Metabolic Health
What Is Insulin Resistance and How Does It Cause Weight Gain?
Insulin resistance makes cells less responsive to insulin, forcing the pancreas to produce more. The result is elevated...
If you have ever tried to lose weight and succeeded only to regain it — you are in the majority. Long-term statistics on weight loss maintenance show that most people who lose weight regain it within two to five years. This is not a failure of character. It reflects a biological system specifically designed to resist weight loss and restore previous weight.
Understanding why makes the appropriate interventions obvious.
The Body Defends Its Weight
The hypothalamus maintains a "defended weight" — a set point around which hormonal and metabolic systems actively work to keep body weight stable. This system evolved in environments of food scarcity, where resisting weight loss had survival value.
When weight falls below the defended set point, the body responds with a coordinated biological counter-attack:
Hunger hormones increase: Ghrelin (the hunger hormone) rises dramatically and stays elevated — not just until weight is restored but for years afterward in some studies. The famous "Biggest Loser" follow-up study (Fothergill et al., 2016) found contestants' ghrelin levels remained elevated six years after the competition ended.
Satiety hormones decrease: GLP-1, PYY, and leptin — the signals that create fullness — all fall when weight is lost. The fullness signal becomes weaker precisely when you most need it to be strong.
Metabolic rate drops: Resting metabolic rate (RMR) falls beyond what is explained by having less body mass to maintain. In the Biggest Loser study, RMR was 500 kcal/day lower than expected for their weight — years after the competition. This means formerly obese individuals must eat 500 kcal less per day than a person who was never overweight at the same body weight.
The Set Point Problem
The defended weight set point is not fixed — it can shift upward relatively easily (through chronic overeating and inactivity) but is highly resistant to downward movement. This asymmetry reflects the evolutionary environment: gaining fat during abundance to survive famine was adaptive. Losing fat to stay lean had no survival advantage when food was scarce.
In modern environments, this asymmetry becomes a pathological disadvantage. The same system that protected our ancestors from starvation now makes obesity chronic and self-reinforcing.
The Cognitive and Behavioural Overlay
Beyond the hormonal biology, food environments add cognitive challenges that compound biological difficulty:
- Ultra-processed food is engineered to produce eating beyond satiety by exploiting the brain's reward circuitry
- Stress increases cortisol, which drives visceral fat deposition and carbohydrate cravings
- Sleep deprivation (endemic in modern life) raises ghrelin and lowers leptin — simulating the hormonal environment of fasting
- Social eating norms make consistent dietary behaviour socially challenging
These factors are not excuses — they are documented biological and environmental realities.
What This Means for Treatment
This biological understanding explains why calorie restriction alone has a high failure rate for sustained weight loss. It is not that people lack willpower — it is that they are fighting their own biology with inadequate tools.
Effective interventions address the underlying biology:
- GLP-1 pathway support restores the satiety signal (GLP-1) that falls during weight loss, directly counteracting the biological drive to regain
- Resistance training partially counteracts metabolic rate reduction by preserving lean mass
- High-protein diet provides the strongest non-pharmacological satiety signal available
METASLIM specifically addresses the hormonal driver — GLP-1 depletion — through sublingual drops, while the physician-guided 8-week program provides the dietary and behavioural framework to sustain the biological support.