The benefits of Acidophilus are well known as more and more people gain improved health after taking Lactobacillus acidophilus supplements. It is the best know of all the probiotic Lactobacillus species and what a wonderful bacteria it is. It is a natural inhabitant of your mouth, gastrointestinal tract and vagina (if you have one!)
Not all strains of L acidophilus do all of these things although all strains will do you some good. In fact any lactic acid bacteria will do you a little good.
If you're looking for an acidophilus based supplement especially formulated to treat bacterial vaginosis, then Femanol might be worth trying trying. It also contains neem bark extract, garlic and a multitude of vitamins and minerals. Many women - but by no means all - have had excellent results with it. See my review on Femanol first.
Gy-natren Vaginal Health Kit contains an oral capsule of 2 billion cfu of Lactobacillus acidophilus NAS and a vaginal insert containing the acidophilus and boric acid. Most effective for yeast infection.
Diarrhea - Whilst the benefits of acidophilus include enhancing the general overall health of your gastrointestinal microflora, if you actually HAVE diarrhea, or you're travelling to some place where you just KNOW that you're going to get it, there are other Lactobacillus species that are probably more useful, for example Lactobacillus reuteiri and Lactobacillus rhamnosum strain GG (commonly called simply LGG) would benefit you better. Bifidobacterium has also been shown to be of help and many yogurts and supplements have the two together.
Got acne - this probiotic probably won't help much. There really isn't much research to support the claims that it does. The talk around the forums seems to suggest it gives people acne more times than it helped. Having said that, there are acne sufferers who swear it has helped. Both the Harvard Medical School and the Mayo Clinic cite "limited scientific evidence" although they're both incredibly conservative.
It can give you dental carries7. Sorry I have to tell you that, but hey, no bug is perfect, right! It combines with proteins found in saliva and food particles forming plaque, which digest sugars and produces acid, which dissolves the calcium and even tooth enamel.
If you're lactose intolerant then this probiotic might give you abdominal discomfort and gas (flatulence), although some research claims that if the level of live bacteria in the yogurt is HIGH ENOUGH, then "lactose maldigestors" (their words, not mine - I would never call you that!) are able to digest it.6
Overall, the health benefits of acidophilus FAR outweigh any downside.
1. Paturi G, Phillips M, Jones M, Kailasapathy K. Immune enhancing effects of Lactobacillus acidophilus LAFTI L10 and Lactobacillus paracasei LAFTI L26 in mice. International Journal of Food Microbiology, vol 115 issue 1 pages 115-118, April 2007
2. Beigi RH,Wiesenfeld HC, Hillier SL et al. Factors associated with absence of H202-producing Lactobacillus among women with bacterial vaginosis. Journal of Infectious diseases 191(6): 924-929 2005
3. Wood JR, Sweet RL, Catena A, Hadley WK, Robbie M. In vitro adherance of Lactobacillus species to vaginal epithelial cells. American Journal of Obstet Gynecol Dec 1;153(7): 740-3 1985
4. McLean NW, Rosenstein IJ. Characterisation and selection of a Lactobacillus species to re-colonise the vagina of women with recurrent bacterial vaginosis. Journal of Medical Microbiology 2000 Jun 49 (6)
5. Marteau PR, de Vrese M, Cellier CJ, Schrezenmeir J. Protection from gastrointestinal diseases with the use of probiotics. American Journal Clinical Nutrition 2001:73:430S-436S
6. Pelletier X, Laure-Boussuge S, Donazzolo Y. Hydrogen excretion upon ingestion of dairy products in lactose-intolerant male subjects: importance of the live flora. European Journal of Clinical Nutrition 55: 509-512 2001
7. Shivakumar KM, Vidya SK, Chandu GN. Dental caries vaccine. Indian J Dent Res. 2009 Jan-Mar;20(1):99-106.