IT was already known that men find curvy women more attractive and that they live longer. Now research suggests that women with an hourglass figure are brighter and have cleverer children, too.

The study found that women with large hips and small waists are more intelligent than those with either “apple-shaped” or linear bodies.

The paper, to be published in the journal Evolution and Human Behaviour this week, suggests that such women give birth to more intelligent children - possibly a result of higher levels of omega3 fatty acids on the hips.

The researchers believe that the results offer a new explanation for why many men find curvy women more alluring. Nigella Lawson, the cookery presenter and Oxford University graduate, has one of Britain’s most famous hourglass figures, while Rachel Weisz, the curvy actress who won an Oscar for her role in The Constant Gardener, completed an English degree at Cambridge University while embarking on the first stages of her acting career.

In the research, scientists at the Universities of Pittsburgh and California, Santa Barbara, used data from a study of 16,000 women and girls, which collected details of their body measurements and their scores in cognitive tests. They found that those women with a greater difference between the waist and hips scored significantly higher on the tests, as did their children.

Such women are not necessarily skinny. What is important is that their waist should be smaller than their hips, with the ideal ratio being between 0.6 and 0.7.

The researchers suggest that the fat around fuller hips and thighs holds higher levels of omega3 fatty acids which are essential for the growth of the brain during pregnancy. Fat around the waist may have higher levels of omega6 fatty acids, which are less suited to brain growth.

Waist fat can also be a contributory factor in diabetes and heart disease. Thinner or linear-shaped women would simply lack enough of either type of fat.

Although these theories await confirmation, Paula Hall, a sexual and relationship psychologist with Relate, said: “Having research that proves you can be sexy and intelligent is really positive. It shows that curvy women may be better at things other than raising children and doing cooking and housework.”

The research may also explain why children born to teenage mothers do worse in cognitive tests: their mothers may have had insufficient stores of the best fatty acids.

“The cognitive development of their children is reduced, and their own cognitive development is impaired compared with those mothers with a later first birth,” say the researchers.

The study noted, however, that children born to teenage girls with traditional hourglass figures seemed to be protected from this phenomenon and did better in tests.

A number of scientific studies have shown that men are “hard-wired” to find women with a greater waist-hip differential the most attractive. No one has yet been able to explain this, although theories include enhanced fertility, better childbearing abilities and longer life expectancy.

Dr Harry Witchel, a senior lecturer in physiology at the Brighton and Sussex Medical School and a body language expert on the television programme Big Brother, said: “Until this point the only thing we have accepted is that they [curvy women] are at an advantage in contemporary western society. What these people are saying is that they also have an advantage biologically.”

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