Perimenopause weight gain: Here’s why it happens

It’s normal for your weight to go up and down throughout your life, and a number of factors could be the cause. Having a baby, recovering from an injury, dealing with stress, or simply moving less and eating more can all directly impact your body. 

But if you’re anywhere between your late 30s and your 50s, there could be another factor behind weight gain. If you’ve also been experiencing other symptoms lately such as unpredictable periods, hot flashes, and brain fog, the extra weight you’ve noticed could be linked to perimenopause, signaling the start of your journey toward menopause. 

Menopause is a normal transition that all women and people who have periods go through, but everyone experiences it in their own way. For some, the symptoms can be difficult to live with, while others may not notice any signs at all or won’t be bothered by them. 

If your clothes are feeling tighter, but nothing you do seems to make much difference, it can be frustrating. But try to be kind to yourself. This is something lots of people experience, and there are also plenty of things you can do to help if you want to. In the meantime, it may be helpful to understand why it happens so you can decide if there are any lifestyle changes you want to make.

Here, Dr. Sarina Schrager, family physician and professor of family medicine and community health, University of Wisconsin-Madison, Wisconsin, US, shares everything you need to know about perimenopause weight gain, including what to expect and how to manage it if you want to. But if you have any questions or concerns, always reach out to your doctor for advice.

Key takeaways

• Weight gain is common during perimenopause. On average, women gain about 1.5 kg (just over 3 lb) per year during perimenopause. 
• The makeup of our bodies (our body composition) also naturally changes as we age. Women tend to lose muscle mass, which can impact metabolism (how fast our bodies use the food we eat as energy), making it harder to lose weight.
• Changing hormone levels are believed to be a factor behind perimenopause weight gain.
• It’s also common to move less during perimenopause, and doing less day-to-day activity can make a difference to your weight. 
• Simple lifestyle changes, including doing regular exercise, prioritizing sleep, limiting certain types of food, and drinking plenty of water, can all help you to maintain a healthy weight.

What causes perimenopausal weight gain? 

Before we get started, it’s worth remembering that we all come in various shapes and sizes, and everyone is unique. Your healthy weight will depend on a number of factors, including your age, height, body composition, muscle mass, and race. The most important thing to focus on is being the healthiest (and happiest) version of yourself possible. 

Only you know how your body usually feels. If you feel heavier despite your food intake and exercise levels remaining the same, it could be linked to perimenopause. Fortunately, there are lots of things you can do to feel fit and healthy at this time (and any other).

If you’re unclear on what perimenopause is and when it usually starts, think of it as your transition through menopause, which is your last ever period. It covers the years leading up to menopause and also the year afterward, at which point you can be sure your periods have stopped. 

Perimenopause usually starts in your 40s, but it can happen anywhere between your late 30s and 50s. It can take between four and eight years before your periods stop altogether, but on average, perimenopause lasts about four years. Menopause itself usually happens between the ages of 45 and 55, and from then on you are postmenopausal.

Dr. Schrager explains that there are a number of ways the menopause transition is linked to weight gain:

• Changing hormones: In preparation for the end of your monthly cycles, your hormones start shifting until they begin steadily dropping. This hormonal roller coaster can trigger other changes in the body, which include some of the signs of perimenopause you may have heard of, like hot flashes, joint pain, and mood swings. It can also lead to weight gain. “The decreasing estrogen and progesterone levels can cause the change in body fat from your hips and thighs to your abdominal area,” says Dr. Schrager. 
• Body composition: From our 30s or 40s, we gradually start to lose muscle mass, and as this progresses it can directly impact weight. “Your basal metabolic rate (or metabolism) is the amount of calories you burn just by living — not counting exercise,” Dr. Schrager explains. “Muscle burns more calories at rest than fat does. So, eating the same amount could cause weight gain as you age simply because you have less muscle.” 
• Lifestyle changes: Lots of us are juggling different life stresses by the time we reach our 40s, such as caring for aging parents, working demanding jobs, or parenting. This can make it harder to fit in exercise or make time to cook healthy food, both of which can impact your weight.
• Not enough good sleep: Getting enough sleep can also play an important role in your weight. “It is common for perimenopausal women not to sleep as well as younger [people], which can also cause a decrease in basal metabolic rates,” explains Dr. Schrager.

Can perimenopausal weight gain negatively affect my health?

While it’s normal for your body to change at different stages throughout your life, it is worth keeping an eye on any bigger fluctuations for health reasons. Carrying extra weight at any stage of life — including perimenopause — can impact your health. 

“Increased body fat, especially abdominal fat, is a risk factor for cardiovascular disease,” Dr. Schrager says. “Increased body weight can also lead to higher rates of insulin resistance [when the hormone that regulates your blood sugar doesn’t work properly], prediabetes, and diabetes. Also, living in a larger body can lead to more strain on joints and can increase the risk of hip and knee pain,” she adds. 

That said, health isn’t just physical. We know weight can be a sensitive issue, and it can come hand-in-hand with self-esteem issues. So, while it can be very easy to fall into the trap of comparing yourself to others (many of us have been there), remember that your body type is unique to you. Sizing yourself up against people who have different genetics and different metabolisms is not a fair comparison to make, so try to avoid doing this, especially if it leaves you feeling inadequate. 

If you have any concerns about your health or you’d like some help rethinking your diet and exercise routine, reach out to your doctor. They can offer advice to help decide what’s best for you. Chatting with others going through similar things can also help. Secret Chats in the Flo app is a safe, anonymous, supportive space where people discuss their health and well-being, including perimenopause. Download the Flo app now to join the conversation.

How to manage weight gain during perimenopause

If you’d like to lose weight, but you’re finding it hard, there are a number of things you can do.

Prioritize exercise

The first rule of being healthy at any age is to exercise if you’re able to, explains Dr. Schrager. “For perimenopausal women, continuing a regular exercise program is imperative,” she says. 

For the best results, aim to incorporate the following into your weekly routine:

• Cardio: “At least 150 minutes per week of moderate exercise like walking or biking,” says Dr. Schrager.
• Weight training: “[This is] especially important for perimenopausal women to maintain muscle mass and keep bones strong,” she adds. 
• Keep moving: Stay active day to day by walking, gardening, and taking the stairs. To minimize joint pain, aim to do some type of stretching such as yoga.

If you have any physical limitations that mean exercising certain parts of your body isn’t straightforward, chat with your doctor about how you can make physical activity work for you. 

Switch it up

If you exercise regularly, but you’re no longer seeing the results you hope for, it might be time to try a different fitness routine. “Many [people] don’t understand how they can be eating the same amount and exercising the same amount and still gain weight,” says Dr. Schrager. “But if you’re doing the same regimen every day, you will start burning fewer calories since your body gets used to it. Working out with a trainer or changing your exercise routine could help give you better results.” 

Enjoy nutritious food 

Making healthy diet choices is important at any age, whether you’re perimenopausal or not. “Try to avoid excess alcohol and caffeine, drink plenty of water, [limit] high-fat foods, cook at home as much as you can, and focus on getting at least five servings of fruit and vegetables every day,” suggests Dr. Schrager. 

It’s also a good idea to focus on getting a decent protein and fiber intake during the menopause transition, too. Think meat, fish, certain grains, and some dairy products for protein and whole grain foods, fruits, and vegetables for fiber. If you’re not sure where to start when it comes to a balanced diet, ask a dietitian for help with meal planning. 

Get adequate rest and sleep

Sleep is the cornerstone of good health at any age, yet disrupted sleep is a common complaint in perimenopause. Perhaps unsurprisingly, research has found that hot flashes at night — night sweats — can result in broken sleep. Numerous studies have also found a direct link between lack of sleep and weight gain. “As women age, and with hormonal changes, sleep gets less restorative and more interrupted, slowing down your metabolic rate,” says Dr. Schrager. “Also, obstructive sleep apnea [when your breathing stops and starts while you sleep] can also lead to a slowing of metabolic rate, and [this becomes more common] as people age.” 

Everyone is different, but guidelines suggest that adults should aim for seven or more hours of sleep per night. We know that can be easier said than done. But you can improve your chances of getting enough rest by focusing on good sleep hygiene.

• Aim to go to bed at the same time every night.
• Keep your bedroom quiet, cool, and dark.
• If night sweats are keeping you awake, try setting your thermostat slightly lower than usual.
• Invest in lightweight and breathable bedding and nightwear to keep you cool.
• Cut out or reduce alcohol, caffeine, and spicy foods in the evening. These can all cause your temperature to spike.

Connect with others

If you’re finding things difficult, support can really help. Open up to family, friends, your doctor, or the community in Flo’s Secret Chats for support. Confiding in friends about how you’re feeling can make a big difference, especially if they’re around the same age and also struggling with perimenopause-related weight gain. And you can support each other by meeting up to exercise. Taking up a new sport or going to an exercise class is often easier when you share the experience with friends.

How to feel healthy and confident during perimenopause

Everybody experiences perimenopause differently. As we’ve seen, rethinking parts of your lifestyle could be worth a try to ease certain symptoms that can be linked to your hormonal changes. Alongside trying to maintain a healthy diet and fitting in exercise, trying to keep stress to a minimum, drinking plenty of water, and avoiding smoking are all good ideas to help you feel more like yourself again.

But if you’re doing all this and the scales still aren’t budging, it’s worth keeping in mind that your weight is just a number. “Focusing on fitness and how you feel may be more important than always looking at the scale,” says Dr. Schrager. “While looking at weight and body mass index (BMI) is a way that [doctors] can assess risk factors, they don’t tell the whole story,” she adds. “If you focus on eating healthy and exercising to feel good, that can be the outcome you are looking for.”