Probiotics - Bacteria that are Good for Your Health
~ February 1997 No.2 ~
Microbiologists have studied the large number of bacteria in the intestine of humans for some time. Their first task was to count and identify the many different bacteria. This has proven to be such a big job that it is still going on. As various bacteria were identified, people started asking what these bacteria were doing in the intestine. It soon became evident that the bacteria residing in the intestines could be affected by their host and vice versa. Quickly the findings of the microbiologists started to interest others concerned about nutrition, metabolism, health.
It was British scientist, Roy Fuller who first popularized the definition of a probiotic. Fuller credits another scientists D. Lilly and R. Stillwell for actually coining the word. According to Fuller a probiotic is ‘a live microbial feed supplement which beneficially affects the host animal by improving its intestinal microbial balance’.
Fuller’s definition applied to his work with animals, but it was quickly modified and extended to include humans. The number of foods that are considered to be probiotics is not large but probiotic foods are probably more familiar to the consumer in terms of being good for your health. yogurt, kefir, and koumis are fermented milk products that have long histories. All three are considered probiotics. There are other, less well known, probiotics on the market now. Food manufacturers are researching other products that contain bacteria that could soon be on the market as probiotics.
An even faster growing trend is the sale of foods that are prebiotics. Prebiotics are foods that contain nutrients that are required by bacteria for growth and metabolism. The bacteria that live in the intestines of humans survive on the supply of partially digested food that is passing down the gastrointestinal tract. Certain bacteria require specific nutrients to grow. If the diet of the human contains those nutrients the bacteria will survive and grow; if the nutrients are not in the diet, the bacteria cannot grow. Adding or increasing specific foods or food ingredients to the diet, changes the numbers and types of bacteria in the intestines.
The largest group of prebiotics on the market right now are oligosaccharides. These complex sugars are required by certain intestinal bacteria. By including oligosaccharides in the diet, the growth of specific bacteria populations can be altered.
National Center for Complementary and Intergrative Health Oral
Probiotics: In Depth