Reviewed by

Morgane Leten - Nutrition & Fertility Coach


The Connection Between Weight Loss & Your Menstrual Cycle

Reviewed by

Morgane Leten - Nutrition & Fertility Coach

The new year is a perfect time to start a journey toward better health. It’s the season of resolutions after all and for many women, that includes promises to eat better, exercise more and in some cases, lose weight. Whatever your goals, we’re here to help you, and one of the ways we want to do that is to educate you about your cycle and its potential impact on your wellness goals.

Understanding the relationship between your menstrual cycle and your weight is extremely important. You may be surprised to learn that your cycle's phases can actually significantly impact your weight-related goals.

In this article, we’re diving into the science behind why shedding those extra pounds might seem like a breeze in the first half of your cycle and why those pre-period days might demand a bit more attention and self-care.

How Your Cycle Affects Weight Loss

Have you ever wondered why losing weight feels like a breeze in one part of the month and a monumental task in another? You are not losing your mind. There’s a scientific reason why this happens.

The menstrual cycle is divided into four phases: menstrual, follicular, ovulatory, and luteal. Each phase comes with different hormonal levels, which can impact your metabolism and how much energy you have. Of course, not everyone will experience the exact same changes, and they may even be different from month to month, but generally, your metabolism is slower during the follicular phase of your cycle. This means that you are actually less hungry than you are at other times in your cycle. For example, in the premenstrual phase, your body needs more calories so you’ll feel hungrier then.

Here's a general overview:

Menstrual Phase (Days 1-5):

  • Hormonal Changes: Estrogen and progesterone levels are low.
  • Metabolism: Typically, basal metabolic rate (BMR) is lower during menstruation, which means your body may require slightly fewer calories.

Follicular Phase (Days 6-14):

  • Hormonal Changes: Estrogen begins to rise, peaking just before ovulation. Testosterone also increases.
  • Metabolism: BMR may increase slightly, and some women report increased energy levels. This is a favorable time for physical activity and exercise.

Ovulatory Phase (Days 15-17):

  • Hormonal Changes: Estrogen peaks, and there is a surge in luteinizing hormone (LH), triggering ovulation.
  • Metabolism: BMR may remain elevated, and some women experience an increase in calorie expenditure. Appetite may increase as well.

Luteal Phase (Days 18-28):

  • Hormonal Changes: Progesterone rises, and estrogen decreases.
  • Metabolism: BMR may increase slightly, but some women may experience an increase in cravings and hunger. This is often when premenstrual symptoms occur.

Also, if weight loss is your goal, it’s important to know that during the luteal phase, your metabolism speeds up. This means that calories are burned faster than normal in the week before your period. As a result, your body needs more calories during this period - about one hundred to three hundred extra per day.

The pre-period days can also come with cramps and sometimes cravings, bloating, and a feeling like your weight loss journey is a lost cause. But don’t worry. This is a normal part of your cycle and understanding these changes throughout the month is important. Not only will it help keep your motivation up, it will help you understand exactly what’s happening in your body and help explain why you might not be making progress toward your goals.

Why Does Your Cycle Impact Weight Loss

The simple answer is: hormones. Changes in hormone levels cause all sorts of changes in your body and one of them is your metabolism, which is intricately linked to weight loss.

During the first half of your cycle, estrogen levels are higher which makes your body more sensitive to insulin. Insulin is what allows your cells to use carbohydrates for energy more effectively. Studies have shown a link between estrogen and improved insulin sensitivity which can have a direct impact on your ability to lose weight. Hormonal changes throughout your cycle change your energy levels and your eating preferences, too!

As your cycle progresses into the luteal phase, progesterone levels start to rise. While progesterone is important, studies have shown that it can also cause water retention. This will naturally increase your weight, even if you’ve been focused on healthy eating and exercise. So don’t despair!

On top of increased water retention, progesterone can also lead to cravings. It’s your body’s way of asking for extra fuel which could lead you to feel a little more snack-ish than usual!

So you could be doing everything right on your health journey, but fluctuating hormones are going to add a little extra level of challenge. Estrogen gets the metabolism revved up, while progesterone makes you feel bloated and peckish! Understanding the way your hormones impact the way you feel can help a lot - not only to bring some clarity to the way you feel, but it can also help you navigate the ups and downs of a weight loss journey throughout your cycle.

The Impact of Weight on Menstrual Health

A long history of diet culture and the narrative that “slim-is-king” has been quite damaging for many women and their ability to love themselves. Most women have dabbled with some form of diet or restricted eating at one time or another and we completely understand that for many women, their relationship with food is complicated.

But striving to be healthy isn’t just about fitting into a favourite pair of jeans or seeing a certain number on the scale. It’s about keeping your body’s internal processes in sync. Being too heavy or too light can throw your hormonal balance out of whack, which can cause your cycle to become irregular or disappear altogether. Your period is a great barometer for your overall health, so it’s important to pay attention to irregular periods or if your period goes MIA for a while (this is known as amenorrhea). This is your body’s red flag, signaling something is off.

To keep your cycle in a happy place, it’s important to aim for a healthy weight and that isn’t just about a certain number. Healthy looks different on everyone. It’s about giving your body the support it needs to keep your cycle on track.

What about Fasting and Detoxing?

Intermittent fasting or detoxing is very on trend right now, so it can seem alluring to add these tactics to your routine, especially if losing weight is a goal for you. But before you give them a try, it’s important to understand your body’s internal clock and the impact that fasting or detoxing might have - it could be the opposite of what you’re looking for!

During the luteal phase of your cycle, your body needs stability and fuel. So, things like extreme detoxes or fasting that restrict your food intake for long periods of time make your body think it’s starving, and instead of getting all the benefits of a fast, you might find yourself bloated and uncomfortable with sugar cravings and low energy. One study found that intermittent fasting posed a potential risk to a woman’s hormonal balance and menstrual health. Even things like a low-carb diet might not be good for you.

Whether you’re planning to have a baby or not, a woman’s body is naturally built for reproduction. When you don’t eat for extended periods of time, your body thinks it's starving and it goes into “protect and preserve” mode. This mode is about survival! Your body will actually hang on to weight (in the event you needed to say, survive a famine!) and it increases your hunger hormones signaling to your brain to go get some food ASAP!

It also slows down things like your fertility, so you don’t waste energy on non-essential things like growing a baby.

If you’re not interested in having a baby, this might not sound like a big deal, but when you mess with reproduction, you mess with hormones. And, when your hormones are out of balance, you set yourself up for a whole range of health problems which are very likely the polar opposite of what you are trying to achieve with a detox or fasting.

Intermittent fasting can affect the hypothalamus or the part of the brain that regulates hormones like estrogen. This hormone plays a critical role in your monthly cycle. When this happens, you could notice:

  • Low energy
  • Sugar cravings
  • Weight gain
  • Trouble concentrating
  • Dull hair and skin
  • Fertility challenges

Fasting can also disrupt cortisol production. When this happens, you might notice:

  • Increased anxiety
  • Low energy and brain fog
  • Inability to sleep

It’s important to listen to your body. When it is signaling for nourishment, skip the extremes and opt for wholesome, nutrient-packed foods and gentle, supportive exercises that align with your body's needs. Think of it as giving your body the TLC it craves during this phase—fueling up smartly without throwing it into a tailspin.

We don’t want to deter you. If you want to try a fast or detox, go for it. Just do it, armed with knowledge. Check out our blog post all about fasting and how to fast according to your cycle.

Could Period Problems Be Preventing Your Weight Loss?

If you’re doing everything right and you’re still not seeing the results you hoped for, it could be related to your hormonal balance.

One common reason women don’t lose weight is due to estrogen dominance. This means that your estrogen levels are way too high in comparison to progesterone. Not only can this cause period problems, but high estrogen levels are also connected to water retention and weight gain. To lose weight, you need to get your estrogen levels balanced first.

If your cycle is out of whack, there is essentially no weight loss routine that will yield the results you’re looking for, especially in the luteal phase and premenstrual phase of your cycle. Hormones during this time are going to make you crave sweets, salty stuff and all the things you don’t want to be eating for weight loss. You’ll also have a major energy slump which is going to make you feel way too tired to hit the gym. Consistency is a big challenge when hormones are out of balance.

So, if you address your period problems first, weight loss will come more easily. How do you do that? There’s lots of ways:

If you’re concerned, reach out to us and talk to an expert, or make an appointment with your doctor.

Embracing your Cycle

Understanding the relationship between your menstrual cycle and weight loss can be the key for a more effective and holistic approach to achieving your health goals. The phases of your cycle have a crazy power over your body's metabolism, cravings, and energy levels. By syncing your wellness strategies with your cycle, being mindful of its fluctuations and needs, you can empower yourself to navigate the journey toward a balanced weight and improved well-being more effectively.

Remember, it's not just about the number on the scale but about supporting your body's natural rhythms. So, embrace this knowledge, listen to your body, and go on a journey that aligns with your cycle for sustainable, long-term wellness.