It is something that many of us have suspected for a long time. And now scientists have confirmed that sitting around really does cause a fat backside.
The more we sit down, the more fat cells in the buttocks expand creating a rounder derriere.
Scientists at Tel Aviv University revealed that ‘cellular expansion’ plays a key role in fat production because the pressure on cells causes them to increase in size by 50 per cent. They analysed the accumulation of fat cells in the body and found that nutrition only plays a small role in keeping slim.
Professor Amit Gefen, from the Department of Biomedical Engineering said: ‘We wanted to find out why a sedentary lifestyle results in obesity, other than making time to eat more hamburgers. ‘We found that fat cells exposed to sustained, chronic pressure – such as what happens to the buttocks when you’re sitting down – experienced accelerated growth of lipid droplets, which are molecules that carry fats.
‘Contrary to muscle and bone tissue, which get mechanically weaker with disuse, fat depots in fat cells expanded when they experienced sustained loading by as much as 50 per cent. This was a substantial discovery.’
The study, published in the Biophysical Journal, revealed that fat cells change in structure under pressure and are likely to expand, leading to weight gain.
‘When they gain mass and change their composition, expanding cells deform neighboring cells, forcing them to differentiate and expand,’ said Professor Gefen.
‘This proves that you’re not just what you eat. You’re also what you feel – and what you’re feeling is the pressure of increased weight and the sustained loading in the tissues of the buttocks of the couch potato.’
He added: ‘If we understand the etiology, or causes, of getting fatter, of how cells in fat tissues synthesize nutritional components under a given mechanical loading environment, then we can think about different practical solutions to obesity.
‘If you can learn to control the mechanical environment of cells, you can then determine how to modulate the fat cells to produce less fat.’
It is hoped that the research could be a first step in finding new ways of treating people with weight problems in the future.