01/04/2026
If your metabolism feels “broken”… it’s usually not a willpower problem.
It’s a systems problem.
Here are the most researched drivers of metabolic dysfunction — and what to actually do about them:
1. Chronic under-eating
→ Lowers thyroid output + resting metabolic rate
Action: Eat enough protein (aim ~1.6–2.2g/kg) + stop living in a calorie deficit year-round
2. Low muscle mass
→ Muscle = your primary glucose sink
Action: Strength train 2–3x/week + prioritise progressive overload
3. Insulin resistance
→ Drives fat storage + energy crashes
Action: Build meals around protein + whole carbs, walk after meals, reduce ultra-processed foods
4. Poor sleep (even 1–2 nights)
→ Increases hunger hormones + reduces insulin sensitivity
Action: Morning sunlight, consistent sleep/wake time, reduce blue light at night
5. Chronic stress / high cortisol
→ Signals “survival mode” → slows fat loss
Action: Daily down-regulation (walks, breathwork, less high-intensity training if burnt out)
6. Micronutrient deficiencies
→ Thyroid, mitochondria + hormone production suffer
Action: Prioritise whole foods: red meat, eggs, fruit, root veg + test when needed
7. Gut dysfunction (dysbiosis / endotoxin)
→ Inflammation → worsens insulin resistance
Action: Remove irritants, support digestion, consider targeted testing if stuck
8. Environmental toxin load
→ Endocrine disruption (hormones + metabolism)
Action: Reduce plastics, fragrances, non-stick cookware, ultra-processed foods
9. Circadian disruption
→ Metabolism is time-dependent, not just calorie-dependent
Action: Get sunlight early, eat at consistent times, limit late-night eating
10. Adaptive dieting history
→ Repeated restriction → metabolic adaptation
Action: Reverse diet, rebuild intake slowly, focus on restoring output (movement + muscle)
Your metabolism isn’t broken.
It’s adapting to the environment you’re giving it.
Fix the inputs → the output follows.
If you want help identifying your biggest blockers,
comment ROADMAP and I’ll send you the Functional Testing Roadmap.