In 2002 they found that the arteries in these mice never clogged up, no matter how much fat they ate, an indication that a lack of leukotrienes lowered the inflammation risk behind atherosclerosis.

FORBES: Health

While men ate the same amount of fat no matter how much sleep they got, the women averaged 31 more grams of fat after sleeping for four hours.

CNN: Sleep deprivation spurs hunger

But spotting those mothers whose bumps are due to fat as well as baby is difficult, not least because there are no UK guidelines on how much weight women should gain during pregnancy.

BBC: Fat, pregnant or both?