In a world of fad diets and restrictive eating plans, the term “calorie” has become a dirty word. It’s often deemed as something that should be avoided or cut back—regardless of your individualized needs. So much, in fact, that consuming fewer calories is frequently seen as a hallmark of good health.
Yet, if you regularly exercise (and hopefully you do!), eating more calories could benefit your reproductive wellness.
According to a 2020 study in the Journal of Endocrine Society, consuming extra calories can help active women prevent menstrual disorders. This includes absent or infrequent menstrual periods (amenorrhea and oligomenorrhea, respectively), along with the associated health effects on the body.
After all, the reproductive system is super receptive to lifestyle habits, including energy intake and exercise. What’s more, these habits are interconnected, meaning that one ultimately affects the other.
Here’s the lowdown on how calories, exercise, and menstruation are interrelated—how upping your food intake can keep your periods in check.
Without enough calories, exercising women are prone to menstrual dysfunction.
Here’s the deal: Your body needs calories to perform basic biological functions, including regular menstruation, muscle repair, and brain activity.
But if you live an active lifestyle, your body needs even more calories to sustain these essential functions. That’s because physical movement uses a lot of energy. Plus, the more muscle you have, the more calories you’ll burn at rest.
If you don’t eat enough to meet these increased requirements, your body will have a hard time doing its thing. You’ll also lose fat mass, which decreases levels of leptin, a hormone that’s made by fat. Leptin is in charge of regulating energy intake and balance.
And if leptin levels are low? The hypothalamus in your brain secretes less gonadotropin releasing hormone (GnRH). This is an issue because GnRH normally makes your pituitary gland (also in the brain) release luteinizing hormone (LH) and follicle stimulating hormone (FSH). LH and FSH tell the ovaries to make estrogen.
But if GnRH levels dip, LH and FSH can’t send the appropriate signals, and the endometrium doesn’t thicken in the follicular phase. It stays thin and doesn’t shed, resulting in infrequent or absent periods.
It’s worth noting that low energy intake can happen for many reasons.* A review in Sports Health shares that some female athletes simply don’t realize that they’re not eating enough. Lack of time or poor appetite can also play a role. And then there’s the ongoing narrative within the wellness community that favors calorie restriction. This can make women feel guilty for eating more, even when their bodies need it.
*If low calorie consumption is related to an eating disorder, it’s essential to get help from a mental health provider.
Having infrequent or no periods can lead to a wide range of complications.
You’ve likely heard about female athletes totally “losing” their periods. This condition, known as the Female Athlete Triad, involves:
- Reduced energy availability (with or without disordered eating)
- Menstrual dysfunction (infrequent or absent periods)
- Low bone mineral density
Yes, that’s right—lack of periods is associated with poor bone health. That’s because estrogen helps regulate bone-related hormones. This decline in bone health increases the risk of stress fractures (ouch), along with fatigue and decreased athletic performance.
The Female Athlete Triad can also lead to other complications like abnormal blood cholesterol levels, impaired function of the endothelium (lining of the heart and blood vessels), and temporary infertility.
Research has found that eating more can improve menstrual disorders in active women.
So, back to that study in the Journal of Endocrine Society. It involved 62 young female athletes with infrequent periods. For 12 months, 32 of the women ate an extra 300 to 400 calories a day, while the remaining 30 followed their typical diet.
At the end of the study, the women who ate more calories experienced higher leptin levels. They were also two times more likely to have periods than the women who ate their usual diet. According to the researchers, these findings suggest that eating more calories can help active women get their period back on track—and avoid the complications related to losing it in the first place.
You need more calories during your luteal phase, too.
Even if you’re not physically active, you also need extra calories during the luteal phase of your menstrual cycle.
The luteal phase begins right after ovulation and ends on the first day of your period. It’s also when the dreaded premenstrual syndrome (PMS) usually sets in. Generally, the phase lasts 10 to 14 days, but everyone is different.
During the luteal phase, your body makes more progesterone. This increases your body temperature and energy expenditure, so you burn more calories during basic functions like breathing and digestion. Progesterone also stimulates your appetite, which explains those crazy PMS cravings.
Simply put, your body needs more calories before your period, but remember: This isn’t a free pass to overindulge in those cravings. Instead, fuel on nutrient-dense, whole foods like nuts, whole grains, and eggs. Not only will this give your body enough energy, but it can reduce the intensity of PMS symptoms too. (Need a few tips? We’ve got you. Check out our PMS meal plan.)
For personalized guidance, work with a dietitian.
Whether you’re a competitive athlete or casual exerciser, aim to consume extra calories to meet your body’s requirements. If possible, meet with a dietitian for personalized advice, especially if you are very active or have infrequent periods. The same goes if you have any underlying medical conditions, which might affect how your body responds to exercise or increased calorie intake.
A dietitian can also offer suggestions for nutritious, high-calorie meals. Until then, remember that calories are necessary to support physical activity, biological function, and reproductive health. Bottom line? Eating more might be just what you need to become a healthier, stronger athlete.
ABOUT THE AUTHOR
Learn more about Kirsten at k-nunez.com