It is well known that sex is determined by X or Y chromosome. But, a mother with poor-nutrition diet brings more girls, because the male embryo can’t sustain or develop in harsh environment. To have a boy, a mother should prefer high-energy intake with high level of glucose and well-balanced nutrition, which doesn’t mean the more calories the better. A higher quantity and wider range of nutrients, including potassium, calcium and vitamins C, E and B12 will benefit women hoping for a son.