Your gut is home to trillions of microorganisms. Known as your gut microbiota, these friendly bacteria and yeasts help you digest food, produce vitamins and function as a vital part of your immune system. Consuming probiotics by eating yogurt is one way to get more of these helpful bugs into your system, but over-the-counter probiotic supplements are also gaining popularity. Yogurt is the most popular probiotic food source, but pills can also be a good option. Ultimately, your choice of probiotic source may depend on your food preferences and the type of probiotic you need to consume.
A product of fermented milk, yogurt naturally contains probiotics from the species Lactobacillus bulgaricus and Streptococcus thermophilus. Additional live bacteria including the strains acidophilus and bifidus are commonly added to enhance yogurt’s probiotic content. These same species can be found in probiotic pills. If you want to supplement these strains, both yogurt and pills may provide what you need. A study published in the December 2010 issue of “International Journal of Food Microbiology,” studied human saliva and fecal samples after either yogurt or probiotic pills were consumed, and determined that both provided the body with comparable amounts of microorganisms. If, however, you are looking to supplement with a probiotic strain not found in yogurt, your options include taking supplements or incorporating another food source known to contain these probiotics.
Probiotics are fragile -- easily destroyed by heat and acidic environments -- and foods and supplements must be carefully produced and stored to reap the benefits of live microorganisms. Foods or supplements with live probiotics have a short shelf life and require refrigeration, and freeze dried supplements -- which also have an expiration date -- must be kept dry and at room temperature. In order for probiotics to provide any health benefits, they also need to survive the harsh digestive process, an environment designed to kill bugs that may cause illness.
The good news is that both pills and yogurt are known to provide live bacteria to the intestines. Milk products, including yogurt, are known to buffer the acid in the stomach, which can protect these microorganisms as they make their way through the digestive tract. Probiotic pills can be encapsulated so more bugs make it through the stomach alive, and taking non-enteric coated pills with or 30 minutes before a meal offers a better chance of probiotic survival in the gut, as reported in the December 2011 issue of “Beneficial Microbes.”
Emerging research suggests that yogurt, however, may be an better option than pills. A study published in the July 2015 issue of “Applied and Environmental Microbiology” showed mice with inflammatory bowel disease had less disease activity after being fed a milk-based Lactobacillus probiotic, compared to probiotics in a medium that represented a pill form. This suggests the milk or yogurt matrix can improve the effectiveness of this type of probiotic, although more quality studies are needed. Prebiotics -- the food source necessary to keep gut bacteria thriving -- are found in many plant foods, and are added to some yogurts. An article published in the 2012 issue of “Annals of Biological Research” compared yogurts with different concentrations of the prebiotic inulin, and noted that higher levels of inulin were linked to better probiotic survival, although the survival verified in a simulated, not actual human gut.
While probiotic-rich yogurt can be a very good source of live bacteria, some yogurts are not produced to be high in probiotics, or are heat treated. As a result, some yogurts do not contain live microorganisms. High quality yogurts can be identified by a voluntary labeling claim indicating they contain live and active cultures, or by the probiotic strains on the ingredient list. Supplements have more label clarity, as the specific strains and dose based on colony forming units or CFU’s are listed on the label, allowing you to find the type or dose recommended by your doctor. Probiotic supplements are not regulated by the same standards as medications, instead they are often sold as dietary supplements -- and less proof of safety and effectiveness applies.
Unless you have a milk allergy or a known intolerance to yogurt, eating more probiotic-rich yogurt is a relatively safe and healthful dietary change. As with any dietary supplement, speak to your doctor before starting probiotic pills to treat a medical condition. Also talk to your doctor first if you have preexisting health problems, take any prescription medications, or plan to give probiotics to infants with immature immune systems. If you have been told you have a weakened immune system, probiotics may not be advised as they may increase your risk of certain infections. A dietitian can provide you with more information about probiotic-rich foods and ways to increase prebiotics and probiotics naturally.
Reviewed by: Kay Peck, MPH, RD