Acidophilus Effects, Benefits and Other Information

What are probiotics?

The digestive tract maintains a balance between healthy and potentially harmful micro-organisms. Healthy micro-organisms, also called microflora, are residents of the digestive tract that have a protective role in our bodies.

When we grow older, use prescription drugs such as antibiotics and corticosteroids, eat meat, travel, and have digestive disorders, the proportion of healthy microflora in our bodies declines and is less able to protect us from disease.

In addition to its protective role, microflora helps to synthesize important vitamins, nutrients and enzymes, such as the lactase needed to digest lactose in milk and dairy products.

It also allows for the removal of heavy metals and other harmful ingested substances in our food, such as from the metal lining of drink boxes and canned foods.

Besides the digestive tract, microflora reside in other areas where mucous membranes are exposed to the environment, such as the skin, respiratory tract and genital-urinary tract.

To put it into perspective, there are approximately 100,000 billion viable bacteria in the digestive tract and about 1,000 billion on the skin. The total number of cells in the body is approximately 10,000 billion, meaning that we have more bacteria in our body than we have cells! In the large intestine, there are at least 400-500 species of bacteria1.

Probiotics, the supplement form of micro-organisms, have been used for many years to increase the proportion of protective microflora and to prevent and treat many health conditions. The most familiar form of probiotics is yogurt.

Two strains of healthy bacteria, Lactobacilli and Bifidobacteria, are found in yogurt, cheese, and other fermented foods. Daily intake of foods containing these bacteria have been suggested to provide health benefits including improved digestion and alleviation of constipation, increased absorption of dietary minerals, reduced blood cholesterol levels and enhanced protection from tumors.

Many strains of bacteria have been used in probiotic supplements. The most common strains are Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum, Bifidobacterium longum and the yeast Saccharomyces boulardii. Of the beneficial strains, the Lactobacillus species is most prominent in the small intestine, whereas Bifidobacteria tends to reside in the large intestine.

Vegetarians tend to have a healthier balance of “good bacteria” to “bad bacteria” as compared to non-vegetarians who tend to have larger numbers of undesirable bacteria such as Bacteroides.

How do probiotic supplements work in the digestive system?

Beneficial strains such as Lactobacillus species and Bifiobacteria species prevent the harmful strains such as E.coli and Bacteroides from growing to a population where they can cause disease. They do this by producing organic acid and hydrogen peroxide, by spatial exclusion, which means they crowd out other bacteria, by substrate competition, when they compete with harmful bacteria for nutrients needed for growth, and by bacteriocin production, which is the production of compounds that have a lethal effect on harmful bacteria.

Therapeutic Uses

Probiotics can be used in situations where the intestinal microflora balance has been disturbed and related digestive tract dysfunction occurs. Besides improving digestion and preventing gas, bloating, and bad breath, probiotics are beneficial in many other situations:

What to look for in a probiotic supplement

The most common strains of probiotics are Lactobacillus acidophilus for the small intestine and Bifidobacterium bifidum for the large intestine.

Probiotics should always be refrigerated before and after opening. Storage temperature should be below 3-4 degrees C.

FOS (fructo-oligosaccharides) is often added to promote the growth of selected strains of bacteria. Synthesized naturally from sucrose, it is not digested by the small intestine but is fermented in the colon. A linear relationship has been found between the amount of FOS consumed and the count of bifidobacteria in the intestine. The optimal and well-tolerated dose of FOS has been found to be 2000-3000mg per day 11. While excess FOS could cause excess gas, abdominal cramps, and bloating2, many probiotics have only small amounts of FOS in the range of 200mg.

Each capsule or dose should contain more than 1 billion viable bacteria. The minimum therapeutic dose is suggested to be 108-109 cells per day. More bacteria per capsule or dose is preferable, since the bacteria must survive during shelf life and then after ingestion, during transit through the acidic conditions of the stomach and hydrolytic enzymes and bile salts in the small intestine.

Bifidobacteria is anaerobic, meaning that it lives and grows in the absence of oxygen. One study found that bifidobacteria could survive and multiply better in glass bottles than plastic containers, probably because oxygen cannot permeate glass bottles easily. For this reason, also look for opaque containers.

Look for products that have vitamin C (ascorbic acid), whey protein, or cysteine added. Vitamin C acts as an oxygen-scavenging agent and can improve the survival and multiplication of bacteria such as Lactobacillus. Studies have found that whey protein and the amino acid cysteine also improve the viability of bacteria.

When selecting a probiotic, it is necessary to consider the intended use of the probiotic, its source, its site of isolation and characteristics of the strain. It is wise to consult a health care provider such as a qualified nutritionist or a naturopathic doctor who can evaluate the options and recommend the most appropriate probiotic supplement.

References

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