Stress Loses Weight On Weight Gain
Despite a long-time belief that stress equals weight gain, by causing people to reach for comfort foods or skimp on exercise, a new research found that stress does not have a long-term effect on weight.
The results are surprising, say researchers, given the common notion that stress plays a big role in weight gain.
When researchers looked into 32 previously published studies on the issue, however, they found that most of the cases showed no association between stress levels and weight gain over several years.
The team found that when all the data was put together from all the studies’ results, there was only a modest association overall between stress and weight gain.
“When we started this meta-analysis, we assumed that there would be a substantial association between stress and obesity, since the popular view is that stress contributes to weight gain,” co-researcher Dr. Andrew Steptoe, of University College London in the UK, told Reuters Health in an e-mail.
“But when we looked carefully at well-controlled scientific studies, effects were surprisingly small,” he said.
The findings does not necessarily mean that stress cannot have a significant impact on some people’s weight, says Steptoe. The effect of stress on weight may be small in a wide basis, but there could be many variations among individuals, he added.
For example, Steptoe noted that “some people may increase their food consumption under stress,” while others may lose their appetite and eat less.
He also said that different types of stress might have different effects on weight gain.
For the study, the team, led by Dr. Jane Wardle, also of University College London, analyzed 32 studies conducted internationally in the 1990s and 2000s.
All of the analyzed studies assessed participants’ stress levels, then followed them over time to see whether there was a link between stress and weight gain. Participants were followed for one to seven years in most studies, however, a few studies followed subjects for as long as 38 years.
Some of the studies focused on work-related stress, while others focused more on general life stress, which includes anything from major traumas like divorce or illness, to feeling overwhelmed with daily tasks and hassles.
The team discovered that 69 percent of the studies found no clear association between stress and weight gain. About 25 percent of the studies linked higher-stress levels to greater weight gain, and the remaining 6 percent found that greater stress was related to less weight gain over time.
When researchers combined results from all of the studies, they found a modest relationship between higher stress levels and greater weight gain.
The team also found a stronger connection between stress and weight gain among men than among women, according to Steptoe, who added that it’s a “popular belief” that stress has a greater impact on women’s weight.
“Based on the current scientific research, stress is not likely to play a major role in increasing body weight or obesity for most people,” said Steptoe.
“It could be that some people are more affected than others, but rather little is known about this at present,” he added.
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