But what about the health claims? Does adding probiotics to food and our diets really make us healthier?
There are more than a hundred-billion bacteria (per gram) residing in the large intestine alone (a total of about a million-billion, which is about 10 times more cells than the total number of human cells in the body), says Dr. Bob Hutkins, a microbiologist and professor in the department of food sciences and technology at the University of Nebraska. If you're beginning to feel like a giant parasite host, don't worry these bacteria aren't necessarily the disease-causing types (although some are). Many of the bacteria are friendly, and can have a beneficial effect on the body, assisting with digestive problems such as lactose intolerance and diarrhea as well as bolstering the immune system.
Probiotics are considered friendly bacteria, and by introducing them to the gastrointestinal tract through diet or supplements, the idea is one of bacterial domination, according to Catherine Wilbert, local nutritional expert and owner of Vitality Juice, Java and Smoothie shops.
"When I explain to people why [probiotics] are important, I say it's because there are so many that live in your gut that are not so good. It's basically like a battle; the one who has the greatest troops prevails," she says. "The more good guys you have and the more they outnumber the bad guys, then the good guys win."
Winning in this case means improved digestion, and if you're one of the 30 to 50 million Americans who are lactose intolerant, scientific studies demonstrate that probiotics, also called microflora, may help. Notice the operative word here is "may." Taking probiotics doesn't guarantee the problem will go away.
"Even the research is equivocal," Hutkins says. "It doesn't help 100 percent of the time."
Because there is a limited amount of space in the gastrointestinal tract, large numbers of probiotics interfere with bad bacteria and pathogens, not allowing them enough room to grow. According to Hutkins, however, even though there are huge numbers of bacteria present, it's a very stable environment where it's difficult for any bacteria, including probiotics, to colonize. Once a person stops eating probiotics, these microorganisms don't stick around; they are excreted out of the body. So just like a diabetic takes daily doses of insulin, those who are lactose intolerant will require a regimen of probiotics.
Extending Wilbert's military metaphor, there's a constant need for reinforcements and the incoming forces have to number in the billions in order to be effective. Professor Kayanush Aryana of the Department of Food Science at LSU's Agricultural Center, studies probiotics and how they relate to yogurt, the most common probiotic food. He says that high amounts of probiotics are required not only so they will outnumber the pathogenic bacteria, but also because of the path to the lower gastrointestinal tract. In order to reach the lower intestine, the probiotic cells have to pass through the stomach, which is full of acids that kill bacteria.
The same goes for probiotic supplements, Wilbert says. If a probiotic supplement contains 50 billion probiotic cells but the capsule doesn't protect the probiotics, the result is 50 billion dead probiotic cells in the large intestine. Wilbert still thinks that probiotic supplements are a good idea the average person doesn't get enough microflora in their diet, which is why most Americans have digestive problems but consumers should look for probiotics that are microencapsulated or coated for release in the large intestine after passing through the stomach.
Hoping to improve their digestion, millions of Americans have turned to yogurt. In order to make yogurt, under standards established by the Food and Drug Administration, manufacturers must use the live bacteria cultures Streptococcus thermophilus and Lactobaccilus bulgaricus. Interestingly enough, Hutkins says, scientists currently are debating whether or not these two bacteria are actually probiotics (the jury is still out). He reports that in the past five years, likely due to the growing amount of scientific literature supporting the use of probiotics for digestive problems, more and more yogurt is being produced that is fortified with other bacteria that have nothing to do with taste or texture.
"Those (bacteria) are (Lactobacillus) acidophilus and the bifida and those are there strictly for the health benefits," Hutkins says.
Wilbert, Hutkins and Aryana all agree there's been an adequate amount of scientific reports in peer-reviewed journals to substantiate using probiotics. Food companies are using this information to advertise the health benefits of their products. Dannon makes Activia yogurt, which contains the two required yogurt cultures S. thermophilus and L. bulgaricus, plus bifidobacterium and the company's own patented strain of probiotic, Bifidus Regularis. The Activia Web site offers to consumers a challenge: "Eat Activia every day for two weeks. If it doesn't help naturally regulate your digestive system and taste great, we'll refund your purchase price up to $12." Since Activia's introduction in 2006, the yogurt has accounted for sales of more than $100 million in the United States alone.
Trish Weiner, a California woman, took the two-week challenge, didn't experience any positive results and in January filed a class-action lawsuit against Dannon. Weiner is seeking damages for herself and others who bought Dannon's Activia, Activia Lite and DanActive. She states in the lawsuit that Dannon's health claims regarding Bifidus Regularis are "false, misleading and reasonably likely to deceive the public." Weiner's suit also says that Dannon created a massive advertising campaign that used "deceptive names for its proprietary strains of bacteria," including Bifidus Regularis. The lawsuit goes on to assert that Dannon used the misleading information to "justify" charging 30 percent more for Dannon products than other companies charge for their yogurt products.
Hutkins considers the lawsuit to be frivolous. He recently reviewed the Activia packaging and believes that Dannon went to pains to ensure consumers knew that if the product didn't work, they would get their money back. Although he isn't a lawyer, Hutkins feels Dannon's offer for a full refund is sufficient, adding that Dannon's scientific assertions have been published in highly regarded scientific journals (specifically, Alimentary Pharmacology and Journal of Applied Microbiology).
"I sort of compare it to a person that sues Tylenol because their headache didn't go away," he says.
What Hutkins does point out, though, is that Dannon created the name for its probiotic strain, Bifidus Regularis, because it sounds like something that would help regulate the digestive system. The real name is Bifidobacterium animalis DN-173 010. Not exactly mouthwatering, is it?
As an expert on probiotics, Hutkins isn't convinced that one yogurt is really better than another. He maintains that the most popular yogurts are still the store brands and that they should be fine for the average consumer. He's not against people who have constipation eating Activia to help the condition "There's an improvement in regularity [for] people eating that culture," he says but many of the live bacteria cultures in the store brands have undergone rigorous testing as well. It's up to consumers to determine which yogurt works best for them.
"A lot of these are self-experiments," Hutkins concludes.
Wilbert doesn't think that yogurt is a good source of probiotics anyway. She says that other foods like kefir (a fermented milk beverage), kombucha (a fermented tea), and tempeh (a fermented food made with soybeans) contain more live bacteria cultures. Eating a little yogurt isn't enough, she says.
Aryana approaches the idea of probiotics a little differently. For his experiments with adding probiotics to yogurt, he's not only considering the health advantages of the probiotics, he's also testing whether the yogurt is pleasing to the palate.
"You need to have the right balance, the right amount of bacteria in there to end up with the benefits and a good product," says Aryana. "Because, finally, it is a product that tastes good and has a good texture that the consumer is going to go for."
So in the case of probiotics, getting Americans to eat something that's proven to be part of a good diet is ultimately like trying to get a kid to eat vegetables. The parent can stand over the child and his dinner, saying endlessly that veggies are good for him, but that doesn't matter if those Brussels sprouts or broccoli don't taste good. And sometimes, that's enough to give the parents indigestion.