“We’ve had one, yes. But what about second breakfast?” Pippin replied to Aragorn in The Lord of the Rings: The Fellowship of the Rings (2001). How would a hobbit manage with one breakfast if it were a nearly 1,000-calorie affair, and lunch and dinner were eaten in prince and pauper-sized portions, respectively? What about certain human females?
A recent study from Tel Aviv University varied meal timing and calorie distribution for normal-weight women with Polycystic Ovarian Syndrome (PCOS) and measured changes in insulin resistance and fertility rates among them. The 60 participants were randomly assigned to either a “big breakfast” group—consuming 983 calories for breakfast, 684 for lunch, and 190 for dinner—or a “big dinner” group, which kept lunch calories the same and switched the calorie numbers for breakfast and dinner, for 90 days. The study's lead author, Daniela Jakubowicz, MD, has promoted hobbit-friendly breakfasts for weight loss previously.
Past research has found a link between PCOS and insulin resistance, and between symptoms of PCOS, such as irregular ovulation cycles and high levels of testosterone, and fertility problems. Other studies have focused on lifestyle modifications such as weight loss for insulin and hormone management among overweight women with PCOS, and medications including insulin-sensitizing agents may be used to treat hormonal and metabolic conditions associated with PCOS.
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.
According to Prof. Jakobowicz, these results suggest that meal timing – specifically a meal plan that calls for the majority of daily calories to be consumed at breakfast and a reduction of calories throughout the day – could help women with PCOS manage their condition naturally, providing new hope for those who have found no solutions to their fertility issues, she says. PCOS not only inhibits natural fertilization, but impacts the effectiveness of in vitro fertilization treatments and increases the rate of miscarriage.
Study authors indicated that a high-calorie breakfast followed by reduced caloric intake throughout the day could also lessen the impact of common PCOS symptoms, such as unwanted body hair, acne, and an elevated risk of developing type-2 diabetes.
Lynn Westphal, MD, is co-director of Women and Sex Differences in Medicine (WSDM) and an associate professor of obstetrics and gynecology at Stanford whose research interests include infertility and fertility preservation. I asked her for comment on this study. She replied:
I think it’s a really interesting study. I would not have thought that the timing of meals would make that big of a difference in the PCOS patients. A lot of patients don’t eat breakfast or don’t think it’s important, so having a study that shows it has an impact on fertility will help us counsel patients to modify their lifestyle in a way that also benefits their overall health. As a follow up, it would be interesting to see if this benefit is seen during pregnancy, too. We know that the health of the mother during pregnancy can have a significant impact on the long-term health of the child.
Previously: NIH study suggests progestin in infertility treatment for women with PCOS may be counterproductive, Patients turning to acupuncture to boost fertility and The pill works just as well for heavier women, study finds