From the Guidelines
Intermittent fasting and one meal a day (OMAD) diets are generally not recommended for individuals trying to conceive naturally or through IVF, as they may potentially harm fertility by disrupting hormonal balance. When considering the impact of diet on fertility, it's essential to prioritize nutritional approaches that support reproductive health. The evidence suggests that obesity may have a detrimental effect on male reproductive function, with studies indicating a negative association between semen parameters and obesity 1. While the provided study does not directly address the effectiveness of intermittent fasting or OMAD for fertility and IVF, it highlights the importance of weight management and nutritional interventions in supporting reproductive health. Key points to consider include:
- The potential negative impact of obesity on semen parameters, including morphology, ejaculate volume, and total sperm count 1
- The importance of standardized methods for assessing obesity and its effects on reproductive hormones
- The need for well-controlled, population-based trials to fully understand the relationship between obesity and reproductive function
- The potential benefits of a balanced diet, such as a Mediterranean-style diet, in supporting fertility and reproductive health. In the context of fertility and IVF, it is crucial to prioritize nutritional approaches that provide consistent energy and nutrients, supporting reproductive function without triggering stress responses that can occur with extended fasting. Always consult with a reproductive endocrinologist and nutritionist before making significant dietary changes when trying to conceive.
From the Research
Effectiveness of Intermittent Fasting for Fertility and IVF
- Intermittent fasting, particularly time-restricted feeding (TRF), has shown potential in improving reproductive health and fertility in women with Polycystic Ovary Syndrome (PCOS) by addressing core pathophysiological mechanisms such as hyperandrogenism, insulin resistance, and menstrual irregularities 2.
- Studies have reported significant improvements in menstrual regularity, with 33-40% of participants reporting normalized cycles, as well as reductions in total testosterone, free androgen index, anti-Müllerian hormone (AMH), and luteinizing hormone (LH) levels, alongside increased sex hormone-binding globulin (SHBG) 2, 3.
- Intermittent fasting has also been found to improve insulin sensitivity, reduce body weight, and decrease inflammatory markers, all of which contribute to enhanced reproductive outcomes 2, 4.
Impact on Reproductive Hormone Levels
- Intermittent fasting has been shown to decrease androgen markers, such as testosterone and the free androgen index (FAI), while increasing sex hormone-binding globulin (SHBG) levels in premenopausal females with obesity 3.
- In men, intermittent fasting has been found to reduce testosterone levels in lean, physically active, young males, but it did not affect SHBG concentrations 3.
- The effects of intermittent fasting on reproductive hormone levels may have varied health implications, including potential benefits for treating hyperandrogenism in females with PCOS and potential negative effects on metabolic health and libido in males 3.
Comparison to Other Dietary Interventions
- The efficacy of intermittent fasting appears broadly equivalent to that of standard daily energy restriction, although many models of intermittent fasting do not involve fed-fasted cycles every other 24-hour sleep-wake cycle and/or permit some limited energy intake outside of prescribed feeding times 4.
- Further research is needed to confirm the findings and establish intermittent fasting as a standard therapeutic option for PCOS management and other reproductive health conditions 2, 3.