3 / How to Improve Your Metabolic Health After 45

You’ve built the foundations. Now we can go deeper. Not by doing more and more, but by understanding which metabolic levers actually matter.

By this point in our Weight & Metabolism journey, I hope something has changed in the way you think about your body. In the first article, we stopped treating midlife weight gain as simply a calorie problem and looked at what is happening underneath: changes in estrogen, muscle, visceral fat, insulin sensitivity and body composition.

In the second, we established the foundations: protect muscle, eat adequate protein, build better meals, move throughout the day, walk after meals and take sleep seriously.

If those foundations aren’t reasonably established yet, stay there for a while. You do not get extra metabolic points for making everything more complicated.

But perhaps you are already doing many of those things. You eat well. You walk. You exercise. You’re sleeping reasonably well. And still you feel as though something isn’t quite shifting.

This is where we start looking more closely at metabolic flexibility and the systems controlling how your body handles energy.

What does “metabolically healthy” actually mean?

Metabolic health isn’t simply being thin. It describes how effectively your body regulates and uses energy while maintaining healthy glucose regulation, blood pressure, blood lipids and fat distribution.

A metabolically healthy body should be able to deal with the arrival of glucose after a meal, store and use nutrients appropriately, access stored energy between meals and respond normally to hormones such as insulin. This ability to adapt to changing fuel availability is often described as metabolic flexibility.

You don’t need to be in ketosis to have it. You don’t need to fast for 20 hours. And you certainly don’t need to monitor every spoonful of food with a wearable device.

You want a body capable of adapting.

And one of the biggest obstacles to that flexibility is insulin resistance.

Insulin resistance is often the first metabolic lever I want to understand

We introduced insulin resistance earlier in this series, but now we need to look at it more closely.

When you eat carbohydrates, they are broken down into glucose to varying degrees and glucose enters your bloodstream. Your pancreas releases insulin, which helps glucose move into cells where it can be used or stored.

When muscle, liver and fat tissue become less responsive to insulin, the pancreas compensates by producing more of it. For quite some time, this can work. Your fasting glucose might still look perfectly respectable because your pancreas is working harder to keep it there.

This is one reason metabolic dysfunction doesn’t necessarily announce itself with one dramatically abnormal glucose result.

Over time, however, insulin resistance can contribute to prediabetes, type 2 diabetes, abnormal lipid metabolism, metabolic liver disease and increased cardiovascular risk.

The menopause transition can make this landscape more challenging because changes in estrogen, visceral adiposity and body composition can all interact with insulin sensitivity and cardiometabolic risk.

This is also why I don’t want to reduce insulin resistance to “You ate too much sugar.” The physiology is considerably more complicated.

Visceral fat isn’t just sitting there

This brings us back to the abdomen.

Subcutaneous fat is the fat you can pinch underneath your skin. Visceral fat is stored deeper in the abdominal cavity around internal organs. They are not metabolically identical.

Visceral adipose tissue is biologically active. Excess visceral fat is associated with altered adipokine signalling, inflammatory activity, insulin resistance and increased cardiometabolic risk.

This helps explain something women often find baffling: their weight may only have increased by a few kilograms, but their waist has changed dramatically.

That change matters.

It doesn’t mean you should become frightened of your stomach or start measuring your waist every morning. But waist circumference gives us useful information that the scales cannot.

The encouraging part is that visceral fat responds to intervention. Regular physical activity, resistance training, improved diet quality and appropriate fat loss can all help reduce abdominal and visceral adiposity.

So once again, the goal isn’t “How quickly can I lose five kilos?” A better question is: “How can I improve my body composition and reduce the metabolically harmful fat I am carrying?”

Your liver is doing far more than you probably realise

When people talk about metabolism, they often talk about the thyroid. They talk much less about the liver.

Yet your liver sits right in the middle of metabolic regulation. It stores and releases glucose, processes fats, participates in cholesterol metabolism and responds to insulin.

With insulin resistance, the liver can become less responsive to insulin’s signal to suppress glucose production. At the same time, disturbances in fat metabolism can contribute to accumulation of fat within the liver.

This is one pathway towards metabolic dysfunction-associated steatotic liver disease, or MASLD, previously commonly called non-alcoholic fatty liver disease.

MASLD is strongly associated with insulin resistance and other cardiometabolic abnormalities, and you can have it without drinking excessive alcohol or feeling ill. In fact, there may be no obvious symptoms at all.

This is one reason markers such as ALT, AST and GGT can form part of a broader metabolic assessment, although it is important to understand that normal liver enzymes do not completely rule out excess liver fat.

Again, think systems. Your waist, glucose, triglycerides, insulin and liver are not living separate lives.

Now let’s talk about carbohydrates without starting a war

Few areas of nutrition create quite as much unnecessary drama as carbohydrates.

One camp tells women after menopause to eliminate them. Another tells them carbohydrate restriction is completely unnecessary. Neither blanket statement is particularly useful.

Carbohydrate tolerance varies between individuals and can be influenced by activity, muscle mass, insulin sensitivity, total energy intake and the type and quantity of carbohydrate eaten.

A bowl of lentils, an apple, a plate of vegetables and a packet of biscuits are all technically carbohydrate-containing foods. Metabolically and nutritionally, they are clearly not interchangeable.

So rather than asking, “Should women over 45 eat carbs?”, I want you asking, “Which carbohydrates, how much, in what context, and what is my metabolic health?”

For most women, I would start with minimally processed carbohydrate sources such as vegetables, legumes, fruit, whole grains where tolerated and appropriate portions of starchy foods rather than automatically removing an entire macronutrient.

Combining carbohydrate with protein, fibre and fat can also influence digestion, satiety and the resulting glucose response compared with eating a refined carbohydrate food on its own.

And remember one of our simplest metabolic tools from the previous article: use your muscles after eating.

A short walk is considerably less exciting than a glucose-hacking supplement. It also happens to be useful.

Do you need to avoid glucose spikes?

This is another area where social media has taken a useful physiological concept and occasionally turned it into something rather strange.

Blood glucose is supposed to rise after you eat carbohydrate. That isn’t metabolic failure. It is normal physiology.

What concerns us is inappropriate or prolonged glucose elevation in the context of impaired glucose regulation, rather than the mere existence of a rise after eating.

Trying to flatten every normal glucose response in a healthy person can turn eating into an unnecessary biochemical surveillance programme. I don’t want you afraid of a banana because your glucose might rise. I want to know what your overall glucose regulation looks like.

What is your fasting glucose? Your HbA1c? Do you have risk factors for insulin resistance? What are your triglycerides doing? What is happening around your waist? What is your blood pressure? How active are you? What is your family history?

Patterns matter more than one spike after lunch.

Should you use a continuous glucose monitor?

Continuous glucose monitors can be extraordinarily useful medical devices, particularly for people living with diabetes. They may also sometimes provide useful information about individual glucose responses in people without diabetes.

But I don’t believe every healthy midlife woman needs one.

If wearing a CGM helps someone understand how meals, exercise, sleep and other factors influence her glucose, there may be educational value. If it makes her frightened of food and obsessed with keeping a perfectly flat glucose line, we have missed the point.

More data isn’t automatically better health.

Use technology when it answers a useful question. Don’t create a question because you bought the technology.

What about intermittent fasting?

Now we can revisit fasting.

There is genuine research interest in time-restricted eating and intermittent fasting, and these approaches can be useful for some people. But we need to separate the intervention from the mythology surrounding it.

Intermittent fasting is not magic.

One reason it can work is extremely practical: shortening the eating window can reduce opportunities to eat and therefore help some people reduce overall energy intake. Meal timing may also interact with circadian biology and metabolic regulation, with earlier eating patterns potentially offering advantages over concentrating large amounts of food late at night.

But that does not mean every woman over 45 needs to fast for 16, 18 or 20 hours to “reset her metabolism.”

Your response matters.

If a 14-hour overnight fast naturally stops late-night grazing, feels easy and allows you to meet your protein, energy and nutritional needs during the day, fine.

If an 18-hour fast leaves you tired, irritable, unable to train properly and eating everything in sight between 6pm and bedtime, it is not superior simply because the fasting window was longer.

The question isn’t “How long can I fast?”

It is “Does this eating pattern improve my health and make my life easier?”

Meal timing matters, but probably less than Instagram suggests

Human metabolism follows circadian rhythms. We aren’t metabolically identical at 8am and midnight.

Insulin sensitivity and glucose tolerance show circadian variation, and routinely concentrating a large proportion of daily energy intake very late in the day may be less favourable metabolically for some people.

This does not mean dinner at 8pm destroys your metabolism.

It means that if much of your eating happens late at night, particularly if you have already eaten adequately throughout the day, meal timing may be one useful area to examine.

For many women, a simple overnight period without food of around 12 hours can be a perfectly sensible starting point. Finish dinner, close the kitchen, go to bed and eat again the following morning.

It doesn’t require an app.

And then there is cortisol

Poor cortisol has been blamed for virtually everything that happens to women after 40.

Your belly? Cortisol. Can’t lose weight? Cortisol. Woke up grumpy? Definitely cortisol.

Let’s put it back into physiological context.

Cortisol is an essential glucocorticoid hormone involved in the stress response, glucose regulation, immune function and circadian rhythm. You need it.

Chronic psychological stress, however, can influence sleep, appetite, food choices, physical activity and metabolic regulation. Stress physiology can therefore contribute to the metabolic picture.

But that does not mean every woman struggling with weight has “cortisol belly,” nor does it mean you need an expensive cortisol supplement.

Often the most useful stress interventions are spectacularly unmarketable: adequate sleep, daylight, movement, exercise, social connection, boundaries, relaxation and, where possible, dealing with the actual source of chronic stress.

We don’t need to “eliminate cortisol.” We need a stress response capable of turning on when necessary and settling again when the threat has passed.

Inflammation is part of the picture too

Chronic low-grade inflammation and metabolic dysfunction often travel together.

Expanding visceral adipose tissue can alter the production of inflammatory signalling molecules, while insulin resistance, poor diet quality, inactivity and metabolic disease can contribute further to the inflammatory environment.

This relationship works in more than one direction, which is another reason I dislike single-cause explanations.

And you don’t need an exotic anti-inflammatory detox.

The same boringly effective things keep appearing: regular exercise, adequate sleep, fibre-rich plant foods, appropriate body-fat reduction where needed, omega-3-rich foods, not smoking and limiting excessive alcohol.

There is an important lesson here. The deeper we go into metabolism, the more often we arrive back at the foundations.

What about supplements?

Supplements can be useful when there is a specific reason for taking them.

Correcting a vitamin D deficiency makes sense. Treating iron deficiency makes sense. Omega-3 supplementation may be useful in an appropriate clinical context. Magnesium may be useful where there is an indication for it.

Taking six bottles labelled “Metabolic Burn”, “Glucose Control” and “Cortisol Balance” because your metabolism feels slow is not a metabolic strategy.

In functional medicine, supplements should come after the question, not before it.

What are we trying to change? Do we have evidence that it needs changing? Is there a food or lifestyle intervention that addresses it? Is there evidence the supplement helps? Could it interact with medication or another condition?

That is a very different approach from simply buying everything in the menopause aisle.

How do you know which metabolic lever YOU need?

This is where individualisation actually matters.

If you have very little muscle and don’t strength train, your priority probably isn’t a longer fasting window. If you sleep five hours a night, I wouldn’t begin by worrying about whether blueberries create a glucose spike. If your diet is dominated by ultra-processed foods, we don’t need nutrigenomic testing to identify our first move.

If your waist circumference is increasing, triglycerides are elevated, blood pressure is rising and glucose regulation is deteriorating, I want to look much more closely at insulin resistance and cardiometabolic risk.

And if you are doing most things well but your weight has changed dramatically and you are exhausted, cold, constipated or experiencing other symptoms suggestive of thyroid dysfunction, then investigation makes considerably more sense than simply telling you to try harder.

The more specific the problem becomes, the more specific the intervention can become.

That is the point of personalised care. Not complexity for complexity’s sake.

A sensible metabolic hierarchy

If I were sitting opposite you and we were trying to decide what comes next, I would work through the problem in roughly this order.

First, are the foundations genuinely in place? Are you eating adequate protein and nutrient-dense food, resistance training, moving regularly and getting enough good-quality sleep?

Next, what does your body composition appear to be doing? Are you losing muscle? Is your waist circumference increasing? Is excess visceral fat becoming part of the picture?

Then I would look at your cardiometabolic markers. Is glucose regulation changing? What are triglycerides and HDL doing? What is your blood pressure? Are there signs that liver metabolism needs attention?

Only after understanding that picture would I start asking whether more specific strategies such as adjusting carbohydrate quantity or timing, time-restricted eating or targeted supplementation are actually useful.

This is the difference between following a metabolic trend and addressing your metabolic problem.

And please give your body time

Metabolism is not a 21-day project.

HbA1c itself gives us information about average glucose exposure over roughly the previous two to three months. Muscle takes time to build. Visceral fat doesn’t disappear because you had three good breakfasts. Sleep habits take time to establish. Insulin sensitivity responds to what you repeatedly do.

So stop assessing your metabolic health every morning.

Give the physiology time to respond.

I would much rather see three months of reasonably consistent habits than three weeks of metabolic perfection followed by complete exhaustion.

Consistency is not the boring alternative to optimisation. Consistency is what makes optimisation work.

Which biomarkers I recommend checking

At this stage, testing becomes more useful because we are no longer simply asking, “Am I gaining weight?” We are asking, “What is happening metabolically?”

For glucose regulation, I commonly want to see fasting glucose and HbA1c, while fasting insulin may provide additional information in an appropriate clinical context. These numbers should be interpreted together rather than turning any single result into a diagnosis.

For cardiovascular and lipid metabolism, useful markers include triglycerides, HDL-C, LDL-C and non-HDL cholesterol, with ApoB providing information about atherogenic lipoprotein particle burden. Lp(a) is largely genetically determined and is worth discussing as a measurement at least once in adulthood as part of cardiovascular risk assessment.

For liver health, ALT, AST and GGT are useful starting markers, particularly where central adiposity, insulin resistance or MASLD is suspected, although normal liver enzymes do not necessarily exclude excess liver fat.

Blood pressure and waist circumference belong in this metabolic assessment too, despite requiring no blood test at all.

Depending on symptoms and history, thyroid assessment usually begins with TSH and free T4, with additional testing guided by the clinical picture rather than ordering every thyroid marker routinely.

hs-CRP may sometimes provide additional information about systemic inflammation and cardiovascular risk, but because it is nonspecific, an elevated result always needs context.

And this brings us perfectly to the final article in this series. Because knowing which tests to order is only half the job. You also need to understand what the results are telling you.

Your next step

You now understand the metabolic system much more deeply. You know why muscle matters, why visceral fat matters, how insulin resistance can develop quietly, why your liver belongs in the conversation, why carbohydrates aren’t automatically the enemy, why fasting is a tool rather than a requirement, and why more data and more supplements aren’t necessarily better.

Now we investigate.

In the final article in this Weight & Metabolism series, we’re going to put the pieces together: which blood tests are worth checking, what they actually tell us, which patterns can suggest metabolic dysfunction and when your “stubborn weight” deserves proper medical investigation.

Read next: The Blood Tests That Tell You What Is Really Happening With Your Metabolism

You can also explore more related articles, free and paid resources, my book and programmes in the Weight & Metabolism section of Feel Good Menopause.