Want a Boy? Eat Your Wheaties!

New research suggests that what a woman eats before pregnancy influences the gender of her baby.

Having a hearty appetite, eating potassium-rich foods, including bananas, and not skipping breakfast seemed to raise the odds of having a boy.

The British research is billed as the first in humans to show a link between a woman's diet and whether she has a boy or girl.

It is not proof, but it fits with evidence from test-tube fertilization that male embryos thrive best with longer exposure to nutrient-rich lab cultures, said Dr. Tarun Jain. He is a fertility specialist at University of Illinois, Chicago, who wasn't involved in the study.

It might be that it takes more nutrients to build boys than girls, he said.

University of Exeter researcher Fiona Mathews, the study's lead author, said the findings also fit with fertility research showing that male embryos aren't likely to survive in lab cultures with low sugar levels. Skipping meals can result in low blood-sugar levels.

Jain said he was skeptical when he first heard about the research. But he said the study was well-done and merits follow-up to see if the theory proves true.

While sperm determine a baby's gender, it could be that certain nutrients or eating patterns make women's bodies more hospitable to sperm carrying the male chromosome, Jain said.
The study was published Wednesday in the Proceedings of the Royal Society B, a British medical journal.

The research involved about 700 first-time pregnant women in the United Kingdom who didn't know the sex of their fetuses. They were asked about their eating habits in the year before getting pregnant.

Among women with the highest calorie intake before pregnancy (but still within a normal range), 56 percent had boys versus 45 percent of the women with the lowest calorie intake.

Women who ate at least one bowl of breakfast cereal daily were 87 percent more likely to have boys than those who ate no more than one bowlful a week.

In the study, eating very little cereal was considered a possible sign of skipping breakfast, Mathews said.

Compared with the women who had girls, those who had boys ate an additional 300 milligrams of potassium daily on average, "which links quite nicely with the old wives' tale that if you eat bananas, you'll have a boy," Mathews said.

Women who had boys also ate about 400 calories more daily than those who had girls, on average, she said.

Dr. Michael Lu, an associate professor of obstetrics, gynecology and public health at the University of California, Los Angeles, said the results "are certainly plausible from an evolutionary biology perspective." In other words, since boys tend to be bigger, it would make sense that it would take more calories to create them, Lu said.