What is intermittent fasting?
Intermittent fasting (IF) is a weight loss method that involves creating regular periods of eating and fasting.
According to research published in the journal Canadian Family Physician, this type of fasting is done by fasting for about 16 hours daily or fasting for 24 hours every other day. Intermittent fasting is considered a treatment for obesity.
How does intermittent fasting affect the menstrual cycle?
According to a study published in Thyroid — the official journal of the American Thyroid Association — intermittent fasting may affect the menstrual cycle because it affects the hypothalamus — a part of the brain responsible for regulating hormones like estrogen that are important for the menstrual cycle.
Obstetrician-gynecologist Dr. Deepa Dewan (India) says that intermittent fasting can affect the menstrual cycle and overall reproductive health. Here's how IF can affect the menstrual cycle:
Effects on the hormone leptin
Leptin is a hormone produced by fat cells that helps regulate appetite and energy balance. Intermittent fasting can affect leptin levels in the body. Low leptin can disrupt the release of gonadotropin-releasing hormone (GnRH), which in turn affects the production of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
This hormonal disruption can lead to irregular or absent periods, potentially affecting fertility.
Effects on insulin and cortisol
Insulin regulates blood sugar levels and plays an important role in reproductive health. Intermittent fasting improves insulin sensitivity, which may affect reproductive hormones.
On the other hand, cortisol is a stress hormone that can affect reproductive hormones. Intermittent fasting can increase cortisol levels, especially if the fasting regimen is stressful or results in an energy deficit.
Weight loss effect
Excessive calorie restriction can lead to hormonal imbalances, causing irregular periods or amenorrhea. Additionally, losing too much weight can disrupt your menstrual cycle.
Intermittent fasting may not affect your menstrual cycle or fertility if only applied for a short period of time, especially when the diet does not restrict your calorie intake too much and cause nutritional deficiencies.
