Commonly known as “friendly flora” or “probiotics”, Lactobacillus acidophilus and bifidus species are microorganisms that live in the human intestinal tract. These “good” bacteria assist with digestion of food and produce natural antibiotic substances. They also play a role in normal immune function, cholesterol metabolism, digestion and absorption, and cancer prevention. Interestingly, when adequate fiber is present in the intestines, these bacteria synthesize short chain fatty acids such as butyrate, etc. that inhibit the key enzyme (HMG CoA Reductase) involved in the liver’s synthesis of cholesterol. This is the mechanism by which they help to modify blood cholesterol levels. Normally these bacteria coexist in balance with other organisms such as E. coli and yeast. However, antibiotic drugs may kill some of the good bacteria along with the harmful ones, resulting in an imbalance in the bacterial species in the intestines. This, in turn, can lead to overgrowth of one or more types of disease-causing organisms. This process is known as intestinal dysbiosis.
In any form of supplementation, in order to be effective, the bacteria must be alive, so it is important to find good quality sources. “Acidophilus” means “acid-loving”, indicating that these bacteria thrive in acidic conditions and require a food source to survive such as lactose or fructooligosaccharides (FOS). Acidophilus may be found in food sources such as fresh, unpasteurized yogurt (pasteurization kills all bacteria) or in acidophilus milk. Check the label to make sure the yogurt or milk was cultured with acidophilus after pasteurization. Acidophilus and bifidus are also available in capsule or powder forms.
Quality products will be refrigerated at the store and should be kept refrigerated at home as well. Good packaging of these products also utilizes dark glass or plastic bottles and is dated. The label should also indicate the number of total organisms present (which should be >3 billion acidophilus organisms per cfu or colony-forming unit, plus >1 billion bifidus organisms per cfu). Some brands are more reliable than others in regards to content of specific bacterial species. This point is especially important for immune compromised individuals.
Acidophilus and bifidus supplementation is used to restore a normal, healthy population of intestinal organisms in various situations or conditions including intestinal dysbiosis following antibiotic treatment or following various intestinal infections/infestations, vaginitis and urinary tract infections. Supplementation may be taken by mouth or in the form of a douche or vaginal suppository depending on the specific condition. Sometimes a combination of treatments is used.
Acidophilus and bifidus are killed by alcohol and antibiotics. Avoid alcohol while taking these probiotics in any form for therapeutic purposes. If you are taking antibiotics, wait until you have finished the course of treatment before starting acidophilus/bifidus. Although fresh yogurt containing live microorganisms may be more digestible than pasteurized yogurt, opt for capsules if you have an allergy or intolerance to milk products.
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