It’s an age-old problem for dieters: losing a few pounds and then gaining them back quickly.
But now experts have discovered that our fat tissue retains a “memory” of obesity that persists even after losing weight, which could increase the chances of regaining excess weight.
The findings could help explain the so-called “yo-yo” effect often seen when dieting, the researchers said.
The scientists analyzed cells taken from body adipose tissue in 18 people who were at a healthy body weight, as well as in 20 obese people before and after losing weight after bariatric surgery.
They found that adipose tissue showed changes in RNA sequences (molecules that carry instructions for making proteins) even after substantial weight loss.
The analyzes were carried out in lean, obese and formerly obese mice and revealed similar changes that appeared to be related to alterations in some metabolic processes: chemical reactions that convert food and drinks into energy.
These may contribute to rebound weight gain after dieting, the authors said.
The team at ETH Zurich, a university in Switzerland, concluded that addressing these changes in the future could improve long-term weight management.
Experts have discovered that our fat tissue retains a ‘memory’ of obesity that persists even after losing weight, which could increase the chances of regaining excess weight (file image)
Scientists analyzed cells taken from body adipose tissue in 18 people who had a healthy body weight, as well as 20 obese people before and after losing weight after bariatric surgery (file image)
In an article in Nature magazine they said: ‘Reducing body weight to improve metabolic health and related comorbidities is a major goal in the treatment of obesity.
‘However, maintaining weight loss is a considerable challenge, especially because the body appears to retain a…memory that defends against changes in body weight.
“These changes…contribute to the problematic ‘yo-yo’ effect often seen in diets.”
Although their study focused on obesity, it is possible that a similar type of cellular “memory” could also play a role in other contexts such as alcohol or nicotine addiction, they added.
A previous study found that yo-yo weight loss can still improve overall health.
Scientists at the University of Oxford found that people who struggle to maintain their long-term goal weight remain healthier than before they lost weight, even if they regain a few pounds.
The study of more than 50,000 obese people revealed that those who regained some weight after a diet regimen still had lower blood pressure and cholesterol than before losing weight.
And the findings offer reassurance that any form of weight loss is beneficial, even if there is some regression.