Wed, Apr 22, 2008 (HealthDay) — What a woman eats at about the time of conception could influence whether her baby is a boy or girl, British researchers say.

The study by the Universities of Exeter and Oxford found that a high-calorie diet, including regular breakfasts, could raise a woman's odds of having a boy, BBC News reported.

The trend toward low-calorie diets in developed nations could explain why the ratio of boys to girls is shifting in those countries, the network said.

In studying 740 first-time pregnancies, the researchers found 56 percent of women with high-calorie diets at the time of conception had boys, compared to 45 percent of women who had low-calorie diets. Women who had sons also were more likely to consume nutrients including potassium, calcium, and vitamins C, E, and B12, the researchers said.

The study was published in the journal Biological Sciences.