. Intestine permeability is suspected to lead to ulcerative colitis, Crohn’s disease and autoimmune diseases. It also allows alfatoxin (a toxin from black mold on foods or in the environment) to get into your blood stream. This toxin can cause liver damage.

In addition, probiotics also control how you absorb vitamins, minerals, amino acids and even hormones.

A wide variety of prescription and over the counter drugs, including antibiotics, oral contraceptives, acid blockers, corticosteroids, pain medication and chemotherapy, can damage or destroy the good bacteria in your intestine. Unless you actively make the effort to build it back up, it may not recover.

Can you replace good bacteria with yogurt? Not by itself. Yogurt may help a little. But it takes probiotic dosages in the billions daily to keep the intestines colonized. That’s far more than yogurt can supply. In addition, yogurts do not usually contain human strains of probiotics or contain adequate quantities.

If you are going to eat yogurt, makes sure that it has human-strain flora. Eating fermented foods like sauerkraut feeds the good bacteria in the gut. For the best results, find a practitioner to help you select a reliable probiotic supplement and take it daily.

[Ed. Note: Jim LaValle is an educator, clinician and industry consultant in the field of integrative healthcare. He is a licensed pharmacist, board certified clinical nutritionist and doctor of naturopathic medicine with more than 20 years clinical practice experience in the field of natural therapeutics and functional medicine. Named one of the "50 Most Influential Druggists" by American Druggist for his work in natural medicine, LaValle has authored 13 books, including his latest, Cracking the Metabolic Code. For more information, click here.]