Good news if you worry about having a big bum: it makes your kids clever!
Yep, if you agonise about your curvy hips, thighs and buttocks, then it's time to stop, because scientists say bottom fat is what makes children intelligent.
Professor Will Lassek, a public-health epidemiologist at Pittsburgh University, Pennsylvania, told the Sunday Times: "The fat in these areas is a depot for building a baby's brain.
"You need lots of fat to make a nervous system, and the fats in these areas are also enriched in DHA (docosahexaenoic acid), which is a particularly important component in the human brain.
"It looks as if women have evolved to accumulate these fats and hold on to them – until a baby arrives."
Get the cream cakes out: it's time to celebrate!
It has long been a mystery why women have so much more body fat than men – typically 30 per cent of their total weight and, according to the learned Prof, similar to the levels seen in bears going into hibernation!
Men's bodies are made up of just five to 10 per cent body fat, and they have a much more straight up and down shape as a result.
Professor Lassek, who has published his research in the book Why Women Need Fat, said women's extra fat is lost during breast-feeding, when it is needed for their baby's brain.
Mums who breastfeed typically lose one pound of fat (half a kilo) a month.
Over the past five million years, the average human brain has trebled in volume from 400ml to 1,200ml.
It could therefore follow that women have had to become fatter to keep up with the growing demands of babies' brains.
David Bainbridge, a reproductive biologist at Cambridge University who has also studied the female body shape, said the latest findings could explain why men find curvy women (think Kim Kardashian, Beyonce and Jennifer Lopez) so attractive: it's because their children are likely to be cleverer.
He said: "The brain-building, breast-milk lipids (fats) are largely derived from the fat stored in a mother's thighs and buttocks.
"Women with larger thighs have higher levels of these lipids. There is even evidence that they and their children are more intelligent as a result."
What do you make of this research?
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