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Brian Collura


Yo-Plus and probiotics Bifidobacterium Lactis


        Yogurt has been a part of culinary culture for over 4,000 years, and yet today, not much has changed about it aside from removing an ‘h’ from its spelling. It is created from fermented milk, a process that creates a culture of bacteria in the yogurt ( While this of course sounds like a bad thing, these particular bacteria are good for you. In fact, our bodies have more bacterial cells in our digestive system than human cells (! Recently, the yogurt manufacturer Yoplait has released a line of yogurt called Yo-Plus, which advertises itself as yogurt containing important bacterial cultures that promote health and digestion. Is this true? How is it different than other yogurts that also contain bacteria? And finally, does it work?

Even though you can’t see it, there are bacteria in all yogurt.



        Your digestive system includes many strains of what are considered “good” bacteria. These bacteria serve to help your body extract nutrients from food, as well as to defend against incoming “bad” bacteria that may enter through your mouth, a prime entrance for pathogenic invaders. Their role in both digestive health as well as in aiding the immune system makes them very important, a fact that can easy be explained by the sheer numbers of them in your body: “Over 1,000 species of bacteria may be present in the human colon at concentrations reaching 100 billion to one trillion per gram” (!

        According to Yoplait, Yo-Plus carries a “special combination of probiotic cultures and fiber, plus vitamins A and D,” to help balance your digestive and immune systems ( These systems can supposedly become unbalanced for many reasons, including a poor diet, stress, or certain medications, among other causes. When you are out of balance, the resulting irregularity and general feelings of ill-health may simply add to you current stresses! Therefore, Yoplait’s simple solution is one cup of their product a day, which will progressively balance your digestive and immune systems, and thus alleviate your symptoms.

        As we know, yogurt inherently contains live cultures that are considered to be good bacteria. For instance, all of Yoplait’s yogurts contain strains called S. thermophilus and L. bulgaricus ( However, what differentiates Yo-Plus from others is Bifidobacterium lactis, or Bb-12. It is a probiotic (literally, “pro life”), which means that it is a body-friendly bacterium that has a positive health effect (Leahy et al., 2005). It is the most common bacteria in the digestive systems of very young children, but their numbers decline as we age. According to Yoplait, sufficient amounts of Bb-12 can regulate diarrhea and constipation. Yo-Plus also contains fiber, in the form of inulin, which is broken down as “food” for the Bb-12 to keep it alive longer as it passes through the digestive system. As the Bb-12 travels along the digestive tract, it replaces bad bacteria, pushing it out of its place and thereby realigning the ratio of “good” to “bad” bacteria in favor of the good ones. While it may take up to a few weeks to notice a difference in health and digestion, Yoplait still claims a substantial and relevant effect on regularity and digestive health.

Strain of Bifidobacteria.


Background and Evidence

        Now that we know a little bit about the basics of “good” bacteria and some more specific claims Yo-Plus makes of its probiotics, we can take a look at where these claims come from. As it turns out, people have been interested in the effects of these Bifidobacterium since the turn of the 20th century. Henry Tissier noticed a difference in the number of Y-shaped “bifid” bacteria between the feces of infants who breast-fed versus those who drank formula. He proposed then that these bacteria could be used as a treatment for diarrhea, but the research was somewhat scattered and the concept was disregarded until the 1980s, when new identifications of probiotic cultures brought about a resurgence of interest in this concept (Leahy et al., 2005). Research began once again, and some food producers in Japan took early advantage of the new data to create the first foods specifically enhanced with probiotics.

        More than 20 years later, we know a great deal more about Bifidobacteria and their potential effects. Saavedra et al (1994) found that infants who consumed a formula with Bb-12 and S. thermophilus (both of which are found in Yo-Plus) had a reduced risk of diarrhea, down to 7% compared to the 31% in infants consuming typical formula. Marteau et al (2001) studied the effects of combining 4 different probiotics (Bb-12 among them) and their effect on Traveler’s Diarrhea. Traveler’s is an acute diarrhea affecting “about half of the travelers who visit high risk areas”. In one study of travelers to Egypt, the frequency was cut from 71% to 43% by consuming the probiotic mixture.

        Other health benefits have been noted as well. Leahy et al (2005) summarizes many uses of Bifidobacteria, including Antibiotic-related diarrhea. When you take oral antibiotics, many good bacteria are also affected, thereby hindering the digestive system’s ability to perform well. It has been shown that Bifidobacteria (especially B. longum) helps to regenerate these lost bacteria.     

        These probiotics can also help directly against “bad” bacteria. Studies have shown Bifidobacteria as a treatment against Clostridium difficile, which has been known to cause digestive woes. There have even been studies in animals supporting the idea that certain Bifidobacteria could protect against lethal amounts of Salmonella and E. coli, though these have not been tested on human subjects (Leahy et al., 2005).

        There may even be evidence of probiotic treatment against Colorectal Cancer (CRC). Changes in intestinal microorganisms may produce enzymes that are correlated with procarcinogen conversion, which would in turn create cancerous cells. Bifidobacteria may diminish these initial changes, and thus potentially help in the prevention of Colorectal Cancer. Granted, very limited data is available to this end, and only animal studies have been performed (Leahy et al., 2005).

        While most of the topics of study have focused on Bifidobacterial effects on diarrhea, there have been a smaller number on constipation as well. These results are less convincing, however. There is reason to believe that PMS-related constipation may readily be treated with probiotics, but these effects were not shown using the Yo-Plus strain, B. lactis, and not a lot of data is available to make more claims (Leahy et al., 2005).


        Many or all of Yoplait’s claims are indeed clinically based, and their brief assertions are indeed backed by the clinical data. However, much of the probiotic Bifidobacteria research has been on other strains than Yo-Plus’s B. lactis, notably B. longus and others of the more than 20 identified strains. Many of these focus on infant use, due to its prevalence in the digestive system of very young children, and is almost always in regards to diarrhea and not with constipation. Also, much of the Bifidobacteria’s genome and other very specific details of Bifidobacteria are as of yet unknown, so there is still a chance that the results seen in clinical trials are caused by some other factor.
    Still, every indication gives this product credibility for safety, so there is no reason to fear any harmful effects. Also, the chances are still strong enough in favor of the product’s effectiveness that trying it for intestinal health and regularity, at least to a mild to moderate degree, is well worth it if it may mean combating digestive discomfort. This is especially true in older people (as these probiotics dwindle in our body with age) and those with symptoms of diarrhea. Further research into the area of Bifidobacteria may yield new treatment options for us, but likely will not discredit the major benefits that have been found so far.


Literature Cited


Leahy SC, Higgins DG, Fitzgerald GF, van Sinderen D.  Getting better with    Bifidobacteria.  Journal of Applied Microbiology 2005; 98:1303-1315.

Marteau PR, et al. Protection from gastrointestinal disease with the use of probiotics. Am         J Clin Nutr 2001; 73(suppl):430S-6S.

Matsumoto M, Tadenuma T, Nakamura K, et al. Effect of Bifidobacterium lactis LKM         512 yogurt on fecal microflora in middle to old aged persons. Microb Ecol Health Dis 2000; 12:77-80.

Saavedra, J.M. et al. Feeding of Bifidobacterium bifidum and Streptococcus thermophilus         to infants in hospital for prevention of diarrhea and shedding of rotavirus. The         Lancet 1994; 344:1046-1049.

Shioya M, Nakaoka K, Iiuzuka N, et al. Effect of fermented milk containing         Bifidobacterium lactis FK 120 on the fecal flora, with special reference to         Bifidobacterium species, and fecal properties in healthy volunteers. J Nutritional         Food 2000; 3:19-32.





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