Bacteria are often maligned as the cause of human and animal disease, yet “friendly bacteria” or health-promoting bacteria far outnumber the pathogenic variety in the body.
“Friendly bacteria help to maintain the system of checks and balances and can inhibit the growth of harmful, disease-causing bacteria,” said Roger Clemens, director of the Laboratory for Analytical Research and Services in Complementary Therapeutics at the USC School of Pharmacy. “They are especially prevalent in the gastrointestinal or GI tract and may assist in the digestion of food and the absorption of essential vitamins. More importantly, these friendly bacteria may modulate our body’s immune system in order to ward off potential infections.”
Probiotics, which are live organisms that contribute to intestinal microbial balance through ingestion, have become increasingly popular in traditional dairy foods and in the health food industry. This is due to research that suggests a positive correlation between health maintenance and a decrease of friendly bacteria in the body preceding or during various disease episodes.
On November 26, Clemens discussed these issues in his lecture entitled “Friendly Bacteria.” The lecture was sponsored by the School of Pharmacy and was attended by about 50 staff and faculty members.
The microflora profile (type of bacteria) in the GI tract is determined shortly after birth at the time of the first feeding and throughout the first week of life. In utero the GI tract is sterile.
“From infancy, every person develops a unique microflora profile that remains relatively constant throughout their lifetime,” said Clemens. “Studies show that a breast-fed child has a different microflora profile than a formula-fed child, which may contribute to less disease and less allergies in the breast-fed child.”
According to Clemens, microflora in a breast-fed infant is rapidly transmitted from its mother and immediate environment during normal delivery and throughout lactation, increasing resistance to certain childhood diseases like ear infections and diarrhea. Research among newborns also suggests that an early introduction of probiotics, even during the last trimester of pregnancy, may deliver health benefits to the child through the early GI colonization of friendly bacteria.
Common illnesses observed in adults such as GI disturbances, Crohn’s disease, bacterial vaginosis and even constipation may be associated with an imbalance of specific bacterial strains in the body. According to research, ingesting selected strains of bacteria may decrease the duration and severity of these illnesses just as well as traditional pharmacological interventions.
These practices are commonplace in Japan, Sweden, Finland and in parts of Europe — and are gaining credibility and notoriety throughout the United States, as well as with the FDA and the World Health Organization.
Scientists and dietitians alike are looking to discover new ways to incorporate friendly bacteria (such as lactobacilli and bifidobacteria) into adult diets, either through dietary supplements or natural food sources.
“Many fermented foods such as yogurt, kefirs (fermented milk) and other products containing live and active cultures may be helpful in increasing levels of friendly bacteria in the GI tract,” said Clemens. “It takes 7-10 days for it to make a noticeable difference and will only work in adults for as long as they are incorporating these foods in their diet.”
In dietary supplements, probiotics are not regulated by federal or state statutes and may not always contain the declared level of the bacteria strain. Usually, live organisms require refrigeration to maintain their viability, yet many retailers do not adhere to directions appearing right on the label, said Clemens.
Yogurt is the perfect food as a vehicle of delivering friendly bacteria and providing good nutrition. Typical yogurt contains live and active cultures of Lactobacillus bulgaricus and Streptococus thermophilus, as required by federal guidelines. Yogurt also contains calcium and protein that helps protect against osteoporosis and maintain muscle.
“Eating a yogurt every day could be extremely beneficial,” said Clemens. “Look for a brand that has the official seal of the National Yogurt Association, which guarantees that the product contains live and active cultures at guaranteed levels.”