Timing of calorie intake could be as important as total calorie intake when it comes to overcoming reproductive problems. A new study published in Clinical Science suggests eating a relatively larger breakfast and smaller dinner can have a positive effect on fertility. Proper meal timing could have special benefits for women with polycystic ovarian syndrome (PCOS), which affects 6 – 10 percent of women of reproductive age.

Women with PCOS disrupts the menstrual cycle by causing an imbalance of female sex hormones. These women develop many small fluid-filled cysts in their ovaries. In addition to disrupting the menstrual cycle, PCOS also creates resistance to insulin that may result in an increase of the male sex hormones, androgens, including testosterone. PCOS may also lead to hair loss on the scalp but increases in body hair, acne, future diabetes, and fertility problems.

Prof. Oren Froy, director of the Nutrigenomics and Functional Foods Research Center at the Robert H. Smith Faculty of Agriculture, Food and Environment of the Hebrew University, carried out the experiment at Wolfson Medical Center. The researchers wanted to study how the timing of caloric intake affects insulin resistance in women with PCOS. Froy and his team studied 60 women with between the ages of 25 to 39 over a 12-week period; each of the women suffered from PCOS and had a low body mass index (BMI) measuring less than 23.

The researchers divided the women into two groups and allowed each group to consume 1,800 a day. Froy and his team directed one group of women to eat a large breakfast containing approximately 980 calories. The researchers asked the other group of women to consume most of their daily caloric intake in the evening. The scientists asked the women to keep detailed records of their eating habits each day.

Glucose and insulin levels dropped in women who at large breakfasts while the big dinner group showed no changes. Furthermore, testosterone levels dropped 50 percent in the big breakfast group and stayed the same in the other participants.

Prof. Froy said, "The research clearly demonstrates that indeed the amount of calories we consume daily is very important, but the timing as to when we consume them is even more important."

Source: Daniela Jakubowicz, et al. "Effects of caloric intake timing on insulin resistance and hyperandrogenism in lean women with polycystic ovary syndrome." Clinical Science (2013) 125, (423–432). Web. 10 Oct 2013.