MyMT™ Blog

The science behind your changing shape in menopause.

Not all women put on weight in menopause – in fact, some women need to gain weight as they are too thin, but if you are putting on belly fat and your diaphragmatic fat is increasing, as you reach your early to mid 50’s, then I have some questions for you:      

  • Can you breathe easy when you exercise or walk fast? 
  • Are you sleeping all night, every night? 
  • Are you heavier now, than throughout your life?
  • Are you losing muscle tone or you have sore joints and muscles? 
  • Do you feel bloated, ‘puffy’ and tight, especially in your breasts?
  • Do you feel excessively tired after a meal?
  • Do you feel easily frustrated and irritable?
  • Are you on HRT but this isn’t helping your weight gain (or your hot flushes) now that you’re in post-menopause?
  • Are you currently exercising a lot, but this still isn’t helping you lose weight like it did in the past?

I thought so. This was me too. At the time, I had no idea how much our changing shape in menopause is influenced by our poor sleep, our current lifestyle, our changing liver and gut health in menopause, nutrition and exercise advice that isn’t targeted towards women in mid-life and the fact that as we lose oestrogen, we also lose muscle tone and size too.

The combination of these factors change our metabolism. Add to this, that with the loss of muscle tissue, we also lose size in our essential mitochondrial cells. This means that we aren’t burning fat the way we used to prior to our menopause transition. 

These factors create the ‘perfect storm’ for our waist circumference increasing, as well as changes to diaphragm and belly fat during our menopause transition. But we can’t ignore it, because if we don’t stop the menopause weight gain mayhem, then this may lead millions of women into post-menopause heart disease, obesity, Type 2 diabetes and hot flushes that hang-around into post-menopause.

And don’t be fooled that doing lots of exercise is the answer. It isn’t – especially if you aren’t sleeping. The combination of heavy exercise and insomnia leads many women towards adrenal fatigue – symptoms which mimic menopause symptoms. 

Physiology is the science of how the body works and having taught university-level physiology for years, I began to piece together the real science behind my own weight gain and why, not one thing I was doing at the time, was working.

As I began the long lonely hours of undertaking my doctoral studies, I became absorbed in the real science of mid-life weight gain. The weight-gain trajectory that we go on as our hormones change, is something that isn’t being taught to exercise and nutrition professionals here in New Zealand. I know this, because in my doctoral defence I argued that women in mid-life were being forgotten when it came to understanding health changes in mid-life.

It was no surprise that at the online Diabetes Symposium I attended last weekend, that I heard Professor Roy Taylor from the University of Glasgow mention that women between the ages of 50 – 59  years were one of the highest cohorts to develop Type 2 diabetes. With a 15kg weight gain in my early 50’s, this was the slippery slope that I was on too. 

But as I began the long lonely hours of undertaking my doctoral studies, I became absorbed in the real science of mid-life weight gain. The weight-gain trajectory that we go on as our hormones change, is something that isn’t being taught to exercise professionals here in New Zealand. I know this, because in my doctoral defence I argued that women in mid-life were being forgotten when it came to understanding health changes in mid-life. So, here we are – if your body shape is changing and you are struggling with weight gain and ‘nothing you are doing is working’, then have a read when you can. 

The Science Behind Your Changing Shape in Menopause

As we go into menopause our levels of oestrogen and progesterone naturally decline. However, what many women don’t realise (as I didn’t either), is that the master reproductive hormones in our pituitary gland actually ‘control’ menopause. These two master hormones, Luteinising Hormone (LH) and Follicle Stimulating Hormone (FSH), take longer to decline as we age, so in peri-menopause (the time before your periods cease in menopause) they are still trying to send chemical signals to the ovaries to keep producing oestrogen.

However, during peri-menopause the cells in your ovaries are dying-off. This is a natural part of your biological ageing but what it means is that there are less ovarian cells available to take the messages from your master-hormones. These chemical messages travel to other parts of your body, where you also have oestrogen receptor cells. This includes your heart muscles, your skin, your liver, your bones and your fat cells – and here’s the thing, women have the most fat cells around our belly, breasts, butt and thighs!

But there’s another reason that our shape changes during menopause too – we lose muscle size and density.

Our lovely muscle has oestrogen receptors too. Hence, they respond to our declining oestrogen environment. When we begin to lose muscle, our metabolism changes, because skeletal muscle has the most effect on our resting metabolic rate. Body-builders the world over know that muscle is important for metabolism and because the rate of muscle loss is highest for women during menopause, we don’t ‘burn’ as many calories as we used to. This muscle loss condition is called sarcopenia.

Muscle is needed so that we burn fat in our mighty mitochondrial cells.

One of the greatest effects on weight gain in menopause is our changing metabolism. Muscle tissue has the most effect on our resting metabolic rate. So, holding onto muscle as we go into menopause or doing strength activities and the right type of cardio activity is really important as we age but we can only influence muscle tissue, when we are sleeping, eating the right food and looking after liver health.

But there are other factors that impact menopause weight gain too. To improve our fat-burning capability when our hormones are against us, we need to achieve these things:

  • Sleep all night.
  • Improve liver health and function by reducing fatty liver.
  • Improve gut health, so nutrients are better absorbed.
  • Hold onto our muscle tone.
  • Manage our blood sugar levels and therefore, our insulin regulation.

Managing these factors is crucial for weight loss as we get older, especially sleeping all night.

Menopause has such an impact on our sleep patterns, but so too does our lifestyle, e.g. staying up late, using technology and eating the wrong foods at dinner-time. All of these factors impact on the production of our sleep hormone called melatonin. When melatonin levels are too low before bed-time, then we can experience more hot flushes, night sweats and as many of you will already know, you lie awake. But when this happens night after night, you lose your overnight fat-burning capability too.

Your liver and gall-bladder are also important for your weight loss during menopause. Turning around the health of your liver during menopause is important for fat-loss. The reason for this is because fats are broken-down by bile and bile is stored in our gall bladder. In the past this system has worked well for you – because you’ve had oestrogen. But as we lose oestrogen, we also produce less bile. On top of this is the fact that as women in our early 50’s, we’ve had a lot of different changes to our diet over the years which has possibly impacted on the health of our liver.

When inflammation is present in the liver, then it doesn’t absorb the crucial B-vitamins, which we need for our energy, and we don’t turn over the amino acids present in proteins. For many women putting on a lot of belly fat, or if you have the ‘hard-fat’ sitting around your abdomen, then please try to come on board into my ‘Transform Me’ weight loss programme, because I have researched how to turn around our liver health and improve the function of our gall-bladder.

It’s also why I don’t promote the high-fat, high protein diets that are popular in the fitness and nutrition industries at the moment. Many of these are not researched for our health during our menopause transition. Furthermore, if women are already on a slippery slope towards Type 2 diabetes, then this is caused by just one factor – too much fat in the liver and pancreas. (Taylor, 

Changing oestrogen levels during menopause, sarcopenia (muscle loss), liver health and insulin resistance are all connected. So too, is lack of sleep. 

When you aren’t sleeping, you aren’t getting enough secretion of two other important hormones necessary for retaining or building muscle which is why I reiterate that insomnia has the greatest impact on your weight gain in menopause.

Interrupted sleep during menopause throws our muscle-building and fat-burning capability out the door. When we aren’t sleeping properly, our insulin and cortisol levels stay high. This counteracts fat-burning and muscle repair. This is why the most powerful thing I do for you when you come on board into the MyMT™ Transform Me programme, is to get you sleeping all night.

If you aren’t sleeping well, then this is the first breakthrough you need to focus on for halting any further fat-gain as well as for helping you hold onto muscle.

for you to reverse or at least reduce the over-50’s condition of sarcopenia, you need to HALT any more fat-gain. To achieve this, you need to discover how to sleep all night, reduce the inflammation that has been building up over the decades in your liver and your joints and muscles as well as improve the health of your beautiful mitochondrial cells. These are located all over your body and they are the location of oxygen storage and the location of where fats and glucose are turned into energy molecules. When we lose muscle with sarcopenia, then we also lose the number and size of our mitochondrial cells.

When this happens we don’t burn fats as well, nor do we have as much energy. We begin to feel exhausted, and how hot flushes then increase as well. I know this, because that was me as well as numerous women who join me on the MyMT™ programme. 

I am so passionate about women following a progressive step-by-step process to turn around their weight and their health during menopause. Too many women are turning to crazy diets and exercise programmes when their hormones are changing, but what we need to is to restore the balancing act that our hormones require to pass through menopause. Yes, often this can mean menopause HRT, but this is between you and your Doctor. I’m interested in whether you also put into action, the evidenced lifestyle changes that go with this age and stage of  life too. The hormonal changes across the menopause years substantially contribute to increased abdominal obesity which leads to additional physical and psychological health changes, making it tough for women who need to perform at their best in mid-life. 

If we improve our sleep, lose excess abdominal fat, improve liver health, regulate blood sugar levels, reduce inflammation in our joints and hold onto muscle, then women’s healthy ageing research consistently reports that we are more resilient to the health changes that occur in older age.

Wendy Sweet, PhD/ Women’s Healthy Ageing Researcher & MyMT™ Founder & Coach/ Member: Australasian Society of Lifestyle Medicine. 


Davis S., Castelo-Branco C, Chedraui P., Lumsden M., Nappi R., Shah D., Villaseca P. (2012). Writing Group of the International Menopause Society for World Menopause Day 2012. Understanding weight gain at menopause. Climacteric, 15(5):419-29. doi: 10.3109/13697137.2012.707385.

Hall K., Guo J. (2017). Obesity Energetics: Body Weight Regulation and the Effects of Diet Composition. Gastroenterology, 152(7):1718-1727.e3. doi: 10.1053/j.gastro.2017.01.052. Epub 2017 Feb 11. PMID: 28193517; PMCID: PMC5568065.

Rezuş E., Burlui A., Cardoneanu A., Rezuş C., Codreanu C., Pârvu M., Rusu Zota G., Tamba BI. (2020). Inactivity and Skeletal Muscle Metabolism: A Vicious Cycle in Old Age. Int J Mol Sci. 2020 Jan 16;21(2):592. doi: 10.3390/ijms21020592. PMID: 31963330; PMCID: PMC7014434.

Taylor, R. (2020). Life without diabetes: The definitive guide to understanding and reversing type 2 diabetes. HarperOne Publ: UK


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