Ketogenic diets may uniquely impact menstrual cycles in pre-menopausal women, finds study

A new study revealed that while both low-carbohydrate ketogenic diets (KDs) and low-fat diets (LFDs) can promote significant weight loss and improve metabolic health, KDs may uniquely impact menstrual cycles in pre-menopausal women. The findings of this research was published in the PLOS ONE journal.

The research was conducted on overweight and obese women aged 34 ± 10 years with an average BMI of 32.3 ± 2.7 kg/m². The outcomes suggests that nutritional ketosis could influence menstrual frequency and intensity. The 6-week study compared the effects of a carefully designed ketogenic diet (~75% of energy for weight maintenance from fats) and an isocaloric/isonitrogenous low-fat diet on various health parameters, including self-reported menstrual changes.

The participants in the KD group were further divided into 2 subgroups where one group received daily ketone salt supplementation (KS), the other group was given a placebo (PL), and a third group followed the LFD protocol.

Both diets led to substantial weight loss (around 7 kg on average) and fat mass reduction (approximately 4.6 kg), along with significant improvements in insulin sensitivity and serum lipid profiles. These changes underline the metabolic benefits of hypocaloric diets, regardless of macronutrient composition. However, fasting plasma glucose and inflammatory markers showed no significant difference between the KD and LFD groups.

A distinguishing feature of the KD was the increase in fasting beta-hydroxybutyrate (a marker of ketosis) by 1.2 ± 0.3 mM, regardless of supplementation. This state of nutritional ketosis coincided with marked menstrual changes in the KD participants. About 30% of women in the KD+KS group and 43% in the KD+PL group reported increased menstrual frequency and intensity within two weeks.

Also, one-third of KD participants regained their menses after a prolonged absence (over a year) by the 4th week. In contrast, no menstrual changes were observed in the LFD cohort. The findings highlight the potential for ketogenic diets to influence female reproductive health beyond their role in weight loss and metabolic improvement.

While the exact mechanisms remain unclear, the study suggests a link between ketosis and hormonal regulation. Overall, the research illuminates the need for further studies to unravel the physiological pathways linking nutritional ketosis to menstrual health by emphasizing the broader impact of diet on well-being of women.

Reference:

Kackley, M. L., Buga, A., Brownlow, M. L., O’Connor, A., Sapper, T. N., Crabtree, C. D., Robinson, B. T., Stoner, J. T., Decker, D. D., Soma, L., & Volek, J. S. (2024). Self-reported menses physiology is positively modulated by a well-formulated, energy-controlled ketogenic diet vs. low fat diet in women of reproductive age with overweight/obesity. In L. Yanes Cardozo (Ed.), PLOS ONE (Vol. 19, Issue 8, p. e0293670). Public Library of Science (PLoS). https://doi.org/10.1371/journal.pone.0293670