How Menopause affects metabolism and body composition

Understand how menopause affects metabolism, muscle and body composition, plus nutrition, movement and sleep tips to support midlife wellbeing.

The menopause transition and post-menopause years are periods of natural physiological change, and body composition is one area where those changes often become noticeable. According to Better Health Channel, women aged between 45 and 55 gain around half a kilo per year on average, changes that reflect a combination of ageing, hormone shifts and lifestyle factors. What can shift more noticeably than the number on the scales is where fat sits on the body, how much muscle the body carries, and how energy moves across the day.

This article looks at what happens to metabolism, body composition and energy during and after menopause, and the everyday habits that support this life stage.

Why body composition can change during menopause

Menopause is when you have not had a menstrual period for 12 months. According to the Australasian Menopause Society, the average age of menopause in Australian women is 51 years, with most women reaching it between 45 and 55. The transition through perimenopause, menopause and post-menopause spans several years, and across this time the ovaries gradually produce less oestrogen and progesterone.

Two things happen in parallel. Ageing itself is associated with a gradual loss of muscle mass and a slower resting metabolic rate. Declining oestrogen also influences where the body stores fat. As Jean Hailes explains, women often carry weight on their hips and thighs before menopause, and after menopause fat storage tends to shift towards the waist.

A 2026 study published in the Journal of Clinical Medicine found that postmenopausal women showed lower lean body mass, skeletal muscle mass and mineral content compared with premenopausal and perimenopausal women, alongside higher body fat percentage and greater central adiposity. These changes were seen across all body mass categories.

The result is that even when weight stays broadly the same, the ratio of muscle to fat and the distribution of that fat can shift. This is a normal physiological pattern.

Metabolism, hormones and energy explained simply

Metabolism refers to all the chemical reactions the body uses to turn food into energy. Resting metabolic rate, the energy the body uses at rest, accounts for the largest share of daily energy use for most people.

Two things influence resting metabolic rate more than most:

• The amount of lean tissue (muscle, organs, bone) the body carries. Muscle is more metabolically active than fat tissue.

• Age. Resting metabolic rate tends to decline gradually with age, in part because lean mass declines.

According to Better Health Channel, as women get older, they lose muscle mass, which slows metabolism, so if diet doesn't change, weight can gradually creep up. The International Menopause Society recommendations describe the age-related decrease in total energy expenditure as the most important cause of midlife weight gain, with menopause-related oestrogen decline being the major cause of increased abdominal adiposity.

Energy levels can also shift during menopause. Hormonal changes influence sleep quality, mood and body temperature, and each of these can affect how energetic a day feels. Understanding these connections helps make sense of why food, movement and sleep can feel different than they did in earlier decades.

Muscle mass, strength and body composition after midlife

Muscle mass isn't only about strength. It's also a major driver of resting metabolic rate, glucose regulation and functional independence with age. From around age 30, adults tend to lose muscle mass gradually, and this loss can accelerate after menopause.

Two factors are at play:

1. Anabolic resistance: with age, the muscle protein synthesis response to a given amount of protein or exercise tends to be smaller than it was earlier in life. This means older women may need more of both stimulus (protein and resistance exercise) to maintain muscle.
2. Hormonal shifts: oestrogen has a role in muscle maintenance, and its decline contributes to the pattern of lean mass loss seen after menopause.

Research supports adequate protein intake, spread across meals, alongside resistance training to help preserve muscle mass and function in midlife women. Research published in Nutrients identified 1.17 g of protein per kilogram of body weight per day as the minimum intake associated with higher relative skeletal muscle mass in healthy older women. Those meeting this threshold also had lower BMI and lower fat mass than those consuming less. This sits above the general adult protein reference intake and is worth discussing with a GP or accredited practising dietitian for personalised advice.

Why sleep and stress can influence weight changes

Sleep and stress are two of the most overlooked factors in body composition change during menopause. Hot flushes, night sweats and hormonal shifts can disrupt sleep, and shorter or fragmented sleep has been linked to changes in the hormones that regulate appetite.

Poor sleep also affects motivation and energy for movement the following day. Better Health Channel notes that menopausal symptoms such as poor sleep or low mood can make it harder to exercise and eat well, which may contribute to weight gain.

Ongoing stress influences the body's stress hormone system, including cortisol. Sustained cortisol elevation can affect appetite, cravings, sleep quality and where the body tends to store fat.

Everyday practices that support sleep and a steadier stress response include:

• Keeping consistent wake and sleep times
• A cool, dark bedroom
• Reducing caffeine after early afternoon
• Building in short daily pauses to breathe, stretch or walk
• Talking to a GP if hot flushes, night sweats or mood changes are meaningfully affecting sleep

Nutrition habits that support metabolic wellbeing

Nutrition needs shift subtly with age, and the menopausal transition is a good moment to look at what's on the plate. Whole-food dietary patterns that include plenty of vegetables, adequate protein at each meal, whole grains, legumes and healthy fats support metabolic health across midlife. Jean Hailes recommends filling the plate with healthy food choices, enjoying a palm-sized source of protein at main meals to support fullness and steadier blood sugar, and swapping sugary drinks for water while limiting alcohol.

A few habits worth considering:

• Include a source of protein at each main meal. Options include eggs, tinned fish, lean meat, tofu, legumes, dairy or a small handful of nuts.
• Fill half the plate with vegetables at lunch and dinner.
• Choose whole grains over refined carbohydrates most of the time.
• Include calcium-rich foods daily, such as dairy, calcium-set tofu, sardines with bones, and leafy greens. Calcium supports bone health, which is worth prioritising after menopause.
• Aim for regular safe sun exposure to support vitamin D, which contributes to calcium absorption. Talk to a GP if you're unsure whether your levels are adequate.
• Limit alcohol. Alcohol adds kilojoules, can disrupt sleep and may worsen menopausal symptoms.

The role of strength training and daily movement

Movement is one of the most protective factors for body composition and metabolism across midlife. The Australian 24-Hour Movement Guidelines for Adults recommend a mix of activity across each day, including:

• 30 minutes or more of moderate to vigorous intensity physical activity on most days

• Muscle-strengthening activities on 2 or more days per week

• Functional activities targeting mobility, balance and coordination on 3 or more days per week

• Several hours of light-intensity physical activity daily

• 7 to 9 hours of good quality sleep, with consistent bed and wake times

Resistance training deserves particular attention around menopause. A systematic review with meta-analysis published in Climacteric confirmed the benefits of resistance training on physical fitness in healthy postmenopausal women, with significant improvements in measures including maximal oxygen uptake and lower extremity strength. Weight-bearing and resistance exercise also supports bone health, which is worth prioritising in midlife and beyond.

Practical starting points for building strength:

• Begin with 2 sessions per week focused on the major muscle groups (legs, back, chest, shoulders, arms, core)
• Use body weight, resistance bands, free weights or gym machines, depending on what's accessible
• Progress gradually. Adding a little more weight or one more repetition over time creates the stimulus for change
• Work with a qualified exercise professional or physiotherapist if you're new to weights, particularly if you have any joint concerns

Everyday movement matters too. Walking, gardening, taking the stairs, dancing and household activity all count towards a more active day.

Supporting vitality and energy in post-menopause

Alongside diet and movement, some women look at complementary support to help maintain metabolic wellbeing, energy and general health during and after menopause. Nutrients that play a role include calcium and vitamin D, which contribute to bone health and calcium absorption, and magnesium, which is involved in normal muscle function and energy metabolism.

Blackmores Post Menopause Wellness is formulated for adult women in post-menopause. Each tablet contains 162.5 mg of calcium (as calcium hydrogen phosphate dihydrate), 7.5 mcg of vitamin D3 (colecalciferol), 40 mg of magnesium (as magnesium citrate), 100 mg of theanine and 300 mg of fenugreek seed extract (equivalent to 3 g of dried herb). The formulation is designed to help maintain and support body metabolism, energy production, vitality, general health and wellbeing, bone health, healthy stress response and mind relaxation. Vitamins and minerals can only be of assistance if dietary intake is inadequate.

For women earlier in the transition, Blackmores Peri & Menopause Balance is formulated to support the perimenopausal experience. It includes clinically trialled Affron® saffron extract alongside plant-based ingredients including withania (ashwagandha) and fenugreek, and is designed to help relieve hot flushes and night sweats, support emotional wellbeing and mood balance, and support refreshing sleep. Vitamins and minerals can only be of assistance if dietary intake is inadequate.

Always read the label and follow the directions for use.

When weight or body changes should be checked

Some body change is expected around menopause. Certain changes warrant a conversation with a healthcare professional, including:

• Rapid or unintentional weight change
• Persistent tiredness that isn't relieved by rest
• Changes in mood that affect daily life
• Sleep problems that last more than a few weeks
• Any new symptoms that concern you

Midlife is a useful time to book a check-in with a GP to review overall health and discuss any menopausal symptoms. Regular check-ups can also help track things like blood pressure, cholesterol, blood sugar and bone health over time.

Key takeaways for working with body changes, not against them

• Expect body composition to shift, and treat that shift as information rather than a problem to solve
• Prioritise building and keeping muscle. It supports metabolism, strength and how you feel day to day
• Aim for a source of protein at each main meal, and enough of it across the day
• Include resistance training twice a week and stay active most days
• Protect sleep and build in daily ways to steady stress, since both shape body composition over time
• Focus on nourishing your body rather than restricting it. Whole foods, plants and calcium-rich choices go a long way
• Check in with a GP about any changes that concern you or persist, and treat midlife as a good moment for a general health review

Frequently asked questions

Does menopause cause weight gain?

Menopause on its own is not the main cause of weight gain during midlife. Weight gain in this decade is influenced by ageing (which slows metabolism and reduces muscle mass) and lifestyle factors. Hormonal changes do influence where fat is stored, with a shift towards central adiposity after menopause.

Why is belly weight common around menopause?

As oestrogen levels decline, fat storage patterns tend to shift from the hips and thighs towards the waist. In postmenopausal women, belly fat accounts for 15 to 20 percent of total body weight, compared with 5 to 8 percent in premenopausal women.

Can strength training help during menopause?

Yes. Structured resistance training has been shown to support improvements in physical fitness measures such as maximal oxygen uptake and lower extremity strength in healthy postmenopausal women. Muscle-strengthening activities on two or more days per week form part of the current Australian 24-Hour Movement Guidelines for adults.

How do sleep and stress affect weight during menopause?

Poor sleep and sustained stress can influence appetite hormones, energy for movement and cortisol levels, all of which can play a role in body composition change over time. Supporting sleep quality and building in daily stress management can help.

When should I speak with my GP about body changes?

Book a chat with your GP if you notice rapid or unintentional weight change, persistent tiredness, sleep problems lasting more than a few weeks, mood changes affecting daily life, or any new symptoms that concern you. Midlife is also a useful time to schedule a general health check.

Always read the label and follow the directions for use. If symptoms persist, talk to your health professional.

Disclaimer: This article provides general information only and is not intended to diagnose, treat, cure, or prevent any disease. The information presented is not a substitute for professional medical advice. If you have concerns about your health, please consult your GP or healthcare provider for a personalised assessment and recommendations. Supplements should not replace a balanced diet.