How Does Semaglutide Work?

GLP-1 medications work for weight loss due to several mechanisms that affect appetite, digestion, and metabolism. Here's a breakdown of how they contribute to weight loss:

1. Suppress Appetite

GLP-1 (glucagon-like peptide-1) receptors in the brain, particularly in areas like the hypothalamus, help regulate hunger. When GLP-1 medications are used, they activate these receptors, reducing the sensation of hunger. This makes people feel full (or "satiated") more quickly and helps them eat less overall.

2. Slow Gastric Emptying

GLP-1 medications slow down the rate at which food leaves the stomach and enters the small intestine. This prolongs the feeling of fullness after meals, helping to reduce overall calorie intake. When food stays in the stomach longer, hunger signals are delayed, and people are less likely to snack or overeat.

3. Influence Insulin and Glucagon

GLP-1 increases insulin secretion when blood sugar levels are high and inhibits the release of glucagon, a hormone that raises blood sugar levels. By improving insulin sensitivity and lowering glucagon, these medications help manage blood sugar, which also contributes to weight regulation. Stable blood sugar levels can reduce cravings for high-calorie, high-sugar foods.

4. Modulate Reward Pathways

GLP-1 may affect the brain's reward pathways, specifically those linked to eating behavior and the pleasure derived from food. By modulating these pathways, people may feel less driven to eat for emotional reasons or for the sheer pleasure of eating especially high-calorie or sugary foods.

5. Promote Fat Loss Over Lean Muscle Loss

Some studies suggest that weight loss with GLP-1 medications primarily involves fat loss rather than lean muscle mass. This is important for maintaining metabolic health and preventing the negative effects associated with losing muscle while dieting.

6. Reduced Caloric Intake

Because GLP-1 medications reduce hunger and make people feel fuller with less food, they lead to a natural reduction in calorie intake, which results in gradual weight loss over time.