What Is Acidophilus Probiotic Complex?

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No matter what your digestive problems, probiotics may help to restore the natural bacteria balance in your gut. Acidophilus is a particularly effective and widely used probiotic strain, and is found in food like yogurt, tempeh and miso. You can also supplement your diet with live active cultures in pill form by taking an acidophilus probiotic complex, but not all acidophilus supplements are created equal.

Probiotic Complex

An acidophilus complex contains the Lactobacillus acidophilus bacteria and may or may not contain other bacteria strains that work in harmony or provide nourishment or additional protective measures that allow the acidophilus bacteria to work to utmost efficiency. Acidophilus is only one kind of beneficial bacteria. Other lactobacilli like L. casei and L. bulgaris, and the different strains of Bifidobacterium, are also beneficial to the digestive tract, and may be included in a complex, as opposed to a straight acidophilus supplement.


Once you swallow an acidophilus supplement, the pill goes through the usual digestive process, liberating the bacteria. These bacteria make their way to your intestines, but instead of passing through as usual, they adhere to your intestinal wall. Here they establish residence and help break down food, producing chemicals like lactic acid and hydrogen peroxide. These chemicals make your intestinal environment hostile to pathogens that could potentially cause problems, which keeps your digestive system running smoothly. Acidophilus is also useful in preventing the diarrhea associated with antibiotic use -- antibiotics kill all bacteria, not just the bad ones, so acidophilus helps repopulate your gut with the good bacteria to keep your intestines safe.


Follow the instructions on the probiotic label, but avoid supplements that don't list the number of colony-forming units, or CFUs, in each dose. This is the only way to know how much active bacteria you are getting. The dose depends upon the reason for supplementation, and can range from 1 billion to 15 bilion CFUs per day. Start your probiotic gradually to avoid unpleasant side effects like gas and bloating, and consult your doctor for the appropriate dose for your condition.


Probiotics are generally seen as safe, but labeling laws are lax. Probiotic supplements must be formulated in such a way that the bacteria survive processing, storage, transport and digestion so they reach your intestines alive. Then they must be able to adhere to the intestinal walls to perform their work. Choose a reputable brand with a quality assurance guarantee -- ask your doctor or pharmacist for a recommendation. There is no guarantee that the bacteria in any given brand are even what the label claims them to be. A 2002 study in the "Journal of Dairy Science" found that acidophilus probiotics were the most likely to be mislabeled, as quality assurance testing for acidophilus bacteria is complex. If the probiotic complex you choose doesn't work for you, it may be an indication of improper manufacture or labeling. Instead of giving up on probiotics, try another brand. People with weakened immune systems or who are taking sulfasalazine should consult their doctors before taking an acidophilus complex.