Fasting and Your Menstrual Cycle: Everything You Must Know to Successfully Fast While on Your Period

The great thing about fasting is that anybody can try and benefit from it one way or another. However, compared to men, women have more difficulty balancing hormonal changes that come with fasting with their natural hormonal fluctuations. This hormonal madness can mess up your menstruation cycle and eventually discourage you from fasting. To effectively enjoy the benefits of fasting you must thoroughly understand the impact fasting has on your ever-changing hormones.

In this article, we will learn about the role of fasting while on your period, how to go about it, and the do’s and don’ts of fasting while menstruating. And answer the ultimate question, is it a good idea to do intermittent fasting while on your period?

Fastic can accompany you every step of the way with comprehensive fasting support and handy tools to safely monitor your fasting habits during your period.

First Things First: Understanding the Menstrual Cycle

Before getting on to the good stuff, let’s first learn how the menstrual cycle works and its effects on your body.

Menstrual Phase

This phase marks day 1 of your menstrual cycle. The lining of the uterus (endometrium) is at its thinnest and sheds blood and tissue from the previous cycle, usually lasting between 3 to 7 days. During this phase, estrogen and progesterone levels are at their lowest, causing the upper layers of the uterine lining to shed and leave the body.

Follicular (Proliferative) Phase

The follicular phase begins once menstruation ends and lasts until ovulation, typically around day 14 in a typical 28-day cycle. During this time, the uterine lining builds back up in response to rising estrogen levels. Follicle-stimulating hormone (FSH) promotes the growth of ovarian follicles, each containing an egg. The ovaries prepare these eggs for release, and the uterine lining thickens in preparation for a possible pregnancy.

Ovulation Phase

Ovulation takes place around day 14, or the midpoint of the cycle. A mature egg is released from one of the ovaries. Estrogen levels are at their highest and signal the brain to release luteinizing hormone (LH), which triggers the release of the egg. Once the egg is released, estrogen levels start to decline.

Luteal Phase

The luteal phase spans from ovulation to the start of your next menstrual period. This phase lasts around 14 days, usually from day 14 to day 28. Progesterone levels rise to prepare the uterine lining for a potential pregnancy. If no pregnancy occurs, estrogen and progesterone levels decrease. This decrease in hormones leads to the shedding of the uterine lining and the start of menstruation. These hormonal changes can trigger premenstrual symptoms such as mood swings, bloating, and headaches.

Can You Fast While on Your Period?

Yes, you can fast while on your period. But be aware that fasting can affect ovulation and your menstrual cycle overall. Practicing intermittent fasting affects female sex hormones, so knowing exactly when to fast during your period is vital for a smooth fasting experience.

Is It Safe to Fast During Your Period?

Fasting during your menstrual cycle is safe, however, you should know when and how to do it. Knowing the optimal times to fast will help your body maintain its regular menstrual cycle and successfully encourage the effects of fasting.

It is recommended not to fast if you are trying to conceive, are pregnant, or are breastfeeding. Fasting while breastfeeding can impact the quality and quantity of your milk, thus impacting your baby’s health. Women can benefit from intermittent fasting during menopause because it can aid with belly fat and hormone imbalance.

How Does Fasting Impact Hormones?

Intermittent fasting can potentially decrease estrogen levels. Lower estrogen levels can impact your menstrual cycle due to a decline in kisspeptin. Kisspeptin is a reproductive hormone that helps regulate the secretion of LH and FSH (previously mentioned), both of which play crucial roles in the menstrual cycle.

Stress is another factor by which fasting can impact hormone levels. Elevated stress levels promote the release of corticotropin-releasing hormone (CRH), which stimulates the release of cortisol. Cortisol can suppress the release of LH (remember that LH triggers ovulation), consequently impacting the menstrual cycle.

Sex hormones like estrogen and progesterone are mainly regulated by gonadotropin-releasing hormone (GnRH). The release of CRH can negatively impact GnRH regulation and stimulate the release of adrenocorticotropic hormone (ACTH) and cortisol.

Natural hormonal fluctuations throughout your menstrual cycle, everyday stress, and the additional stress that comes with fasting can collectively increase overall stress levels, potentially impacting your menstrual cycle. Therefore, it is crucial to identify the optimal time to fast during your menstrual cycle to minimize these effects.

Benefits of Intermittent Fasting While on Your Period

Practicing intermittent fasting while menstruating can offer multiple advantages, including:

How to Fast During Your Menstruation Cycle?

Just as no woman has the same menstrual cycle experience, no person will experience the same effects from fasting. Science says syncing your fast with your menstrual cycle can help maintain hormonal balance and lessen stress levels.

Here is how you should fast during each phase of your menstrual cycle:

Menstrual Phase

During this time, estrogen levels are low while the body is starting to build up its levels. Due to this, it is an optimal time to fast, particularly overnight for 12 to 14 hours. It is recommended you start around day 2 or 3 of your period.

Follicular Phase

Estrogen levels are higher and your body is pumping energy, which allows for longer fasting periods if desired. You can increase your fasting period by one or two hours, three if you’re feeling daring. You can also engage in high-intensity workouts.

Ovulation Phase

Decrease the fasting period to 12 to 14 hours, or even less if your energy levels are too low. Adjust your fasting schedule based on specific energy levels. Temperature rises so diminishing workout intensity is crucial.

Luteal Phase

At this period of your menstrual cycle, you can relax on the fasting by shortening the fasting periods or stop fasting overall. Tone down workout intensity and go for low-intensity exercises like swimming, gentle pilates, or yoga.

Adjusting your fasting schedule is allowed. You are not bound to the same fast for all eternity. If you notice your body is struggling to endure the fast, broaden your eating window. After a cycle or two, you will learn what fasting approach and routine harmonizes best with your unique menstruation cycle.

Take the Fastic quiz to get a personalized intermittent fasting plan tailored to your background, objectives, and eating habits.

What to Eat While Fasting on Your Period?

Healthcare professionals believe that poor eating habits trigger hormonal imbalances. Incorporating a balanced, nutrient-dense diet and practicing conscious fasting can alleviate hormonal imbalance.

Menstrual Phase

Maintain optimal hydration. Proper hydration levels during fasting prevent constipation and potential bloating. Aim for foods high in iron like leafy greens, red meat, and legumes. Quinoa, spinach, and whole grains are magnesium-rich foods that aid with menstrual pain. Foods to eat during this time are shellfish, pork, pumpkin seeds, black beans, and red berries.

Follicular Phase

Insulin sensitivity is at its prime. Carbohydrate consumption can increase to give you energy for workouts during fasting. Complex carbohydrates like fruits, and starchy vegetables are recommended. Foods to eat during this time are trout, chicken, fermented foods, citrus, and wheat.

Ovulation Phase

Insulin sensitivity starts to decline, therefore you should eat carbohydrates with a low glycemic index like fruits and vegetables, beans, low-fat dairy, and nuts. Good options include vitamin D foods like salmon, eggs, and fortified milk. Foods to eat during this time are tuna, lamb, apricots, corn, and eggplants.

Luteal Phase

Your body is busy preparing for a possible pregnancy, leading to a higher expenditure of proteins and fat. Prioritize getting healthy fats from foods like fish, nuts, and avocado. High-protein foods and fiber provide sustained energy and help manage blood sugar levels to avoid cortisol spikes. Foods to eat during this time are red meat, berries, ginger, turkey, and dates.

What Should You Not Eat While on Your Period?

The foods we eat impact our symptoms before and during menstruation. Avoiding specific food groups helps us narrow down our foods to healthier options and guides us toward a more fast-friendly diet.

Foods you should steer clear from during your period include:

Sugary snacks and beverages that can cause blood sugar fluctuations.
High-sodium foods can lead to water retention and bloating.
Processed foods. No need to explain this one.
Caffeine can stimulate headaches and edemas.
Alcohol can dehydrate your body.
Spicy foods irritate your stomach and consequently affect your menstrual symptoms.

Syncing Is the Key to a Successful Fast

As you have learned, fasting while on your period is not detrimental, as long as you know when and how to do it. Following the proper nutritional recommendations and syncing your fasting routine with your menstruation cycle will potentialize fasting effects, potentially help hormonal imbalance, and promote a healthier lifestyle overall.

Discover other ways the Fastic app can maximize your fasting experience during your menstrual cycle.

Disclaimer: It is advised to speak with a health professional before beginning intermittent fasting or a diet program. There may be side effects for people with certain medical conditions.