Beneficial Bacteria: All About Probiotics

Danielle Rosenfeld, MS, RD, LDN, member of the Penn Metabolic and Bariatric Surgery team, discusses probiotics, a “buzz word” in the food industry.

Beneficial Bacteria

Probiotics are “good” bacteria similar to organisms that occur naturally in the digestive tract. The digestive tract needs a healthy balance between good and bad bacteria for optimal health. Believe it or not, there are more than 100 trillion good bacteria living in the human body, many of which reside in the digestive tract. There are numerous strands of probiotics that have been linked to a variety of health benefits when administered in large enough amounts.

Why Take Probiotics

A study conducted at Stanford University School of Medicine examined the effect of probiotics in post-operative Roux-en-Y gastric bypass surgery patients. After three months, the participants who had taken a daily probiotic supplement had higher average weight loss and enhanced absorption of vitamin B12. In addition to these findings, probiotics, particularly lactobacillus acidophilus, may facilitate lactose digestion in lactose-intolerant individuals, a common problem for post bariatric patients.

Food Sources of Probiotics vs Supplements

Probiotics are found in cultured dairy foods such as yogurt and kefir. The number of active cultures found in foods varies greatly, depending on the type of bacteria and food processing. Certain processes to prolong shelf life, such as pasteurization in yogurt, can kill off some of these beneficial bacteria. Look for yogurts that have a “Live and Active Cultures” seal, as these contain approximately 22 million active cultures in a typical 8-oz serving. Additional food sources include pickled vegetables, sauerkraut and dark chocolate.

Supplements generally contain a much more concentrated supply of probiotics, providing 100 million to 1 trillion active cultures per dose. When shopping for probiotic supplements, look for one with many species of lactobacillus, such as L. acidophilus or bifidobacteria, as strains of these probiotics have been shown to improve digestion and have an extensive safety record for use in the generally healthy population. There is no specific dose recommendation and products should be used according to the manufacturers’ recommendations.