The researchers, from Oxford and Exeter universities, found that women with the highest calorie intake before conception were more likely to have a boy than women on a low calorie diet.
The latest research, published in the Royal Society journal Biological Sciences, looked at 740 first-time mothers in Britain and asked about their eating patterns in the year before they conceived.
They then divided the women into high, medium and low calorie groups. The study revealed that 56 per cent of women who ate more than 2,200 calories a day before conception had a boy, compared with 45 per cent of women who ate less than 1,850 calories.
Fifty-nine per cent of women who had cereal every day conceived a son, compared with 43 per cent of those who had less than one bowl a week. Women with sons also had higher levels of nutrients in their diets, such as potassium, calcium and vitamins C, E and B12, the researchers found.
There has been a decline in the proportion of boys being born in western countries for the past 40 year, according to BBC News. It is a drop of about one per 1,000 births annually. The researchers said the results suggested that the dieting habits of women in the western world could help explain the falling male birth rate.
Nutritional data was collected for three time periods: usual intake before conception, intake at around 16 weeks' gestation, and usual intake between 16 and 28 weeks' gestation.
Skipping or eating low calorie breakfast decreases glucose levels in the body, which is regarded by the body as indicating poor conditions and low food availability. The new study found that having a boy was also linked to higher levels of potassium.
