Here Comes the Exercise Pill

Researchers at Baylor College of Medicine, Stanford School of Medicine, and collaborating institutions have identified a molecule in the blood that is produced during exercise. It can effectively reduce food intake and obesity in laboratory mice.

"We wanted to understand how exercise works at the molecular level to be able to capture some of its benefits," says researcher Jonathan Long in a press release issued by Baylor College of Medicine. "For example, older or frail people who cannot exercise enough, may one day benefit from taking a medication that can help slow down osteoporosis, heart disease or other conditions."

A paper is published in Nature. It reports that exercise stimulates the production of a molecule called Lac-Phe. Conversely, a high dose of Lac-Phe, administered to fat mice, suppressed food intake by about 50% compared to control mice over a period of 12 hours, without affecting their movement or energy expenditure.

Lac-Phe is a modified amino acid synthesized from lactate and phenylalanine. Lactate is a byproduct of strenuous exercise that is responsible for the burning sensation in muscles. And phenylalanine is an amino acid that is one of the building blocks of proteins.

“In diet-induced obese mice, pharmacological-mediated increases in Lac-Phe reduces food intake without affecting movement or energy expenditure,” reads the paper. “Chronic administration of Lac-Phe decreases adiposity and body weight and improves glucose homeostasis. Conversely, genetic ablation of Lac-Phe biosynthesis in mice increases food intake and obesity following exercise training.”

The researchers also found that an enzyme called CNDP2, that is involved in the production of Lac-Phe, plays an important role. Mice lacking this enzyme did not lose as much weight on an exercise regime as a control group on the same exercise plan.

The findings improve our understanding of the physiological processes that underlie the interplay between exercise and hunger. In humans, sprint exercise, resistance training, and endurance training have been found to increase Lac-Phe. The researchers suggest that Lac-Phe regulates feeding and is associated with physical activity in many animal species.

"Our next steps include finding more details about how Lac-Phe mediates its effects in the body, including the brain," says researcher Yong Xu. "Our goal is to learn to modulate this exercise pathway for therapeutic interventions."

"Regular exercise has been proven to help weight loss, regulate appetite and improve the metabolic profile, especially for people who are overweight and obese," concludes Xu. "If we can understand the mechanism by which exercise triggers these benefits, then we are closer to helping many people improve their health."

Weight loss pills, their repercussions, and this new finding are discussed in a Hackernoon podcast. “We may be on the brink of having a miracle pill to turn us all into skinny legends without having to sweat so much!” However, the idea “isn't to take exercise off the table but to benefit people who are physically unable to exercise adequately.”