Having live bacteria and yeast in your food or dietary supplement may sound disgusting, but could actually be healthy. Known as probiotics, supplements containing microbes such as Lactobacillus acidophilus, Lactobacillus bifidus or bifidobacterium bifidum are marketed to improve the health of the intestinal tract, decrease the prevalence of vaginal, bladder and sexually transmitted infections, increase immune functions, decrease cholesterol and lipid levels, and help prevent irritable bowel syndrome, food allergies, fatigue, depression and arthritis. These supplements, however, are not regulated by the U.S. Food and Drug Administration (FDA) for purity, viability or efficacy, and often do not contain any viable microorganisms at all. This is particularly true for the probiotics marketed as not requiring refrigeration. In addition, non-refrigerated probiotics often contain bacteria of unknown species, or potentially harmful species.

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Bartell Brand and Rite Aid Acidophilus

Bartell Drugs and Rite Aid both sell probiotic supplements not requiring refrigeration. They are both labeled as containing Lactobacillus acidophilus. In addition, Rite Aid also supposedly contains Lactobacillus bulgarium and Bifidobacterium bifidum. Unfortunately, according to a 2003 study by Bastyr University, neither Bartell's acidophilus nor Rite Aid's acidophilus contain Lactobacillus acidophilus, Lactobacillus bulgarium or Bifidobacterium bifidum. Rather, they contain Lactobacillus rhamnosus. While this is not the species labeled on the product, Lactobacillus rhamnosus does have beneficial effects for humans, helping with digestion and immunity as well as decreasing antibiotic-associated diarrhea in children.

Nature's Bounty Acidophilus

Nature's Bounty Acidophilus is also marketed as a probiotic supplement not requiring refrigeration. Unfortunately, when tested in 2003 by researchers from Bastyr University, this supplement contained no viable Lactobacillus acidophilus. The supplement did, however, show gram-positive rods in the gram-stain test, indicating there were nonviable organisms of indeterminate species contained within the supplement. This indicates the supplement may have had a viable organism at one time, but it was not Lactobacillus acidophilus.

Natrol Acidophilus

Similar to Nature's Bounty Acidophilus, Natrol Acidophilus is marketed as a probiotic containing Lactobacillus acidophilus that does not require refrigeration. However, the 2003 study by Bastyr University indicates that although nonviable organisms of indeterminate species showed up on the gram-stain test, no viable Lactobacillus acidophilus in the probiotic supplement was found.

Natural Brand Acidophilus Plus

Natural Brand Acidophilus Plus is another probiotic supplement requiring no refrigeration. Tests by Bastyr University in 2003 revealed that not only did this supplement not contain the Lactobacillus acidophilus indicated by the label, it also did not contain any viable organisms of indeterminate species either. Whether it ever contained any organism is not clear.

Safeway Select Acidophilus Plus

The supermarket chain Safeway sells "Safeway Select Acidophilus Plus." According to the label, this probiotic does not require refrigeration. Unfortunately, Bastyr University discovered the organisms present were not the Lactobacillus acidophilus, Bifidobacterium longus or Bifidobacterium bifidum as the label indicated, but rather Lactobacillus gasserri 3. Lactobacillus gasserri is a relatively "good" bacteria, in that it is normally found in your gastrointestinal tract. It has been associated with the reduction of fecal mutagenic enzymes helping keep normal healthy bacteria in check, adherence to intestinal tissues and stimulation of macrophages which boosts the immune system and production of bacteriocins, toxins that inhibit the growth of other bacteria.


General Nutrition Center markets Kyo-Dophilus, a probiotic not requiring refrigeration supposedly containing Lactobacillus acidophilus, Bifidobacterium bifidum and Bifidobacterium longum. Again, this probiotic supplement contained none of these organisms when tested. In this case, three different species were detected: Lactobacillus gasseri, Enterococcus durans and Bifidobacterium infantis. While Lactobacillus gasseri and Bifidobacterium infantis may be beneficial, Enterococcus durans is associated with diarrhea, occasionally reported in human clinical infections.