British scientists, who had previously linked changes in sex ratios in developed countries to pollutants and synthetic chemicals, found that low-calorie diets and skipping breakfast at the time of conception makes women more likely to conceive a girl and that higher energy intake means males.

This is the first evidence that associates a child's sex with the mother's diet.
In recent years, there has been a decline of newly born males in developed countries. The decline has been small but consistent, of about one per 1,000 births annually.

The scientists explain that eating no breakfast may be interpreted by the body as low food availability, since it depresses levels of blood sugar. Although the exact mechanism is unclear, high levels of glucose encourage the growth and development of male embryos and inhibit the female ones.

The researchers studied 740 first-time pregnant mothers in Britain and found that 56 % of those with the highest energy intake had sons in comparison to 45 % in the lowest group.

This correlation could also be explained by evolutionary terms. “If a mother has plentiful resources then it can make sense to invest in producing a son because he is likely to produce more grandchildren than would a daughter. However, in leaner times having a daughter is a safer bet," said one of the researchers.

Finally we get some real information that helps us plan the family.