Here is an interesting article from Scientific American that quite nicely explains this phenomenon. Yes we have gone through all this before in other articles on this site but I have heard that someone needs to hear something 7 times before it really sinks in.

Fat deposits in men and women differ for obvious biological reasons. The fat stores on women at the buttocks and thighs are emergency supplies for her unborn offspring in case of famine. Its an emergency energy stockpile to provide energy to the baby when the mother has no access  to food. This genetic programing allowed humans to procreate and pass on the genes to avoid extinction during times of famine.

Any woman who has tried losing this stubborn fat can attest to how difficult it is to get it off. Once again we have a prehistoric program running in our advanced brains in an ultra modern age. Food shortages are hardly a problem any more.

Men tend to store fat in their bellies. It is usually stored under that layer of muscles which is why pot bellies are rock hard and not flabby like other fat deposit areas. Men should learn about the extreme dangers of this belly fat. It has a tremendous negative effect on health. Any man who has a waistline of more than 35 inches, should seriously consider shedding some of the unwanted pounds.

Well anyway, here is the article from Scientific American.