Diets high in unsaturated fats, whole grains, vegetables, and fish have been associated with improved fertility in both women and men. While current evidence on the role of dairy, alcohol, and caffeine is inconsistent, saturated fats, and sugar have been associated with poorer fertility outcomes in women and men. Furthermore, women and men with obesity [body mass index (BMI) ≥ 30 kg/m2] have a higher risk of infertility. This risk is extended to women who are underweight [BMI <20 kg /m2]
Diet and BMI influence outcomes during clinical treatment for infertility.