Meal timings could prove to be helpful in promoting fertility among women suffering from polycystic ovarian syndrome by impacting menstruation, hormones and ovulation, a new study revealed.
Women with the disorder are typically "insulin resistant" - their bodies produce an overabundance of insulin to deliver glucose from the blood into the muscles.
The excess makes its way to the ovaries, where it stimulates the production of testosterone, thereby impairing fertility.
The goal of Daniela Jakubowicz of Tel Aviv University's Sackler Faculty of Medicine and the Diabetes Unit at Wolfson Medical Center, maintenance meal plan, based on the body's 24 hour metabolic cycle, is not weight loss but insulin management.
Women suffering with PCOS who increased their calorie intake at breakfast, including high protein and carbohydrate content, and reduced their calorie intake through the rest of the day, saw a reduction in insulin resistance.
Jakubowicz observed that this led to lower levels of testosterone and dramatic increase in the ovulation frequency - measures having a direct impact on fertility.
Many of the treatment options for PCOS are exclusively for obese women, Prof. Jakubowicz explains. Doctors often suggest weight loss to manage insulin levels, or prescribe medications that are used to improve the insulin levels of overweight patients. But many women who suffer from PCOS maintain a normal weight - and they are looking for ways to improve their chances of conceiving and giving birth to a healthy baby.
In a recent study, Prof. Jakubowicz and her fellow researchers confirmed that a low-calorie weight-loss plan focusing on larger breakfasts and smaller dinners also lowers insulin, glucose, and triglycerides levels.
This finding inspired them to test whether a similar meal plan could be an effective therapeutic option for women with PCOS.
Sixty women suffering from PCOS with a normal body mass index (BMI) were randomly assigned to one of two 1,800 calorie maintenance diets with identical foods. The first group ate a 983 calorie breakfast, a 645 calorie lunch, and a 190 calorie dinner.
The second group had a 190 calorie breakfast, a 645 calorie lunch, and 983 calorie dinner. After 90 days, the researchers tested participants in each group for insulin, glucose, and testosterone levels as well as ovulation and menstruation.
As expected, neither group experienced a change in BMI, but other measures differed dramatically. While participants in the "big dinner" group maintained consistently high levels of insulin and testosterone throughout the study, those in the "big breakfast" group experienced a 56 percent decrease in insulin resistance and a 50 percent decrease in testosterone.
This reduction of insulin and testosterone levels led to a 50 percent rise in ovulation rate, indicated by a rise in progesterone, by the end of the study.
The research has been published in Clinical Science.