GLP-1 receptor agonists are a class of medications used to treat type 2 diabetes mellitus. However, they have also been found to be effective in promoting weight loss. The exact mechanism by which GLP-1 receptor agonists promote weight loss is not fully understood, but it is thought to be due to several factors.

One mechanism is through their effect on appetite. GLP-1 receptor agonists slow down gastric emptying, which means food stays in the stomach for longer periods of time, leading to feelings of fullness and decreased appetite. This can result in a reduction in caloric intake and ultimately lead to weight loss.

Another mechanism is through their effect on energy expenditure. GLP-1 receptor agonists increase the body’s energy expenditure, which means that the body burns more calories even when at rest. This effect may be due to an increase in brown adipose tissue (BAT) activity, which is responsible for generating heat and burning calories.

Additionally, GLP-1 receptor agonists have been found to improve insulin sensitivity and glucose control, which may also contribute to weight loss. Insulin resistance is a common feature of obesity, and improving insulin sensitivity can help to reduce body weight.

It is important to note that the weight loss achieved with GLP-1 receptor agonists is typically modest, with an average weight loss of around 4-5% of body weight. However, this can still be clinically significant, as even a small amount of weight loss can lead to improvements in blood sugar control, blood pressure, and cholesterol levels.

GLP-1 receptor agonists are usually administered as an injection once or twice daily. They are generally well-tolerated, but can cause gastrointestinal side effects, such as nausea, vomiting, and diarrhea, especially when starting treatment. These side effects usually improve over time, and patients can be advised to take the medication with food to reduce their severity.

In conclusion, GLP-1 receptor agonists can be an effective option for promoting weight loss in patients with type 2 diabetes mellitus. Their effects on appetite, energy expenditure, and insulin sensitivity can all contribute to weight loss. However, it is important to note that the weight loss achieved with these medications is typically modest and should be considered as part of an overall treatment plan that includes lifestyle modifications, such as diet and exercise.