High-Protein Diets May be Key to Combating Obesity Epidemic

When the body breaks down protein-rich foods, the chemical phenylalanine is produced. In a new study, this chemical was found to trigger hormones that decreased the appetite of mice and led to weight loss.

The findings, presented at the Society for Endocrinology annual conference in Brighton, may help provide new ways for obesity treatment or prevention.

For the study, several experiments were conducted using both mice and rats. In the first experiment, researchers administered 10 rats and mice a single dose of phenylalanine. The second experiment involved diet-inducedobesemice that were given phenylalanine repeatedly over the course of 7 days.

The findings of both experiments were compared against the same number of rodents that did not receive phenylalanine.

The results of the study showed that the single-dose of phenylalanine reduced food intake, increased GLP-1 levels, and decreased levels of ghrelin. Ghrelin is a hormone that lets us know we are hungry, while high levels of the GLP-1 hormones indicate when we are full and should stop eating.

Additional findings showed that repeated administration of phenylalanine resulted in weight loss in the obese mice. The rats were found to be moving around more, which researchers said may encourage them to lose weight.

In order for researchers to fully understand the mechanisms of phenylalanine stimulating these hormones, a final experiment involving gut cells in a petri dish was conducted. The results of the final experiment revealed that phenylalanine interacted with the calcium sensing receptor (CaSR), which caused levels of GLP-1 to increase and appetite to decrease.

“Our work is the first to demonstrate that activating CaSR can suppress appetite,” said lead study author Mariana Norton. “It highlights the potential use of phenylalanine or other molecules which stimulate CaSR — like drugs or food components – to prevent or treat obesity.”

The authors noted that more research needs to be done on the precise mechanisms by which phenylalanine suppresses appetite and body weight. Furthermore, it’s likely that there are additional mechanisms involved.

For the next step in the process, researchers will try to determine whether phenylalanine can produce the same effects in humans that were seen in mice. Additionally, they hope to further confirm the importance of CaSR.