If you’ve ever lost weight only to watch the pounds creep back on, you’re not alone. Now, scientists have uncovered a biological explanation for this frustrating phenomenon known as the “yo-yo effect” – and it turns out our fat cells have a surprisingly long memory.
Researchers at ETH Zurich have discovered that being overweight leaves a lasting imprint on our fat cells through a process called epigenetics – chemical markers that act like tiny switches controlling which genes are turned on or off in our cells. These markers can persist for years, making it easier for the body to regain weight even after successful dieting.
“The fat cells remember the overweight state and can return to this state more easily,” explains Professor Ferdinand von Meyenn, who led the study published in Nature.
To reach this conclusion, the research team first studied mice, examining fat cells from both overweight mice and those that had successfully lost weight through dieting. They found that obesity created distinctive epigenetic “stamps” on the fat cells that stubbornly remained even after weight loss. When these mice were later given access to high-fat foods, they regained weight more quickly than mice without these cellular memories.
The findings weren’t limited to mice. The team also analyzed fat tissue samples from formerly overweight people who had undergone weight loss surgery, using samples from medical centers in Sweden and Germany. While they looked at different cellular markers in the human samples, the results aligned with their mouse studies, suggesting that human fat cells also “remember” their previous size. Perhaps most striking is how long this cellular memory might last.
“Fat cells are long-lived cells. On average, they live for ten years before our body replaces them with new cells,” says Laura Hinte, a doctoral student involved in the research.
Currently, there’s no way to erase these cellular memories with medication, though that could change in the future. For now, the researchers emphasize that prevention is key, particularly for young people.
“It’s precisely because of this memory effect that it’s so important to avoid being overweight in the first place. Because that’s the simplest way to combat the yo-yo phenomenon,” von Meyenn notes.
The team is now investigating whether other types of cells, such as those in the brain or blood vessels, might also harbor memories of previous weight gain. If so, this could help explain why maintaining weight loss is such a complex challenge for so many people.
This breakthrough research not only helps explain a frustrating aspect of weight loss that millions have experienced but also underscores the importance of preventing weight gain in the first place – our cells, it seems, never quite forget.
Source : https://studyfinds.org/fat-cells-remember-being-fat/