freelance journalist, print journalist, online journalist, copywriter, content editor, freelance editor, health and lifestyle, blogger Feeling fat/thin/just right is in your jeans (sorry, genes) | Christine Morgan - Journalist
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Here’s another story about how your genes affect your behaviour in more ways than you might think. This time, it’s all to do with how you feel about your weight. We all know people who are as thin as whippets but moan at every opportunity about how fat they are. Similarly there are people who, let’s say, aren’t built for skinny jeans but wear them all the same, proudly showing off the flesh spilling over the tops of their waistbands like molten lava. Some genuinely don’t care about the social pressures that drive our attitudes about body weight. Others, however, don’t recognise their weight isn’t as healthy as it could be.

You’d think that how we see ourselves – too fat, too thin, just right – is strongly influenced by our experience of life and our environment. But scientists from the University of Colorado Boulder in the US argue there’s a good chance it’s dictated by our genes too. And if you’re female, that chance is even greater.

In an analysis of data that sampled more than 20,000 people – including hundreds of twins – the researchers measured the heritability of subjective weight status. And somehow they came up with the estimate that perceived weight status is 0.47 heritable (where 0 indicates that genetics aren’t a contributing factor in any way and with 1 indicating they’re the only contributing factor).

But why on earth is any of this interesting or relevant? Good question. Health assessments are reliable estimates of how long you’re likely to live, right? Well apparently some studies have shown that self-health assessments are at least as accurate as those made by doctors.

“One’s own perception about his or her health is a gold standard measure – it predicts mortality better than anything else,” says Jason Boardman, one of the report’s authors. “But those who are less flexible in assessing their changing health over time may be less likely than others to make significant efforts to improve and maintain their health.”

So there you have it. Next time your skinny friend says she can’t afford to take on the extra calories in another cappuccino, don’t assume she’s fishing for a compliment about her bony-arsed frame; remember, it could be in her genes.