The most reliable way to supplement your diet with Lactobacilli is to make your own yogurt or sauerkraut, or to buy nutritional supplements which have been tested by an independent outside laboratory and which list the concentration of viable bacteria found on culture. Lactobacilli are killed by heat, moisture and sunlight. The making of tablets generates heat which lowers the number of viable organisms. Lactobacilli should be freeze-dried, in powder or capsules, in opaque moisture-proof containers, stored in the refrigerator. They should be consumed with meals. The strains which have been most extensively tested for their viability in the human intestine are L.acidophilus strain NCFM-2 and L.plantarum. L. acidophilus is well-suited to growing in the small intestine, where it is normally one of the dominant bacterial species. L. plantarum has growth characteristics which lead it to grow especially well in the large intestine. The daily dose should be between one billion and ten billion viable bacteria. More may cause gastrointestinal irritation.

Lactobacilli not only colonize the intestinal tract but grow well in the vagina and the urethra, where they prevent growth of pathogenic bacteria. The application of vaginal spermicides like nonoxynol-9, found in many contraceptive creams, may kill Lactobacilli and give pathogens more ready access to the urinary tract. Taking Lactobacilli by mouth or inserting Lactobacillus capsules into the vagina, may restore genital tract symbiosis and prevent infection.