Breakfasting on Shredded Wheat or cornflakes has been found to increase dramatically a woman’s chances of having sons instead of daughters. Up to 59 per cent of women who get pregnant after eating high-energy breakfasts end up giving birth to a son.

By contrast, researchers have found, only 43 per cent of women who always skipped breakfast before conceiving managed to produce boys.

When food consumption is considered across the whole day the pattern is repeated, with 56 per cent of women eating high-energy food having sons. Of the women on low-energy diets, only 45 per cent had boys.

The findings, the first direct evidence that what is on the menu can influence gender, suggest that preoccupation with dieting is increasing the proportion of baby girls.

Scientists said that the discovery of a link between calories and gender may explain why it is that in the past 40 years there has been a small but steady decline in the proportion of boys born in the developed world.

Fiona Mathews, of the University of Exeter, said eating high-calorie breakfasts seemed to be the best guarantee of influencing the gender of a baby in favour of boys before conception. Getting into the routine of eating breakfast cereals seemed to be more influential than which brand was consumed, she said.

“Those women who eat the most are the ones who are most likely to have male babies,” she said. “Cereals seem to be one of the key food groups.”

Teams from Exeter and Oxford universities studied consumption patterns of 740 women. All of the women were pregnant but were unaware of the gender of their foetus when they were asked to supply details of what they ate in the weeks before and after conception. The quantity and range of nutrients consumed, including potassium, vitamins C, E and B12, and calcium, were also found to influence gender in favour of male births.

The weight of the women was ruled out as a factor and the researchers, who pointed out that average energy intake in the industrialised world has fallen in recent years, held that obesity was more attributable to lack of exercise and food quality than the amount consumed. Gender is determined genetically by the father’s sperm but mothers appear to be able to influence the gender of their babies.

Scientists remain unclear of the mechanism but IVF researchers have found that high levels of glucose enhance the growth and development of male embryos at the expense of female embryos.

The Exeter and Oxford team noted that skipping breakfast had the effect of lowering glucose levels, which the body, in a hangover from mankind’s hunter-gatherer roots, may interpret as being a sign that food is in short supply. A link between food availability and gender has been identified previously in animals.

“If a mother has plentiful resources then it can make sense to invest in producing a male because he is likely to produce more grandchildren than a female,” Dr Mathews said.

The researchers, publishing their findings in the journal Proceedings of the Royal Society B: Biological Sciences, said it was likely that similar evolutionary forces were at work for humans.

Old mothers’ tales

— The mother-to-be must pick up a single key. If she lifts it up by the handle her child will be a boy, by the other end, a girl, and by the middle, she will have twins

— A wooden spoon or pair of scissors placed under the bed, or a pink bow under your pillow, will result in a girl

— Eat only the ends of loaves of bread for a boy. For a girl, eat only the middles

— Eating salty foods, meat and cheese is supposed to produce a boy. Eating sweet food and fruit is said to result in a girl

Sources: storknet.com; thelabouroflove.com

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