Probiotic intestinal bacteria


Your first line of defense?
When we speak of preventing and stopping disease, the immune system first comes to mind. The skin acts as a barrier to unwanted pathogens (bacteria, viruses, and fungi that cause health problems), and if they breech this first wall, the immune system attacks. What many of us don't know is that the immune system is not always our first defense. Instead, bacteria yes, bacteria are.
The home guard in the digestive tract are what we call "friendly" bacteria. These are bacteria that fight off the bad bacteria such as E. coli and keep our intestinal tracts "in balance." When friendly bacteria are not at appropriate levels, and when unfriendly bacteria dominate, health problems can result. These include gas, bloating, intestinal toxicity, constipation, and malabsorption of nutrients.
These friendly bacteria which are often known as probiotics when in supplement form have a number of health benefits.
Antibiotic effects
We all know what antibiotic activity is: the ability to hunt down and kill harmful bacteria. We also realize that pharmaceutical antibiotics do have a downside they kill all our bacteria, including our good bacteria, and have side effects. And, of course, the increasingly common problem of antibiotic-resistant bacteria bacteria that cannot be killed by our arsenal of antibiotics is due to our overuse and overdependence on antibiotics.
Many types of friendly bacteria produce their own antibiotics, although "replacement-biotics" might be a better word. That is because friendly bacteria produce substances that inhibit or "scare" the bad bacteria, preventing them from forming colonies that eventually cause problems. Natural antibiotics produced by friendly bacteria do not have any uncomfortable side effects.
Antiviral effects
Viruses are another pathogen of which we are all aware. The common cold is a viral infection, as is human immunodeficiency virus (HIV). However, viruses are much harder to treat and destroy than bacteria. To date, there is no class of drugs known to destroy viruses completely, although there are antiviral agents that prevent against the virus initially doing damage.
Some friendly bacteria have antiviral effects they help prevent a viral foothold from becoming a serious threat. Although the exact mechanism by which these bacteria do this is not known, there have been a number of laboratory tests that indicate that certain strains produce hydrogen peroxide, which functions as a virus killer. In her book Probiotics, Nature's Internal Healers, Natasha Trenev documents several studies in which friendly bacteria were used to inhibit the herpesvirus.
Anticancer effects
By now, most of us realize that diet can be a risk factor for cancer a diet high in animal fat and fried foods may contribute to a number of types of cancer. One of the reasons for this may be because cancer-causing substances are produced in the body from the nitrates used in the curing of luncheon meats. Friendly bacteria have the ability to neutralize nitrates.
In 1987, Fernandes, et al., (FEMS Microbiology Reviews 46) listed ways that friendly bacteria may destroy cancer:
- 1) Some species of friendly bacteria eliminate potentially cancer-causing substances before they "turn" cancer-causing.
- 2) Some strains have the ability to alter enzymes that turn a potentially carcinogenic agent into a carcinogenic agent.
- 3) Some strains have the ability to suppress some tumor activity.
"Postulated health advantages associated with probiotic intake" 1) Alleviation of symptoms of lactose malabsorption The American Journal of Clinical Nutrition, May |
Other benefits
In addition to these three benefits, friendly bacteria also have the ability to
- manufacture vitamins B1, B2, B3, B5, B6, B12, A, and K, and essential fatty acids;
- aid in the digestive process by helping digest lactose (milk sugar) and protein;
- clean the intestinal tract, purify the colon, and promote regular bowel movements;
- increase the number of immune system cells;
- create lactic acid, which balances intestinal pH;
- protect us from environmental toxins such as pesticides and pollutants, reduce toxic waste at the cellular level, and stimulate the repair mechanism of cells;
- help maintain healthy cholesterol and triglyceride levels; and
- break down and rebuild hormones.
Lactobacilli are one of the most important types of friendly bacteria found in the digestive tract. These bacteria get their name (lacto) because they are able to turn milk sugar into lactic acid. They play a key role in producing fermented milk, yogurt, and cheeses.
The "father" of lactobacilli could well be Elie Metchnikoff, who, in 1908, noted that people in Bulgaria lived longer than those in other countries, despite the fact that Bulgaria was considered "underdeveloped." His investigation of this led him to diet, yogurt, and lactobacilli. His work was the first to prove that lactobacilli could transform milk sugar into lactic acid. Metchnikoff also hypothesized that this acidity would provide a hostile environment for unfriendly bacteria. This was later proved correct.
Lactobacilli are able to "balance" unfriendly bacteria because when they produce lactic acid, they alter the intestinal environment, making it unsuitable for unfriendly bacteria. In other words, lactobacilli don't destroy the unfriendly bacteria; they destroy their home, forcing them to leave.
Lactobacilli have other benefits. They may help normalize cholesterol levels, and certain strains may antagonize Candida albicans. There is indirect evidence that lactobacilli may help relieve anxiety and depression. This is because the amino acid tryptophan serves as an antidepressant, and lactobacilli release this amino acid.
Bifidobacteria
Bifidobacteria are friendly bacteria, colonizing mainly the large intestine, or colon. Bifidobacteria
are considered extremely important to the health of the gastrointestinal tract. The bifidobacteria
have been used to address intestinal disorders, and boost the immune system. These strains
are also important for the production of B vitamins.
Bifidobacteria may also reduce antibiotic-induced fluctuations in intestinal bacteriavii and
the GI distress that can ensue.viii Antibiotics are particularly effective at killing all kinds
of bacteria, good and bad-often leading to secondary infections.
Bifidobacterium bifidum is especially good at enhancing the body's immune response and inhibiting
harmful enzymes.ix Bifidobacterium longum has a high affinity for intestinal colonizationx,
improving the intestinal environment, which leads to better regularity.
Food for the friendly bacteria
Bacteria need nourishment. They get this from our diet, especially fiber. However, there are "special" foods which friendly bacteria find particularly tasty.
One of these is fructooligosaccharides, or FOS. FOS are sugars linked together in such a way that they cannot be digested. Instead, FOS pass through the stomach to the small intestine and colon where they are consumed by our friendly bacteria.
Feeding friendly bacteria is not all that FOS do for us. FOS can also
- reduce the growth of unfriendly bacteria,
- maintain regular bowel movements,
- maintain cholesterol and triglyceride levels, and
- maintain healthy blood sugar levels.
FOS should not be seen as a replacement for friendly bacteria. They are meant to amplify the benefits of friendly bacteria, not replace them.
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