So… what is metabolism, really?

Forget the memes. In simple language:

Metabolism is everything your body does to turn food into energy and keep you alive.

Breathing, thinking, repairing cells, digesting food, keeping you warm, moving your body, growing hair – all of that.

When people say “my metabolism is slow,” they usually mean:

“I feel like I gain weight easily and lose it painfully slowly.”

That feeling is real.
The explanation is usually… different from what the diet industry sells.

The 4 pillars of your daily energy burn

Your total daily energy use (TDEE, if we’re being nerdy) comes from four buckets:

1. Basal Metabolic Rate (BMR)

This is what your body burns doing absolutely nothing – lying in bed, simply staying alive.

Heart beating. Lungs working. Brain running Windows 95.

For most people, this is 60–70% of daily energy use. It’s huge.

What affects BMR the most?

• Body size (bigger bodies burn more, not less)
• Amount of muscle vs fat
• Genetics
• Hormones (thyroid, sex hormones, etc.)

Spoiler: your BMR probably isn’t dramatically lower than everyone else’s at your height/weight – we’re talking differences of maybe a few hundred calories, not thousands.

2. NEAT (Non-Exercise Activity Thermogenesis)

Awful name. Important thing.

This is all the movement that isn’t “official exercise”:

• walking to the bus
• standing vs sitting
• fidgeting
• cleaning, cooking, carrying groceries

NEAT can vary wildly between people.
Two humans with the same BMR and workouts can burn hundreds of calories different per day just by how much they move in daily life.

3. Exercise Activity

Your workouts. Runs, strength training, classes, sports.

Important for strength, fitness, mood, long-term health.
But as a % of total energy expenditure? Smaller than most people think.

A 40-minute workout does not cancel out 14 hours of sitting completely still. Sorry, fitness marketing.

4. Thermic Effect of Food (TEF)

Energy your body uses to digest and process food.

Protein has the highest TEF (your body spends more energy breaking it down), carbs are in the middle, fats are lowest. Another quiet reason protein helps with weight management.

“My metabolism is damaged.” Is that a thing?

Short answer: not in the way Instagram makes it sound.

Your metabolism is not a fragile crystal that shatters because you ate 1200 calories for a month.

What is true:

• Weight loss reduces energy needs.
  Smaller body = fewer calories required. That’s physics, not punishment.
• Crash dieting can temporarily lower metabolism more than expected.
  Your body adapts. You move less without noticing, hormones like leptin/ghrelin change, your NEAT drops. You feel tired. You burn a bit less.
• Extreme cycles of dieting and regain can make weight regulation harder.
  Not because you’re “ruined”, but because your body learns to defend against big swings.

But you do not permanently destroy your metabolism with one bad diet.
There is no “point of no return” where you’re doomed forever.

Age, hormones, and the “I used to eat anything” myth

Yes, metabolism changes with age.
No, it doesn’t fall off a cliff at 30.

What actually happens for many of us:

• We lose muscle if we don’t use it.
• We sit more and move less.
• Sleep gets worse, stress goes up.
• We can afford more food, snacks, drinks than in our broke student years.

All of that lowers daily energy use a little and increases intake a lot.

Hormones matter too:

• Thyroid issues can affect metabolism.
• Menopause changes where fat is stored and how hungry we feel.
• Chronic stress and poor sleep mess with hunger signals.

If you suspect medical reasons (sudden weight change, extreme fatigue, cold intolerance, hair loss) – that’s doctor territory, not “drink more water” territory.

What actually boosts metabolism (boring but real)

1. Building and keeping muscle

Muscle is metabolically active tissue.
It doesn’t turn you into a furnace, but it does:

• raise your BMR a bit,
• improve insulin sensitivity,
• make everyday movement easier (so NEAT goes up too).

Translation: strength training 2–3× per week is one of the most honest “metabolism boosters” out there.

Not “fat-burning cardio” for 2 hours.
Simple, progressive strength.

2. Moving more in everyday life (NEAT)

You don’t have to live at the gym.
But you do want to live less in the chair.

Ideas that don’t require you to become a totally new person:

• 5–10 minute walks after meals
• standing up for calls
• parking a bit farther
• doing one “housework block” per day instead of all at once on weekends

NEAT is sneaky. It doesn’t feel like “working out”, but it adds up like compound interest.

3. Eating enough protein

No, protein is not a magic fat burner.
But it:

• helps maintain or build muscle, especially in a deficit;
• has higher TEF (your body burns more processing it);
• increases satiety, which reduces “graze all day” behaviour.

Aim for a decent source of protein in each meal. Not perfect grams. Just visible, obvious protein.

4. Not living in permanent diet mode

Chronically eating way too little:

• makes you tired and cold
• drops NEAT (you subconsciously move less)
• wrecks your mood and sleep

All of which ironically make fat loss harder.

Sometimes the most “metabolism-friendly” thing you can do is… eat a bit more, build muscle, let your nervous system calm down, then go back into a moderate deficit later.

What does not meaningfully boost metabolism

Let’s save you some money and frustration.

• Detox teas
• “Metabolism-boosting” supplements with green tea and caffeine
• Tiny “fat-burning” foods (lemon water, ginger shots, apple cider vinegar)
• Doing HIIT every single day
• Freezing yourself on purpose “to burn more calories”

Can these things change energy burn by a few percent here and there? Sometimes.
Can they compete with muscle, NEAT, and overall intake? Not really.

They’re sprinkles. The basics are the cake.

So if I want fat loss, where does metabolism fit in?

You still need a calorie deficit for fat loss.
Metabolism doesn’t cancel physics.

But understanding metabolism changes how you create that deficit:

• You don’t starve yourself. You create a moderate deficit.
• You protect muscle with strength training and protein.
• You keep NEAT alive by not exhausting yourself with extreme cardio.
• You respect sleep and stress because they directly influence hunger and energy.

Instead of asking, “How can I hack my metabolism?”
Try: “How can I make my metabolism’s job easier?”

Quick Metabolism Myths vs Reality

• “I barely eat and still don’t lose. My metabolism is dead.”
  Most people under-report intake (because we’re human, not liars) and forget liquid calories, snacks, bites, weekends. Also: sitting 10–12 hours a day quietly lowers burn. Track gently for a week, without judgment, and it usually makes more sense.
• “Carbs slow your metabolism.”
  No. Overeating anything can lead to weight gain. Carbs themselves don’t “shut down” metabolism. In fact, some carbs (especially whole grains) support thyroid function and training performance.
• “Eating after 6 p.m. kills metabolism.”
  Your metabolism does not clock out at 18:01. Late-night eating can be an issue because we tend to snack mindlessly, not because calories suddenly count more.

The SashaHealthy bottom line

Your metabolism is not your enemy.
It’s not lazy. It’s not broken. It’s not sitting there plotting against your jeans.

It’s a dynamic system trying very hard to keep you alive in a world of:

• constant sitting,
• constant stress,
• constant access to hyper-palatable food.

When you:

• move more in normal, unsexy ways,
• lift something heavier than your phone a few times a week,
• eat enough (especially enough protein),
• and stop abusing crash diets,

you’re already doing 90% of what people mean when they say they want to “fix their metabolism”.

Science-backed. Human-proven.
No magic powder required.