Could obesity eventually be treated with a probiotic?

One of the most interesting areas of medical research is the effect of different kinds of bowel bacteria on our health.

One intriguing piece of information is that people who are thin seem to have different types of bacteria in their bowels than people who are obese.

In animal models the bacteria species Bacteroides is associated with normal weight. In contrast having an abundance of the bacteria Firmicutes promotes obesity.

Is it possible that obesity may be treated, in part, with a probiotic containing Bacteroides?

In 1907 Metchnikoff, a Nobel Prize recipient, postulated that the bacteria in our bowels in some way contribute to our health. This idea did not really resonate until the 1980s when the term probiotic was coined to describe bacteria consumed as a dietary supplement for health benefits.

Since that time, research has been accumulating indicating that the types of bacteria in our bowels can have a substantial positive and negative impact on our health. Indeed some studies have shown that robust levels of the bacteria Bifidobacterium and Lactobacillus in the bowels may improve anxiety, depression and obsessive-compulsive disorders.

One recent clinical trial demonstrated that the symptoms of irritable bowel disease significantly improved with a probiotic containing several different species of bacteria. Of note, the benefits lasted only as long as the probiotic was being used and that finding is important.

Obesity is a medical condition that has reached epidemic proportions. The definitions of obesity vary somewhat, but being overweight increases the risk of almost all illness including at least 11 different cancers. It is the most preventable cause of premature death in the United States.

Severely obese individuals are three times more likely to die than those who are normal sized. Although there may be some genetic reasons predisposing, lifestyle is the main reason.

Interestingly, in animal models, the kind of bacteria in the bowels may increase or decrease the risk of obesity.

I came across an article in the medical journal Postgraduate Medicine (2015) demonstrating that high levels of Firmicutes in the bowels of mice predisposed them to obesity. Bacteroides did the opposite.

Adding Firmicutes to lean mice resulted in obese mice and giving obese mice Bacteroides tended to lean them out.

The same was tried in humans without success. Sadly the conclusion was that the quality of gut bacteria does not affect obesity.

However, I feel that the conclusion was wrong.

Laboratory mice are fed a specific diet and there are not many midnight trips to the local pizza place for them. Humans have a varied diet and this variation in diet affects the bacteria in the bowel even after supplementation with a probiotic.

Some web sites claim that probiotics can result in weight loss, that they are a magic pill eliminating any personal effort.

Probiotics are not a magic pill.

They may be an important adjunct to diet, stress reduction and exercise in treating obesity.

Before the weight-loss benefits of a Bacteroides-based probiotic can be realized, in humans, other lifestyle changes must be made.

• Patrick B. Massey, MD, PH.D., is medical director for complementary and alternative medicine at Alexian Brothers Hospital Network and president of ALT-MED Medical and Physical Therapy, 1544 Nerge Road, Elk Grove Village. His website is www.alt-med.org.