Insulin: the silent key to storage

Insulin is released by the pancreas as soon as a carbohydrate (and to a lesser extent a protein) enters the blood. Its main function: store glucose in muscle, liver and fat cells. As long as it is high, lipolysis (fat release) is blocked.

Three or four carbohydrate meals a day, plus sugary snacks and sodas, keep insulin elevated almost continuously. The body is in storage mode 18 to 20 hours out of 24. Losing weight becomes mechanically difficult, regardless of calories.

Over-stimulated, cells reduce their sensitivity to insulin signals. The pancreas compensates by producing more. Circulating insulin rises, so does glucose. This vicious cycle defines insulin resistance, the silent prelude to type 2 diabetes.

Visceral adipose tissue, especially around the liver, worsens the picture: it releases inflammatory cytokines that further impair insulin signalling. A waist circumference over 88 cm (women) or 102 cm (men) is a recognised clinical marker.

Not all carbohydrates are equal. The glycaemic index measures the speed at which a food raises blood glucose. The glycaemic load also integrates the quantity. White bread (GI 75) causes a sharp peak; lentils (GI 30) a smooth, prolonged rise.

The DIETFITS trial (JAMA 2018), re-analysed in Cell Metabolism (2024), confirms that low-glycaemic-load diets produce greater weight loss than high-glycaemic-load hypocaloric diets at equivalent calories.

Eating vegetables and proteins before carbohydrates reduces the postprandial glucose peak by 30 to 40% (Shukla et al., BMJ Open Diabetes Research & Care, 2023). The mechanism: fibres and proteins slow gastric emptying, delay glucose absorption, and increase GLP-1 secretion.

It's free, immediate, and works everywhere. A salad starter followed by starches at the end — or simply an egg or a piece of cheese before the bread — measurably changes the insulin response.

Spacing meals lets insulin fall and reopens the lipolysis window. The 16/8 protocol (8 hours of eating, 16 hours of fasting, sleep included) is best studied. Documented benefits: lower fasting insulin, improved insulin sensitivity, visceral fat loss (Nature Reviews Endocrinology, 2023).

Real contraindications: pregnancy, breastfeeding, history of eating disorders, adrenal insufficiency, insulin-treated diabetes without medical supervision. This is not trivial.