(2) Avoid Unnecessary Antibiotics. The second line of defense against intestinal infection is the normal intestinal bacteria, especially Lactobacilli residing in the small intestine. Antibiotics decimate Lactobacilli. In so doing, they increase the risk of subsequent intestinal infection. Strategies for avoiding or reducing antibiotic use are also described in The Four Pillars of Healing and will form the basis for a future column.

(3) Supplement your diet with friendly bacteria, especially if you must take antibiotics. A large body of research over the past ninety years has demonstrated the preventive value of eating foods fermented with Lactobacilli (like the well known Lactobacillus acidophilus) or their cousins, the Bifidobacteria. Eating these friendly bacteria helps to prevent antibiotic-induced diarrhea and travelers diarrhea. The daily dose should be between one billion and ten billion viable bacteria. More may cause gastrointestinal irritation. Lactobacillus plantarum, a species of bacteria that grows on plants, is the only Lactobacillus not harmed by antibiotics and can be taken simultaneously with them. Lactobacillus plantarum grows naturally in fermented vegetables like sauerkraut and is also available in pill form.

(4) Eat a diet high in fiber. Fiber is the term that describes remnants of plant cells that are resistant to human digestion. The usual sources are vegetables (especially beans, peas and winter squash), whole grain cereals and breads (made from whole wheat, brown rice or whole oats), nuts, and seeds. Among fruits, one gets the most fiber per serving from apples and berries. High fiber diets support the growth of Lactobacilli and other friendly flora in the large intestine and inhibit the ability of disease causing bacteria and parasites to attach themselves to the intestinal wall.

Carrots, carob, blueberries and raspberries contain complex sugars (oligosaccharides) which interfere with the binding of pathogenic bacteria to the intestinal lining. Juices made from these plants have been used in Europe for centuries for the treatment or prevention of diarrhea.

(5) Use antimicrobial herbs and spices. Before they were used as seasoning, culinary herbs and spices were most likely used for food preservation. Antimicrobial activity of garlic has been repeatedly demonstrated against many species of bacteria, fungi, parasites and viruses. The dose of garlic needed to obtain significant benefit is at least ten grams (about three small cloves) per day. Onion lacks the potency of garlic but can be consumed in much larger quantity, so that its antimicrobial benefits may be equal to those of garlic if consumed regularly. Turmeric relieves intestinal gas by lowering the numbers of gas forming bacteria; it also has anti-fungal activity and has been traditionally used for relieving inflammation. The effective dose is about one gram per day. Ginger, which contains over four hundred chemically active ingredients, has long been used for the treatment of digestive complaints. It protects the intestinal lining against ulceration and has a wide range of actions against intestinal parasites. Sage and rosemary contain the essential oil, eucalyptol, which kills Candida albicans, bacteria, and worms. Oregano contains over thirty biologically active ingredients of which twelve have antibiotic, antiviral, antiparasitic or antifungal effects. Heating at 200 degrees (Fahrenheit) for twenty minutes destroys the antibacterial activity of most of these spices. They should be added to food at the end of cooking, just before being eaten.