An End To Yo-Yo Effect? Blocking Certain Neural Pathways May Halt Weight Gain After Dieting

Most people, who take up weight loss programs, face a common challenge--they tend to lose and regain the lost the pounds cyclically.

Now, a new study has now found that blocking certain neural pathways may bring an end to this yo-yo effect of dieting.

Although the exact mechanism behind the yo-yo effect of weight gain during dieting was not known, scientists knew the arcuate nucleus (ARC) located in the hypothalamus of the brain played a key role in regulating food intake and weight gain.

"People have looked mainly at the short-term effects of dieting. We wanted to see what changes in the brain in the long-term," Henning Fenselau, a researcher who led the study at Max Planck Institute of Metabolism Research, said, Lokmat Times reported.

To understand the link between weight gain and dieting, the scientists evaluated how food restriction affected ARC neurons. They then found that a restricted diet, such as fasting, activated these neurons, which triggers increased feeding and weight gain.

For the study, the researchers used postmortem examination of the brains of mice, some of which had fasted for 16 hours. The mice that fasted had more activity in the paraventricular hypothalamic nucleus (PVH) compared to those that did not fast.

To understand how inhibiting PVH neurons reduce food intake in mice, they silenced these neurons in a group of mice and tracked their food consumption for 24 hours. The team found that the mice with inhibited PVH neurons ate around 33% less food, when compared to the control group. The group with silenced PVH neurons also regained less weight over the next seven days.

The researchers also found that once the control group mice regained weight lost from fasting, the enhanced signaling from PVH neurons returned to normal.

Based on the new findings, the researchers suggest modifying future weight loss therapies to dampen the signaling from PVH neurons to maintain weight loss. However, more research is required to understand the function of these neurons and the effects of blocking them.

Since the study is conducted on mice, further research is also required to evaluate the impact on humans.