Intermittent fasting through the menstrual cycle

By zainab sarwar
Tue, 05, 24

Intermittent fasting can be a powerful tool for weight loss and health improvement when aligned with the menstrual cycle’s physiological and hormonal fluctuations, writes Zainab Sarwar, a Dubai-based nutritionist. Read on…


Intermittent fasting (IF) has gained popularity as a method for weight loss and health improvement. When tailored correctly, it can align with the female hormonal landscape, particularly throughout the menstrual cycle, to optimise results while supporting overall well-being. Understanding the intricacies of doing intermittent fasting during different stages of the menstrual cycle is crucial for women looking to support weight loss in a healthy and sustainable way.

Intermittent fasting through the menstrual cycle

The most crucial aspect of aligning intermittent fasting with the menstrual cycle is listening to the body’s signals. Hormonal fluctuations can vary significantly from one woman to another, making personalisation key to success. If energy levels are low or hunger is persistent, it may be necessary to adjust fasting periods accordingly. Staying hydrated, ensuring a nutrient-dense diet, and prioritising quality sleep are also essential components of a successful intermittent fasting strategy. Before we dive into the details, let’s first understand the menstrual cycle. The menstrual cycle can be divided into four main phases: menstrual, follicular, ovulation, and luteal. Each phase is characterised by specific hormonal changes that can affect energy levels, metabolism, and appetite.

1. Menstrual Phase (Days 1-5): The cycle begins with menstruation, marked by lower hormone levels. It’s a time when energy might be lower, and some women experience fatigue.

2. Follicular Phase (Days 1-13): This phase starts on the first day of menstruation but overlaps with it. Oestrogen levels start low and then rise. Energy levels and mood often improve as the phase progresses.

3. Ovulation Phase (Day 14): Oestrogen peaks, leading to ovulation. This is when many women feel their best, with high energy and mood.

4. Luteal Phase (Days 15-28): After ovulation, progesterone rises, preparing the body for a potential pregnancy. Appetite and cravings can increase, and some women may feel more emotional or irritable.

To effectively integrate intermittent fasting with the menstrual cycle, consider how fasting might align with or work against these hormonal fluctuations.

Menstrual and early follicular phases: During the menstrual and the early follicular phases, energy needs can be higher due to the body’s recovery from menstruation. Fasting might be more challenging, so it’s a good time for shorter fasting periods, such as the 12:12 method (12 hours fasting, 12 hours eating window). Emphasising nutrient-rich foods during the eating window can help support the body’s recovery and energy needs.

Late follicular and ovulation phases: The late follicular phase and ovulation can be the optimal time for more extended fasting periods, such as 16:8 or even 18:6, if tolerated well. Ovulation typically occurs around day 14 of a 28-day menstrual cycle. During this phase, oestrogen levels peak, and your body’s energy needs may remain elevated. That’s the time you may experience bloating, constipation, increased hunger, mood swings, changes in sleep pattern etc. The rise in oestrogen boosts energy and mood, potentially making it easier to extend fasting periods. During this phase, focusing on a balanced diet rich in fibre, proteins, and healthy fats can maximise energy and support overall health.

Luteal phase: The luteal phase can be challenging due to increased appetite and potential cravings. It may be beneficial to switch to a more lenient fasting schedule, such as 14:10, to accommodate higher energy needs and prevent overeating during the eating window. Supporting the body with complex carbohydrates, proteins, and healthy fats can help manage cravings and mood swings. Additionally, incorporating mindfulness practices or gentle exercise can help manage stress and emotional fluctuations that might lead to overeating. For women having PCOS, luteal window is the best time to lose more weight hence it is highly recommended to adapt to 16:8 or even 20:4 schedule if well tolerated at this point.

The role of exercise: It is an important factor in weight loss and overall health. During the menstrual cycle, a woman’s exercise capacity and recovery can vary. It’s beneficial to align exercise intensity with the menstrual cycle phases. For instance, high-intensity workouts may be more suitable during the ovulation phase when energy levels are higher, whereas the luteal phase might call for more moderate or gentle exercise forms. That’s why I always offer different intensity yoga session every day to cater to varying needs of women in general in my yoga classes.

Cut down on caffeine: If you want to follow intermittent fasting then reduce your caffein intake during the eating window. The strategy can offer potential benefits such as improved quality of sleep, reduced anxiety, enhanced hydration, better insulin sensitivity, increased energy levels, and improved adrenal health as high caffeine intake can stress the adrenal glands by constantly stimulating the production of stress hormones such as cortisol and adrenaline. During intermittent fasting, the body is already adjusting to a new eating schedule, and reducing caffeine intake can help minimise additional stress on the body. Intermittent fasting aims to shift the body’s source of energy from glucose to fat. Caffeine, however, can sometimes interfere with this process by impacting blood sugar and cortisol levels. Reducing caffeine can potentially make intermittent fasting more effective by allowing the body to adjust to this energy shift more smoothly.

Point to ponder: While these benefits are significant, it’s also important to note that moderation is the key. Some people may not need to eliminate caffeine entirely but rather limit its intake to earlier in the day or reduce the overall amount consumed. As with any dietary or lifestyle change, it’s a good practice to listen to your body and adjust based on your individual reactions and goals. In order to curb your caffein craving, introduce spearmint tea and it can be easily consumed during the fasting window as well.

Intermittent fasting can be a powerful tool for weight loss and health improvement when aligned with the menstrual cycle’s physiological and hormonal fluctuations. By tailoring fasting and eating windows, as well as dietary choices to the different phases of the menstrual cycle, women can support their hormonal health, manage appetite and cravings, and optimise energy levels. Listening to the body’s cues and adjusting as needed, coupled with professional guidance, can ensure that intermittent fasting is a sustainable and beneficial practice for women seeking to lose weight and enhance their well-being.

Zainab can be reached at, and @lifestylebyzainabsarwar on Instagram