GLP-1/GIP Medication & Lifestyle Coaching: Understanding Incretin-based Drugs
More than 5 million Americans are on the GLP-1 and GIP analogs for weight loss and diabetes. These medications have not just transformed medical weight loss offered by doctors but have also impacted various other businesses, including food and beverage manufacturers and wellness and fitness businesses. News media report that Americans are snacking less, eating smaller portions, and downsizing their clothes.
As a Board-Certified Endocrinologist with a busy obesity and diabetes practice, I am acutely aware of the excitement and frustration that many of my patients have recently experienced: they get a prescription filled and take the meds only to experience serious side effects and mixed results. I began prescribing these medications for weight loss in 2014, and after 10 years of coaching my patients, it is clear that people taking these medications need lifestyle change support to find long-term success. It’s also clear that they need a different kind of coaching than traditional weight loss coaching. This blog is the first of two that explores how these medications work and why the lifestyle coaching provided by HLTHYher is essential for supporting these patients.
Incretins are gut hormones that serve as “first responders” for the metabolism of foods we eat. They are secreted as early as 15 minutes after food ingestion and they in turn release insulin, regulate appetite, and modulate the uptake of carbs and fats. Incretins were discovered about one hundred years ago, and research over the last 30 years led to the first incretin-based drug, exenatide, approved by the FDA for diabetes in 2005. Their use for weight loss did not begin until 2014 when liraglutide (Saxenda) was approved for weight loss. In 2021 and 2022, the long-acting semaglutide (Wegovy) and tirzepatide (Zepbound) were approved for weight loss, respectively. Today, semaglutide is approved for diabetes under the name Ozempic and for weight loss under the name Wegovy. Tirzepatide is approved for diabetes under the name Mounjaro and for weight loss under the name Zepbound. Although these once-weekly injectable drugs are similar in action, they have different target organs and side effects.
Semaglutide (Ozempic/Wegovy) lowers blood sugars, cuts appetite, and slows down gastric emptying causing longer-lasting satiety or sensation of fullness. The latter effect is particularly useful for managing the food intake of “big eaters” – people who can eat big portions or second servings. Its main side effects are gastrointestinal in nature: heartburn, nausea, vomiting, diarrhea, and constipation – the latter is the most common and bothersome side effect for most people. Semaglutide also has cardioprotective effects and improves liver function in fatty liver.
Tirzepatide (Mounjaro/Zepbound) also lowers blood sugar, cuts appetite, and slows down GI transit. It appears to impact cravings or desire for foods more than the sensation of stomach fullness. So, it seems to be more effective in people who crave certain foods or who snack in response to stress or strong emotions. It is said that this drug cuts out “food noise.” Tirzepatide is generally better tolerated in the GI tract, but constipation remains a significant problem. Tirzepatide activates the metabolism of skin fat cells, and together with diet, it decreases the thickness of skin fat. This drug also improves liver health in fatty liver.
Overall tirzepatide is more effective for weight loss. At 12 months, the mean weight loss with tirzepatide is about 15.3% compared to 8.3% with semaglutide. Semaglutide appears to have more cardiovascular benefits while tirzepatide is better tolerated and appears to reduce skin fat. People tend to get used to both drugs after a few months and doses need to be increased. More similar medications are in clinical trials and will be available in the next few years, so stay tuned!
