Scientists Combat Mild Obesity by Freezing Hunger-Signaling Nerve

When it comes to dropping some pounds, people have hundreds of options. There are trendy diets and diet beverages; there are fitness trackers and 3D-printed glasses that count calories. Unfortunately, the majority of these methods don’t work. The most effective way to lose weight, a team of scientists announced Thursday, may be a little more extreme: Inserting a needle through a person’s back and freezing the nerve that carries hunger signals to the brain.

While the idea may make you squeamish, the scientists behind this new research reassured audiences at a presentation at the Society of Interventional Radiology’s 2018 Annual Scientific Meeting that the method is safe and feasible. Designed to help people with mild to moderate obesity, the researchers announced in a statement released Thursday that their weird intervention is an effort to “help people succeed with their own attempts to lose weight.”

“Medical literature shows that the vast majority of weight-loss programs fail, especially when people attempt to reduce their food intake,” study lead author and Emory University interventional radiologist Dr. David Prologo explained in the statement.

“When our stomachs are empty, the body senses this and switches to food-seeking survival mode. We’re not trying to eliminate this biological response, only reduce the strength of this signal to the brain to provide a new, sustainable solution to the difficult problem of treating mild obesity.”

Their initial pilot study focused on 10 subjects with mild to moderate obesity, each with a Body Mass Index (BMI) between 30 and 37; according to the World Health Organization, having a BMI 30 or higher puts you within the obese range. Obesity is then divided into three classes varying in severity, with BMIs ranging from 30 to 34.9, 35 to 39, and then 40 and above.

Each of the participants underwent a procedure in which a needle was inserted through their back and, guided by live images from a CT scan, an interventional radiologist used argon gas to freeze a nerve located at the base of the esophagus. This nerve is called the posterior vagal trunk and is one of the ways the brain is alerted that the stomach is empty and ready to chow down.

The technical success rate for the procedure was 100 percent: By freezing the nerve, the scientists reduced the strength of the signals it sends to the brain. When checked on 90 days later, all the patients reported a decreased appetite: 17 percent said they had “somewhat less appetite,” 30 percent had “much less appetite,” and 53 percent reported “very much less appetite.” On average, the participants lost about 3.6 percent of their initial body weight. Freezing the posterior vagal trunk, it turned out, was a lot more effective than counting calories or a Fitbit.

This biological hack stands a chance at being a breakthrough for those with the odds stacked against them. In January, a team of European researchers announced that it’s extremely difficult for obese people to lose weight because fat can become inflamed, scar, and become a permanent part of the body. This makes weight loss very difficult.

Because this new study only involved 10 people, the scientists now want to recruit more patients for a larger trial in order to tess the procedure’s efficacy and durability. Obesity induces 18 percent of deaths in the United States — meaning that this new method isn’t an exercise in vanity but rather life-saving health.