A diet rich in steak and other red meat might hinder a man's chances of conceiving a child, say Spanish researchers. According to their study published in the journal 'Fertility and Sterility', a healthy antioxidant-rich diet might be the key to sperm quality and motility. Men who eat a lot of fruit and vegetables, in particular peppers, spinach and citrus fruits, have higher quality and faster swimming sperm.

'A healthy diet is not only a good way of avoiding illness, but improves the quality of semen' said Professor Jaime Mendiola, the leading researcher.

'We saw that, among couples with fertility problems coming to the [fertility] clinics, men with good semen quality ate more vegetables and fruit, which means more vitamins, folic acid and fibre, and fewer proteins and fats.'

The study, undertaken at the University of Murcia in Spain, was prompted by the gradual decline in sperm counts across Europe in the last few decades. Male patients at two Spanish fertility clinics took part, and scientists concentrated on the possibility that exposure to contaminants in the workplace and diet might be reducing chances of successful conception.

They hypothesised that antioxidants could potentially improve sperm concentration and motility by reducing or slowing the oxidation of other molecules which harms sperm.

Sixty-one men with fertility problems were enrolled into the study, 30 of whom had problems specifically with sperm count. Interviews with the participants showed that those with good sperm quality ate significantly more fruit and vegetables than those whose diets were rich in meat and full-fat dairy products.

'People who eat more fruits and vegetables are ingesting more antioxidants, and this is the important point' said Professor Mendiola. In his next study, he will investigate whether there is a difference in sperm count between men who get their antioxidants via food or from vitamin supplements.