It may sound like the start of some unkind joke but according to a study carried out by the scientists at Pittsburgh University in Pennsylvania, mums with bigger bums have cleverer kids. So if you are planning to have a baby and spend hours agonising over the size of your derriere, the good news is that the stress is over – the size of your bum is good for your baby
Fat = brain cells
According to Will Lassek, a public health epidemiologist at the university and the lead researcher, the fat contained within the bum is a kind of storage depot for the materials needed to develop a baby’s brain. This is because plenty of fat is needed to create the nervous system in the foetus and the fats in the area of the bum are also enriched in a substance called docosahexaenoic acid or DHA. This stuff is crucial to the brain because it is one of the main components used to make it.
So this necessary storage of materials could be in part the reason that women have more sizeable bums than men – they are storing up this useful material in anticipation of needing to pass it on to their babies. In fact, it helps explain why women have more fat in general than men – around 30% in total. It seems that these fats are then mobilised during pregnancy and sent through to the foetus to help it develop, particularly with brain.
Professor Lassek added that this is similar to the levels seen when bears hibernate or when whales are living in the cold seas of the Arctic. The fat is used to store useful substances that are needed at different points in life for different tasks. This explains in part why some women find it difficult to rid themselves of fat in these areas – their bodies are holding on to it in preparation for having children and needing to pass it on to them.
Muscle to fat
In fact, as women have evolved they have traded their muscle for fat, meaning they are only around one third as strong as men. A man’s body is composed of around 5-10% fat and have a more linear shape. This shape also means this is why it is much easier for a man to lose weight that it is for a woman. Fat naturally heads to the belly area on men while on women it tends to go to the bottom and thighs and is much harder to move.
Professor Lassek added that women lose quite an amount of extra fat during the breast feeding period when it is needed for the baby’s brains. Breast feeding women can lose around one pound of fat a month. And the majority of this fat comes from the thighs and buttocks where helpful fatty acids are stored needed by the brain to develop.
In fact, over the last five million years, the human brain has grown by around three times in its average size from 400ml to 1200ml. Therefore, the corresponding increase in the fat on women could well be to help create this larger brain requirement.
David Bainbridge, biologist from Cambridge University, is another who has studied women’s body shape and says these finding help to explain why men find curvy women such as singer Jennifer Lopez so attractive – their instincts are telling him their children with these women are likely to be clever!
He said that in his studies he has seen that the brain building breast milk lipids or fats are found mainly in the fat stored in the thighs and buttocks. Women that have larger levels of these have larger thighs and he too believes there is a connection with the intelligence of these women’s children.
A study in June last year also backed this theory, showing that men preferred curvier women. The lead author, Dr Viren Swami of the University of Westminster believes that men’s survival instinct has come into force with this voice. In that little voice of instinct, someone who is heavier has access to food and our minds tell us being with that person is likely to benefit it.
Another study conducted by St Andrews University in Scotland concluded that men were drawn to curvier women because they appeared more healthy than their thinner counterparts.
It has been theorised that women with the body type that sees them carry weight below the waist also have a lower level of cholesterol and are more likely to produce the hormones that are needed to metabolise sugar. The results of this means they are less at risk of developing diabetes, high cholesterol levels and heart disease.
Another connection between fat and intelligence comes through a substance we hear mentioned a lot – Omega 3, the fatty acid always tagged as a ‘good fat’. A 2010 study from the University of Oxford connected the fat reserves on the body with intelligence through this substance as it also has a big part to play in the development of the brain.
And prior to that in 2007, the Chicago Tribune published details of a study that showed fat bottomed women were more intelligent than those with flat bottoms because the extra fat had a high amount of Omega 3 in it and this improved the efficiency of the brain.
Unfortunately all this good news doesn’t mean that a fat bottomed lady need not worry about what she eats or getting exercise. On the contrary, even with the natural benefits of the hour glass shape, a lady still need to stay active and watch what she eats because health related illnesses can still strike.
The good news for those who have a more slender behind is that all is not lost for their children’s intelligence – other studies have shown that fish oil and vitamin D can both help boost brain development while singing to a baby is also beneficial, even if you can’t really sing!