Pudgy older fathers live longer, are more attractive to the opposite sex and are better at passing on their genes than their leaner counterparts, scientists have claimed.

科学家表示，年长体胖的男性比偏瘦的男同胞更长寿，更吸引异性，生育能力也更强。

Becoming fatter after fatherhood due to decreasing testosterone levels may not fit the "macho" ideal, but it actually prolongs lives and strengthens immune systems, according to Richard Bribiescas, professor of anthropology and deputy provost at Yale University.

There is evidence that these men are less likely to suffer from heart attacks and prostate cancer, while a study in 2008 found that men with high metabolisms were around 50 per cent more likely to die in a given year than those whose bodies burned up less energy at rest.

"Macho makes you sick," said Prof Bribiescas. "The Hollywood image of the swaggering, dashing man dispatching bad guys and carrying the day conjures up a perception of indestructibility.

"While men are on average larger and physically stronger than women, men have a considerable weakness.

"We have a harder time fighting off infections and illness compared with women, and...men simply do not take care of themselves.

Prof Bribiescas also argues that becoming more podgy makes dads more likely to invest their time in their children rather than looking for other women, while the increased levels of fat could make them more attractive to women.