Check out the dairy aisle of any major grocery store and you may think you've stumbled into a pharmacy. A growing number of yogurt companies are promoting the ability of their products to aid digestion, boost brain development and strengthen the immune system through the addition of probiotics.
Some yogurt brands have even started boasting the inclusion of docosahexaenoic acid, more commonly known as DHA, an omega-3 fatty acid associated with helping normal brain development.
The probiotic trend has proven so popular that the live micro-organisms can now be found in a wide range of products, including frozen yogurt, beverages and cereal.
But the credibility of health claims accompanying probiotic-infused foods suffered a blow this week when yogurt giant Dannon Co. Inc., a unit of Groupe Danone SA, agreed to make labelling changes and set up a fund of $35-million (U.S.) to pay back customers who purchased Activia and DanActive products for their perceived health benefits. The agreement was part of a settlement reached in a lawsuit launched against the company in the United States.
While the company said it did not admit any wrongdoing and stood by the scientific credibility of its products, some say it's valid to question the health assertions trumpeted by yogurt makers and other food manufacturers.
A major part of the problem is that the popularity of probiotics among consumers has attracted companies that may not have invested in research to prove their products have a health benefit, said John Bienenstock, professor of medicine and pathology at McMaster University in Hamilton.
"There's people jumping on the bandwagon and I think that's the problem that we've got," said Dr. Bienenstock, who is also director of the Brain-Body Institute at St. Joseph's Health Care.
Probiotics are live micro-organisms, or bacteria, that can deliver potential health benefits when consumed in adequate amounts, according to the World Health Organization. Research has shown that probiotics may help reduce urinary-tract infections and stomach discomfort, and boost the immune system of some individuals.
But there are many types of probiotic bacteria, and their health benefits vary. That means the benefits offered by foods infused with probiotics depend largely on the type, amount and combination added to a particular product - information that is often difficult to find or understand by consumers, said Wayne Miller, associate scientist at the Canadian Research and Development Centre for Probiotics, which is affiliated with the London Health Sciences Centre and St. Joseph's Health Care.
"Not all probiotics are the same," Dr. Miller said. "There's lots of promising research out there but I think we're hampered by the fact there's a lot of products out there that are called probiotic that don't have any research behind them."
Many companies add probiotics to their products that haven't been fully studied or analyzed to determine what, if any, health benefit they offer, Dr. Miller said.
He supports the research behind the Activia and DanActive brands that indicate they can aid in digestive health. Danone, which sells those brands in Canada, donated $7-million (Canadian) to the Canadian Research and Development Centre for Probiotics earlier this year.
Health Canada has attempted to clear the confusion surrounding probiotic health statements by issuing guidelines earlier this year designed to spell out when they can appropriately be used. A guidance document on the department's website said food manufacturers should name the specific probiotic culture used and limit claims to those that refer to maintaining or supporting bodily functions, such as "promotes regularity."
But the Health Canada policy has been criticized by some experts who say it doesn't require strong enough information from industry, such as rigorous evidence that the probiotic culture in question has a health benefit.
Dr. Miller said there are signs to help consumers determine which may be the better probiotic yogurt. He advised consumers to choose types of yogurt that list the specific probiotic bacteria used in the product. He also recommended going on the company's website or directly requesting scientific material that can back up health statements. Or consumers could consult with a family doctor who may be able to tell them if the evidence supporting certain probiotics exists.
Don't believe everything you read
Yogurt labels are carrying a growing number of health assertions, but experts warn not all may be as good as they appear. Here are some examples of popular statements and cautionary notes:
Probiotics: A major portion of yogurt brands on the market, as well as a growing number of other food products, boast the inclusion of certain probiotic micro-organisms. However, experts warn that not all probiotics offer health benefits and that they must be consumed in adequate doses to do any good. Consumers should choose brands that list the probiotics by name, and seek scientific research from the company.
Docosahexaenoic acid: Better known as DHA, this is an omega-3 fatty acid that is being added to products such as baby formula, yogurt and ice cream. The federal government allows food manufacturers that add DHA to their products to state that it "supports the normal development of the brain, eyes and nerves." But some critics say DHA-infused products, such as yogurt, contain only small amounts of the fatty acid, which may not be enough to confer any health benefit.