Hello everyone, it’s Dr. Hime.
Today, I want to explain the mechanism behind Mounjaro, which has gained attention as part of the GLP-1 diet. Mounjaro is known for its significantly higher weight loss effects compared to previous GLP-1 receptor agonists. Let’s take a closer look at why that is.
Mounjaro is the brand name, and its generic name is tirzepatide. What sets tirzepatide apart from previous GLP-1 drugs is that it not only acts on the GLP-1 (glucagon-like peptide-1) receptor but also on the GIP (glucose-dependent insulinotropic polypeptide) receptor.
Both GLP-1 and GIP belong to a group of hormones called incretins. Incretins are secreted from the small intestine when food is ingested, and they stimulate the pancreas’ beta cells to release insulin. Insulin is not secreted when blood glucose levels are below 80 mg/dL, which reduces the risk of hypoglycemia compared to drugs like sulfonylureas (SUs) that forcefully stimulate the pancreas.
By promoting the necessary release of insulin, Mounjaro helps to stabilize blood sugar levels and prevent blood sugar spikes, which occur when glucose levels rise rapidly after consuming high-sugar or large meals. These spikes force the pancreas to secrete large amounts of insulin, which can eventually lead to insulin resistance—a condition where the body no longer responds effectively to insulin.
Incretin-related hormones help prevent this by moderating insulin secretion, thereby protecting the pancreas and reducing the risk of weight gain due to insulin overproduction. Specifically, GIP has a powerful appetite-suppressing effect, which, along with blood sugar stabilization, contributes to weight loss.
In addition to helping with weight loss, improving insulin resistance and preventing insulin surges plays a significant role in preventing future diabetes, especially for individuals with a genetic predisposition to type 2 diabetes or those with a history of gestational diabetes, who are at higher risk for developing diabetes later in life.
Given the American Diabetes Association’s (ADA) 2024 guidelines focusing on addressing obesity, incretin-related medications like Mounjaro are expected to become even more prominent in the coming years, both for weight management and as preventive measures against diabetes.