Lactobacillus acidophilus, commonly referred to simply as acidophilus, is a friendly inhabitant of the gastrointestinal (GI) tract. It, as well as some related strains of bacteria, is known as a probiotic. Probiotic organisms secrete enzymes that support healthy digestion. They keep the flora of the intestines and vagina balanced, and compete with some pathogenic organisms. When the probiotic population of the body is severely decreased, as can occur with treatment by many antibiotics, yeasts and harmful bacteria may take over and cause illness. Normal and healthy amounts of acidophilus can also be decreased by chronic diarrhea, stress, infections, and poor diet.
The species of Lactobacilli that inhabit the GI tract cause an increase of acidity. The bacteria do this by producing lactic acid from milk sugar (lactose). The increased acidity may promote the absorption of calcium, as well as of some other minerals. Lowered pH also discourages the growth of many pathogenic species of bacteria and yeasts. The hydrogen peroxide produced by the acidophilus also helps to suppress pathogens.
Acidophilus may be used to reduce susceptibility to vaginal yeast infections, which are quite common. Symptoms including itching, burning, inflammation, and discharge occur due to an overgrowth of the yeast Candida albicans, which is part of the normal vaginal flora. Some women are more prone to yeast infections than others. Antibiotics destroy the normal probiotic flora, and may lead to yeast infections. High sugar levels are another predisposing factor. Diabetics, who tend to have high blood sugar, and persons who consume a processed diet that is high in sugar have more frequent problems with yeast as well. The hormonal states created by pregnancy or the use of oral contraceptives also contribute to yeast infections. IUD users can also have an increased rate of infection. In rare cases, Candida is sexually transmitted, and both partners may require treatment in order to control repeated overgrowth. Anyone who has AIDS or any other condition causing immunosuppression has increased susceptibility to Candida and other types of infections too. Acidophilus is one of the organisms that competes with Candida and decreases its population. Many studies have shown that oral and topical use (by douching) of acidophilus are effective to prevent and treat this condition.
Systemic candidiasis, or yeast hypersensitivity syndrome, is a condition that is not recognized by many allopaths. It is acknowledged by some practitioners of alternative and complementary medicine as a problem with broad-ranging consequences. This theory holds that some people have an allergic reaction to the yeast and/or its toxins, and that they can experience serious symptoms when the organism multiplies in the body to an abnormal degree. Fatigue, diarrhea, constipation, muscle pain, thrush, itching, mood changes, endocrine dysfunction, headaches, and tingling or numbness of the extremities are some of the symptoms that are reportedly associated with systemic candidiasis. A weak immune system may be more prone to allowing yeast to multiply, and large numbers of yeast can act to further suppress the immune function. Acidophilus, in combination with such nutritional supplements as essential fatty acids, is often recommended for the prevention and treatment of this syndrome.
Irritable bowel syndrome (IBS) is a functional disturbance of the lower intestine that can cause bloating, cramping, abdominal pain, diarrhea, constipation, and painful bowel movements. This condition is also known as spastic colon. One small study of the use of acidophilus to treat IBS showed more improvement in the treated group than in those who took a placebo. This is not conclusive evidence, but in view of the safety of the treatment and the scarcity of effective alternatives, acidophilus may be worth trying.
Traveler's diarrhea is sometimes suffered by people who consume contaminated food or water in other countries. Some evidence shows that regular use of acidophilus and other probiotics may prevent this condition.
High cholesterol levels
Recent evidence suggests that consuming Lacto-bacillus acidophilus L1 can be effective in lowering blood cholesterol. The February 1999 issue of the Journal of the American College of Nutrition reports on two studies done at the University of Kentucky. Subjects who consumed the yogurt containing L. acidophilus L1 had cholesterol levels drop by 2.4% in one study and 3.2% in the other. Although the percentages are small, the effect on the risk of heart disease could be significant.
A study published in the December 1998 issue of the Brazilian Journal of Medical and Biological Research found that acidophilus induced a nonspecific immune response in experimental mice. Acidophilus is sometimes recommended as an immune booster for people, although the effect has not yet been documented in humans.
Acidophilus is taken by mouth. It is available as powder, liquid, tablets, or capsules, and is also present in some types of milk, kefir, yogurt, and some cheeses. Frozen yogurt does not contain live probiotics. Check product labels to see whether live organisms are present. The bacteria are killed by pasteurization. Probiotic products are most potent when kept refrigerated. The potency of a given preparation is usually expressed as the number of organisms per capsule. A usual dose of acidophilus is 1–10 billion organisms, divided into three doses per day.
People who are lactose-intolerant may also not tolerate acidophilus.
The initial use of acidophilus may cause an increase in intestinal gas, which decreases with continued use of the product.
Bratman, Steven, and David Kroll. Natural Health Bible. Rocklin, CA: Prima Publishing, 1999.
Jellin, Jeff, Forrest Batz, and Kathy Hitchens. Pharmacist's letter/Prescriber's Letter Natural Medicines Comprehensive Database. California: Therapeutic Research Faculty, 1999.
Lininger, Skye. The Natural Pharmacy. Rocklin, CA: Prima Health, 1998.