What a woman eats around the time she conceives can influence whether she has a boy or a girl, British researchers said today.
Experts said they had uncovered the first direct evidence that food intake is linked to a baby’s gender.
Women who consume a lot of calories when trying for a baby are more likely to give birth to a son, they said.
Women who ate around 2,200 calories a day were 1.5 times more likely to have a boy than those who ate less than 1,850 calories a day.
The eating of breakfast cereals before and around the time of conception was also “strongly associated” with women producing sons, the researchers said. They worked out that women eating breakfast cereals were 1.89 times more likely to have a boy than those who did not consume them.
Diets high in a number of nutrients, including potassium, calcium and vitamins C, E and B12, were also linked to male births.
The study was led by experts from the University of Exeter and the University of Oxford.
The research focused on 740 first-time pregnant mothers in the UK, who did not know the sex of their foetus. The results showed a link between food intake and gender around the time of preconception but not at other times in pregnancy.
Lead author, Dr Fiona Mathews, from the University of Exeter, said: “I think if you are wanting to conceive a boy then the breakfast-cereal finding is the main thing that popped out. Women who had boys also had a 300mg higher daily intake of potassium so foods like bananas are good.”
Dr Mathews said it did not seem to matter which food groups those consuming 2,200 calories a day relied on. “It does not seem to matter whether you get most of your energy from carbs or fat, it’s about the total amount of calories consumed,” she said.
The researchers said that over the last 40 years, there has been a small “but highly consistent” decline in the proportion of boys born in industrialised countries. Changes in the diets of young women may explain the pattern, they added.
Dr Mathews said: “This research may help to explain why in developed countries, where many young women choose to have low calorie diets, the proportion of boys born is falling."
PA