Rachel’s line of gourmet yogurts is probiotic, enhanced with Omega 3s, kosher...and fashionable. Why didn’t they put the words “probiotic” on the front of the container? They’d sell more to probiotic-hungry Americans! Read our full review of Rachel’s yogurt.
Digestion of food begins as soon as you begin to eat. Chewing breaks food down into smaller particles with greater surface area, rendering the food easier for digestive enzymes (including those in your saliva) to act upon. Food passes down the esophagus into the stomach, where it’s combined with a highly acidic mixture of more digestive enzymes and hydrochloric acid. This mixture is called “chyme”; it’s pumped out of the stomach and into the small intestine, where the chyme combines with yet more enzymes and bile. It’s in the small intestine that the breakdown of proteins, carbohydrates and fats concludes. Most nutrients are also absorbed in the small intestine.
The digestive system organs in the abdominal
cavity. Image courtesy of the National Library of Medicine and the National Institutes of Health.
Within four to six hours of ingestion, what’s left of the food passes to the large intestine, also known as the colon. Here, waste accumulates and water and electrolytes are absorbed. Every 24 to 48 hours, what has become fecal matter passes out of the system via the rectum.
All bacteria (whether friendly or pathogenic) are minute living creatures—single-celled organisms that live all over the outside and the inside of the human body. The environment is not ideal for these bacteria in the stomach or upper small intestine, but toward the lower small intestine, and especially in the colon, much higher populations are achieved. Humans have at least several hundred different kinds of bacteria (some sources believe many times that number) living in their intestinal tract alone; these “bugs” number in the hundreds of billions, if not trillions. Most are not pathenogenic, but there are bacteria present in the intestinal tract whose function is currently not known. The bacterial environment here is highly complex and can change rapidly.
Many factors, such as diet, stress, the taking of antibiotics and even aging, can affect the balance of these bacteria. The balance can shift in favor of beneficial microbes (which would result in a lower pH or greater acidity, an unfavorable environment for pathogens), or in favor of harmful microorganisms. When the latter occurs, health issues may result. For example, when antibiotics are ingested, they may kill beneficial bacteria, as well as pathogens. When normal intestinal flora populations are thus altered, the resulting imbalance may be conducive to the introduction and/or multiplication of pathogens. This may cause antibiotic-associated diarrhea (AAD), which in its serious forms can result in hospitalization.
The huge numbers of intestinal tract microbes play roles both within and apart from the digestive process. They help to complete the digestion of any food components not digested in the small intestine (including the breakdown of lactose in lactose-intolerant individuals or some enzyme-resistant fibers). Some of these microbes produce vitamins. Microbes normally seen in the intestinal tract can reinforce the intestinal lining’s function as a “barrier,” preventing bacteria associated with the intestine from passing into the bloodstream (“leaky gut” syndrome). It is also thought that the majority of the human immune system, some 50% to 70% depending upon whose estimates you credit, is based in the intestinal tract, so keeping sufficient populations of beneficial bacteria there may play a role in preventing some diseases.
Earlier probiotic research concluded that for any bacteria to have an effect on the human host, it must attach itself to the lining of the gastrointestinal tract-something known as “bacterial adherence.” It was believed that as probiotic cells age, they could be mutated, so that they did not stick to the lining of the gastrointestinal tract as well.
Cuinneog ProBiotic Butter is the world’s first ProBiotic Butter, made in Ireland. See more probiotic foods below, and read more about the butter at
If these probiotics lost their grip, there was a possibility for pathogens to establish themselves in place of the probiotics. Once established, pathogens could act in several ways to potentially harm the host. More recent research has not supported this bacterial adherence theory, though. Dr. Robert Martindale, Professor of Surgery at Oregon Health and Science University, asserts that probiotics function in the gastrointestinal tract, especially the colon, by “competitive inhibition.” That is, the tremendous number of bacteria growing there, whether beneficial or harmful, must compete to survive. And one way for probiotics to survive, or out-compete, any toxins is by destroying them.
An article by Goran Molin in the American Journal of Clinical Nutrition states that “lactic acid fermented foods have made up a significant portion of food intake by humans for a long time and still do so in many developing countries.” Molin adds that lactic acid fermentation is a very simple method of food preservation that can be relied upon as safe, and prior to the Industrial Revolution, “was used just as much in Europe as it still is in Africa.” The author further notes that archaeological evidence indicates ancient use of lactic acid fermentation for foods, probably plant-based at first, followed by dairy-based as well. It’s possible the human gastrointestinal system evolved to expect a daily supply of live lactic acid bacteria. During the 20th century, the people of westernized nations stopped eating such large quantities of lactic acid fermented foods, and Molin believes this may have led to gastrointestinal issues, “perhaps even immunologically dependent ones.”
Forms of Probiotics Available to Consumers
Probiotics are most often ingested by mouth and can be obtained from foods or supplements. It should be easy to tell the difference between the two, but in recent years the line between food and supplement has blurred with the rise of functional foods. According to Ruth DeBusk, PhD, RD, the increasing interest in functional foods in the U.S. is being stimulated by potent forces in the market. These include a population growing older, ever-increasing health care costs, consumer demand and an accompanying change in the way food is perceived (consumers want foods to do more than simply provide sustenance), advances in knowledge supporting the concept that diet plays a crucial role in overall health, a changing regulatory climate, and technical advances in the food industry allowing development of foods that supposedly promote better health.
The majority of foods containing probiotics are at least partially fermented, although “cultured” seems to be a term with greater social acceptance. In the U.S., though not everywhere else, the most popular probiotic-containing foods are dairy products. In part, this is because consumers are most familiar and most comfortable with the idea of consuming “cultured” dairy products.
There is much debate over whether probiotics need to be ingested in a dairy base. Some credit a dairy base with providing protection essential for these bacteria to survive the strong acids of the stomach before they reach the intestinal tract, and also declare that dairy provides a source of food so the bacteria can multiply rapidly once they reach the gut. But there are probiotic foods available elsewhere in the world that do not contain dairy products, including a fermented beverage called togwa in Tanzania, made from sorghum or corn, and Sweden’s ProViva probiotic drink, which has a base of oatmeal and a little malted barley.
In at least one study, togwa has been shown to have some beneficial effects on infant diarrhea; ProViva and its related products (ProViva Shot and ProViva Active) claim to reduce the flatulence that “is a common problem in IBS-related diseases.” And Mary Ellen Sanders, Ph.D. and consultant for Dairy and Food Culture Technologies, states that, regarding probiotic delivery, “many controlled studies have documented effects of probiotics not delivered in dairy ingredients.” But she adds that hard evidence comparing different modes of delivery of probiotics or even different product formats is lacking at this stage.
Probiotic supplements are available in multiple forms, including capsules, chewable tablets, freeze-dried powders, wafers and beverages. Our focus here is primarily on probiotic-containing foods.
Yogenfrüz is a frozen yogurt manufacturer that also produces yogurt for I Can’t Believe It’s Yogurt, Swensen’s and other brands. It offers a probiotic frozen yogurt in addition to no fat yogurt, no sugar yogurt, smoothies and other yogurt products.