Many people who struggle with their weight know the problem of yo-yo dieting. Yo-yo dieting is the act of constantly losing and gaining weight. Many of us blame willpower or our habits for the cycle. But there is also a biological reason for it.
“We’ve found a molecular basis for the yo-yo effect,” said Ferdinand von Meyenn, professor of nutrition and metabolic epigenetics at ETH Zurich Univ.
According to Prof. von Meyenn’s research, obesity causes genetic changes within fat cells, creating stored “memories” of being overweight in their nucleus. Those memories make it easier for the body to regain weight later.
The team first saw the changes in mice. The cell changes happened in obese mice but remained after the mice lost the weight through diet. The team confirmed their find in humans by looking at fat samples from people who had lost weight via gastric bypass procedures.
It’s unknown how long cells can “remember” things. They may forget the memory or be prone to weight gain for as long as they exist. “Fat cells are long-lived cells. On average, they live for 10 years before our body replaces them with new cells,” said Dr. Laura Hinte of Prof. von Meyenn’s group.
Currently, no medications change “memories” within the cell nucleus. Cells that have been fat in the past want to return to that state. They respond faster to sugars and fatty acids than cells that were never fat. But, as of now, there is no way to reverse that.
People might have to wait out the ten years with careful diet and exercise. “It’s possible that maintaining a reduced or healthy body weight for long enough is enough to erase the memory,” said Dr. Hinte.
The fat cells aren’t being malicious. They don’t know that they are undermining our dieting efforts. They are doing their job. “From an evolutionary perspective, this makes sense,” said Dr. Hinte. “Humans and other animals have adapted to defend their body weight rather than lose it, as food scarcity was historically a common challenge.”
If you struggle with yo-yo dieting, this study may help you understand your problem more. It’s not a lack of willpower or bad habits. There is a sizeable biological component. While overcoming the issue with a decade-long commitment seems possible, there is no easy fix. That can be disheartening to hear. However, taking small steps and working on your health one day at a time is essential!
