The Truth About Your Menstrual Cycle and Your Appetite

If you experience an increase in appetite just before a menstrual period, you're not alone. At certain points in your cycle, it's possible you'll be hungrier than usual or crave certain foods. As you might expect, hormones are the culprit.

Premenstrual syndrome (PMS) is a combination of symptoms that many people get about a week or two before their period, as per Office on Women's Health. Appetite changes or food cravings are among PMS symptoms.

But PMS doesn't automatically equal diet disaster, said Joshua Klein, MD, a reproductive endocrinologist at the Icahn School of Medicine at Mount Sinai in New York City.

The Phases of the Menstrual Cycle

Each month during the years between puberty and menopause, your body goes through several changes to get it ready for a possible pregnancy. The menstrual cycle is the term used to describe the monthly hormonal cycle a female's body goes through to prepare for pregnancy, according to the Office on Women's Health.

A menstrual cycle is considered to begin on the first day of a period. The average cycle is 28 days long; however, a cycle can range in length from 21 days to about 35 days.

Your menstrual cycle is divided into four phases:

• Menstrual phase: The first stage of the menstrual cycle. It's also when you get your period.
• Follicular phase: This phase starts on the first day of your period and ends when you ovulate.
• Ovulation phase: This is when your ovary releases a mature egg, usually right in the middle of your menstrual cycle.
• Luteal phase: This occurs after the follicle releases its egg and changes into the corpus luteum, which releases hormones that keep the uterine lining thick and ready for a fertilized egg to implant.

Progesterone Connection

Studies have shown that during the luteal phase of your cycle, which starts with the release of the egg at ovulation and ends when a period begins, you may experience an amped-up appetite.

In a 2015 study published in the European Journal of Nutrition, study authors measured the dietary intake of over 250 healthy, regularly menstruating participants aged 18–44 for two menstrual cycles. They found an increased intake of protein, specifically animal protein, as well as an increase in reported food cravings during the luteal phase of the menstrual cycle independent of ovulatory status.

And a 2016 study published in the Annals of Endocrinology looked at the eating habits, weight fluctuations, and hormone levels of 30 participants ages 18-45. The study researchers found that women really did eat significantly more before their periods. Their daily calorie intake rose from 1,688 during the follicular phase to 2,164 during the luteal phase, with carbs accounting for most of the extra calories.

This symptom may be familiar to many menstruating people. In fact, among the symptoms of premenstrual syndrome, or PMS, is appetite changes or food cravings, according to the Office on Women's Health. What's happening in your body is that post-ovulation, progesterone begins to rise. Progesterone is the hormone that helps prepare the female body to implant and nourish a fertilized egg. If egg and sperm do not meet, a menstrual period follows.

But it's not entirely up to progesterone. Other hormones are counterbalancing that. "For example, leptin, a hormone that suppresses appetite, is higher during the second half of the cycle, too," said Dr. Klein.

In fact, according to a 2021 study in the International Journal of Women's Health, studies analyzed show significant changes in leptin, including a steady increment from the lowest level at the early follicular phase to its peak at the late luteal phase.

The Reason You May Crave Chocolate

Insulin and the happy hormone serotonin dip during the luteal phase, while the stress hormone cortisol increases. According to Johns Hopkins Medicine, hormone changes can cause a serotonin deficiency just before your period. Serotonin is a natural substance in the brain and intestines that narrows blood vessels and can affect mood and cause physical symptoms. What can make you feel better? A fan favorite: Chocolate.

"Chocolate makes you feel good," said Dr. Klein. "The fat and sugars help replenish insulin and serotonin levels in the brain, elevating your mood."

In the 2015 European Journal of Nutrition study, researchers noted that the participants reported a significant increase in appetite and cravings for chocolate, sweets, and salty foods in the late-luteal phase versus the other three phases of the menstrual cycle.

Your Metabolism Gets a Mini Boost

Most people who menstruate burn slightly more calories than normal during the luteal phase, so the extra calories are put to use.

In fact, a 2020 PLoS One study performed a meta-analysis of all English-language available studies on metabolic changes during the menstrual cycle. Thirty English-language studies published between 1930 and December 2019 were included in their review, and 26 studies involving 318 women were included in the meta-analysis. Of these, 47% of studies reported an increase in resting metabolic rate (RMR) during the luteal phase compared to the follicular phase.

"We don't know exactly why," said Dr. Klein, "but it could be that mechanisms are in play preparing for possible pregnancy, which requires more energy expenditure." So it's all right to indulge a bit. You have (a little!) wiggle room.

Summary

Studies and science agree that period cravings are real. As your body goes through several changes (between puberty and menopause) to prepare for a possible pregnancy, hormones rise and fall. Some of those hormonal changes might cause you to have food cravings before your period.