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Metabolism

How Your Metabolism Actually Works

Weight is ultimately a metabolic story: energy intake, energy expenditure, hormonal signalling, and how the body adapts under a calorie deficit. These guides cover what GLP-1 medications do to body composition, why protein and resistance training matter, and how to think about long-term metabolic health beyond the scale.

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Metabolism

Adaptive Thermogenesis: Why Your Metabolism Slows When You Diet

Lose 10% of your body weight and your resting metabolic rate falls by more than the smaller body would predict. That gap has a name — and three decades of research mapping how it works.

10 min read·Updated May 2026
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Metabolism

Is 'Metabolic Damage' Real? What the Research Actually Says

Adaptive thermogenesis is documented and persistent. 'Permanent metabolic damage' is mostly myth. The distinction matters because it changes what someone with a long dieting history can reasonably expect.

9 min read·Updated May 2026
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Metabolism

Why 'Eat Less, Move More' Doesn't Work for Most People

The calories-in, calories-out model isn't wrong — it's dangerously incomplete. Here's what actually happens to your metabolism, hunger, and energy when you try to follow it.

8 min read·Updated May 2026
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Metabolism

Energy Balance and Weight Regulation: Beyond Calories In, Calories Out

The 'calories in, calories out' model is technically correct but practically incomplete. Your body actively adjusts both sides of the equation in response to what you eat — and that changes everything.

8 min read·Updated May 2026
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Metabolism

Metabolic Adaptation: Why Your Body Fights Back Against Weight Loss

During calorie restriction, the body systematically reduces energy expenditure — often by more than the lost tissue accounts for. This adaptive thermogenesis is a primary reason weight loss plateaus and rebounds.

8 min read·Updated May 2026
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Metabolism

Is Slow Metabolism Real? What the Research Actually Shows

Most people attribute weight gain to a slow metabolism. The science is more nuanced — true metabolic rate differences between individuals are smaller than commonly believed, but they're real.

9 min read·Updated May 2026
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Metabolism

Insulin Resistance Explained: Causes, Effects, and What to Do

Insulin resistance is one of the most common metabolic dysfunctions — and one of the least understood by people who have it. Here's what the science shows about causes, consequences, and interventions.

10 min read·Updated May 2026
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Metabolism

Fatigue and Dehydration on a GLP-1: An Underrated Pair

Tiredness on a GLP-1 is often blamed on the drug itself — when the real culprits are under-eating and not drinking enough. Here's how to tell the difference.

6 min read·Updated April 2026
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Metabolism

Preserving Muscle While You Lose Weight on a GLP-1

Rapid weight loss without a plan costs you muscle. Two levers — resistance training and protein — protect the body composition you actually want.

7 min read·Updated April 2026
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