Probiotics are hot. From Jamie Lee Curtis gushing about the digestive benefits of Dannon's Activia® yogurt to nutritional bars touting their immune-boosting formulas, probiotics are carving a substantial place for themselves in the market. As beneficial as they are, there are several challenges when it comes to formulating with probiotics; manufacturers must take care to select and deliver the most applicable strain with substantiated health benefits.
Probiotics, typically beneficial bacteria found in gut flora and, less commonly, certain types of yeast, are a key to maintaining gut health, an effective digestive process and a strong immune system.
"Probiotics may be defined as food supplements containing concentrates of defined strains of living microorganisms that, on ingestion in certain doses, exert health benefits beyond basic nutrition. The concept of probiotic foods is based on the fact that the micro flora in the gastrointestinal (GI) tract has a significant role in the health status of an individual, which is influenced by the diet consisting of organisms," explained Luis Echeverria, new business development manager, Pharmacenter.
Strains of lactic acid bacteria, Lactobacillus and Bifidobacterium, are the most commonly-used probiotic bacteria in the nutraceuticals industry. "Across the globe, about 20 probiotic strains, singly or in combination, [are used], mainly Lactobacilli such as L. acidophilus, L. casei and L.reuteri," said Lakshmi Prakash, Ph.D., director of technical services, Sabinsa Corp. She added probiotic yeast culture Saccharomyces boulardii is popular for use in dietary supplements, functional foods or mainstream food products.
While probiotics may be making headlines today, they are not a new idea, according to Prakash. "Ancient physicians in the Near and Middle East prescribed soured milk [which contains lactic acid bacteria] for appetite stimulation, as well as in the management of diseases, including tuberculosis, GI disorders and liver troubles. Contemporary interest in probiotics can be partially attributed to [Russian microbiologist Ilya Ilyich Mechnikov's] theory of longevity, which associated prolonged youth and a healthy old age, common in Balkan peasants of those times, with the use of cultured milks in their diet."
Today’s standard American diet doesn’t generally deliver these types of fermented foods that can enhance probiotic colonization. The situation is further exacerbated by other factors, according to S.K. Dash, Ph.D., founder of UAS Laboratories. In his book A Consumer’s Guide to Probiotics (Freedom Press, 2005), he wrote: “A number of factors are responsible for the lack of friendly cultures in our intestinal tract. Beneficial microflora are reduced by excessive use of antibiotics, chlorinated water, food preservatives, junk foods, and pollution in our environment.” But their right probiotic “recipe” for good gut health is very specific. As Dash wrote: “A probiotic supplement can only be effective if it contains the right strain(s), in the right number (potency), in the right condition (viable) and in the right formulation.”
Health Benefits of Probiotics
Indeed, probiotics have been shown to have several health advantages, GI health being the most popular. "Receiving live 'bugs' to the gut will certainly create numerous health benefits, such as improved daily bowel habits, correcting constipation or diarrhea, improved skin conditions and overall better general health," explained Tony Serra, sales representative for Mitsui and Co.
Hui Zhu, Ph.D., laboratory manager, Specialty Enzymes and Biochemicals Co., echoed Serra's statements, noting, "These microorganisms benefit their host by maintaining intestinal homeostasis, competitive exclusion of pathogens, production of antimicrobial compounds, promotion of the intestinal barrier function, immune modulation and some very promising results in the area of inflammatory bowel disease."
In a 2008 review from Institut National de la Recherche Agronomique, Nouzilly (Tours), France, researchers found Saccharomyces boulardii has beneficial effects in the prevention and the treatment of intestinal infections, and in the management of inflammatory bowel disease (IBD).1 All these diseases are characterized by acute diarrhea; administration of the yeast, either alone or in combination with an anti-biotherapy, was shown to significantly decrease the duration and the frequency of diarrhea. However, a similar review admitted that, while some clinical studies have shown the therapeutic effects of probiotics in the treatment of IBD or prevention of allergic disease, researchers have not yet determined their exact role.2
Probiotics have also been shown to play a protective role in colon cancer, according to a 2001 review from the Institute for Nutritional Physiology, Karlsruhe, Germany.3 Researchers found ingestion of viable probiotics was associated with anti-carcinogenic effects, one mechanism of which is the detoxification of genotoxins in the gut. They added, newer studies showed short-lived metabolite mixtures isolated from milk that was fermented with strains of L. bulgaricus and Streptococcus thermophilus are more effective in deactivating risk factors of colon carcinogenesis than are cellular components of microorganisms. In spite of this, a 2006 review from the University La Sapienza, Rome, stated there is not enough specific evidence that probiotics are useful against cancer.4 Researchers noted, "In our search of the literature, few and conflicting epidemiologic data regarding the impact of fermented dairy products consumption in humans have been gathered. There are no positive data from interventional studies so far. Therefore, even though an ample body of evidence supports the potential anti-carcinogenic action of probiotics on the basis of the results obtained in both in vitro and in vivo models, further evidence is very much needed."
Dash, however, noted in his book that probiotics do have a clear role to play in prevention of colon cancer. He wrote: “We don’t know precisely how probiotics exert their anti-cancer benefits, but believe that by enhancing populations of bifidobacteria, this may result in direct removal of procarcinogens, indirect removal of procarcinogens, or activation of the body’s immune system.”