Oct 14

Oct 14 Rethinking Metabolism ~ A New Way to Understand Weight & Health

Much health advice still centres around the idea that metabolism is something we can control through personal discipline: eat less, move more, and the body will simply burn more fat. However, modern science tells a different story - metabolism isn't driven purely by conscious choice - it's shaped by genetics, hormones, sleep, stress, food quality, muscle mass, inflammation and even our microbiome.

We also tend to judge our metabolic health by the number we see on the scales. In reality, it’s much broader than weight and is closely linked to long-term markers like blood glucose, cholesterol, blood pressure and cardiovascular wellbeing.

In this blog I draw on the latest science to offer a fresh way to think about the functioning of our metabolisms, why so many people feel they’re “failing” when the truth is far more complex, and how we can support ourselves in ways that feel nourishing rather than punishing.

What we used to believe

Most of us grew up hearing the same message: “To lose weight, just eat less and move more.” It sounded so sensible, logical and neat! And yet if it were truly that simple then dieting would not be a multi-billion-pound industry and long-term weight regain wouldn’t be the norm for 80-95% of people.

The traditional model views metabolism like basic maths:
Food in - movement out = fat gain/loss

In other words: Conscious behaviour → determines energy intake/expenditure → determines fatness → determines metabolic health

Change the numbers and you can control your weight which then determines your health:
Eat less/move more → lose fat → health improves

In this view, metabolism is something we can control with discipline. Simple - except that lived experience suggests otherwise. If you have ever tried dieting and found yourself hungrier, thinking about food constantly or regaining weight despite effort, you’ve met the flaw in this model.

A more accurate picture

Newer science looks at metabolism as a complex, dynamic web rather than as a balance sheet.

Our individual level of metabolic efficiency (how well the body converts, stores and uses energy) is shaped by genetics alongside our environment, hormones, sleep, stress, nourishment, muscle mass, microbiome, medication, trauma history and more.

Essentially:
Genes and other factors → influence metabolic regulation → influences cardiometabolic health outcomes AND influences hunger signals, reward, cravings and appetite → which then influence eating behaviour and weight outcomes

In this model, our genetics and biology help set the blueprint for metabolism and directly play a role in our health outcomes AND they directly influence our eating behaviour - meaning the body powerfully drives most of eating behaviour unconsciously.

Whilst we may have some degree of control over some of the conditions in which our metabolism operates, and some degree of control over how we eat and our energy expenditure through movement, in reality there is much more at play in our metabolic health than is in our conscious control.

As you can see, this model also turns the ‘weight-first’ approach on its head. What we now understand is that when the metabolism is under strain this can lead to fat gain, not the other way around. Fatness may be seen as a symptom, not always the cause.

And importantly, all body fat isn’t inherently harmful. Our metabolism is one of the systems that helps defend a person's natural set-point weight range - the range of body fat their biology is wired to maintain. Body fat only tends to become problematic and feed metabolic challenges when fat cells are inflamed, overfilled or metabolically stressed. This is more likely with excess visceral or ectopic fat or when the body is under metabolic strain - for example during chronic stress or sleep disruption, long-term under-nourishment or low muscle mass.

So if your intention is improve your health, pursuing a lower weight through dieting without considering how you are actually supporting your metabolism, is a little like repainting a house without checking the foundations first.

So what ACTUALLY is metabolism?

You may already have a sense that metabolism is so much more than weight or calories but before we go further, I want to offer a clear definition of what metabolism actually is.

Metabolism is the body’s ongoing biochemical ‘orchestra’ - a set of chemical reactions and the constant process of turning food into energy, repairing tissues, building hormones, fuelling thought, movement and life. Two processes work together moment-to-moment:

Catabolism: breaking down fuel for energy
Anabolism: building, repairing and maintaining the body

When metabolism is running smoothly, the body manages fuel efficiently: glucose moves in and out of the bloodstream as needed, cholesterol is transported and recycled, inflammation stays low, and blood vessels remain flexible and well-nourished.

But when metabolism is under strain, we often see early shifts in markers related to how well the body is processing, transporting and using energy such as:

rising blood glucose or HbA1c (reduced insulin sensitivity)
changes in cholesterol patterns (especially higher triglycerides or LDL, lower HDL)
increased blood pressure (blood vessels under greater metabolic stress)
higher visceral fat (more inflammatory signalling)

We may notice changes in energy, mood and appetite regulation too. And collectively these markers give us a much more meaningful picture of our health - both metabolic and cardiovascular - than weight alone ever could.

If REDUCING FAT OR THE NUMBER ON THE SCALES isn’t the goal, what is?

If our aim is supporting more efficient metabolic function or improving cardiovascular health, then chasing fat loss misses the point. A more helpful focus is to support how the body functions in the areas we can influence. Some ways we can do this include:

eating enough (especially after years of restrictive eating or dieting)
having balanced meals that help keep blood glucose within a healthy range and include protein for satiety and muscle repair
building appetite awareness so we can respect our own hunger and fullness cues
building and maintaining muscle strength
regulating stress and nervous system load
prioritising sleep and circadian rhythm
supporting gut health and microbial diversity
nurturing emotional wellbeing and a kind relationship with eating

When these foundations improve, metabolic markers can often follow - with or without weight change. Over time, the body tends to settle at a weight that feels safe, nourished and sustainable.

MY CONCLUSIONS

The growing understanding of metabolic science is perhaps one of the most hopeful shifts we’ve seen in nutrition. Whilst the concept of energy balance still has relevance, this marks an important move away from the overly simplistic old model of it that blamed individuals for their weight and assumed it was entirely within personal control.

We now recognise that multiple factors play into our unique energy balance, that weight is not simply a choice, and that any cardiometabolic health challenges we experience can’t be reduced to a lack of effort. Instead they may a sign that your body is responding to a complex mix of genetic biology and environment.

This model also helps us understand why trying to control weight directly doesn’t always deliver the health outcomes people hope for.

Whilst it can be difficult - but also liberating - to accept that our metabolism and ultimate health outcomes aren’t fully within our personal control, there are still weight-neutral, sustainable and evidence-based steps we can take to support our cardiometablic health. These are steps that work with your biology rather than against it - and include focusing on regular nourishment, rest, strength building, blood sugar balance, stress regulation and food peace, rather than restriction.

Take a nourishing step forward today

Are worries about food, weight or overeating draining your time, energy and peace of mind? Are you struggling with low mood, persistent food cravings, poor gut health or digestive challenges?

Old mindsets and habits can be hard to shift on your own. If you are looking to find peace with food and your body, and eat with more confidence and ease, I can help you.

Please check out my private programmes here, or book an exploratory chat to find out more.

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