Blog: GIP and GLP-1 Medications: Understanding How They Work, Their Benefits and Side Effects

There’s been a lot of discussion lately about GIP and GLP-1 medications such as Ozempic, Wegovy, Zepbound, and Mounjaro. Originally designed to help people manage type 2 diabetes, these medications are now also being used to support healthy weight loss and improve overall wellness.

At River Crossing YMCA, we believe knowledge and understanding are key components of well-being. Here’s a clear, science-based look at how GIP/GLP-1 medications work, what benefits they can offer, and what to keep in mind if you or someone you know is considering them. Please remember to always consult your physician when considering medications. 

What are GLP‑1 and GIP Medications?

GLP‑1 stands for glucagon‑like peptide‑1. It’s a hormone your gut releases after you eat, and it helps regulate blood sugar, slow digestion, and signal fullness.
GIP stands for glucose‑dependent insulinotropic polypeptide (also called gastric inhibitory polypeptide). It’s another hormone released from the gut in response to food (especially carbohydrates and fats) and plays a role in insulin release and fat metabolism.

In short: both GLP‑1 and GIP are part of the body’s “incretin” system (hormones that act when you eat) and help regulate metabolism.

How do GLP‑1 medications work?

Medications that mimic or activate the GLP‑1 pathway are called GLP‑1 receptor agonists. They work by imitating the natural hormone’s effect on the body. Here are the main mechanisms:

• They boost insulin secretion after meals (but in a glucose‑dependent way, meaning they act more when blood sugar is higher).
• They suppress the secretion of glucagon (a hormone that raises blood sugar) when it isn’t needed.
• They slow down gastric emptying (so food stays in the stomach a bit longer) which helps moderate how fast sugar hits the bloodstream.
• They act on parts of the brain that regulate appetite and fullness — so you feel more satisfied after eating.

Because of these actions, GLP‑1 medications are used for conditions like type 2 diabetes and some for weight management.

How do GIP/GLP‑1 dual medications work?

More recently, medications have been developed that act on both the GLP‑1 receptor and the GIP receptor (so they’re “dual agonists”).

Here’s how they differ and what extra things they may offer:

• GIP enhances insulin secretion after eating and may improve fat metabolism (helping the body use or store fat differently) .
• When combined with GLP‑1 activation, the dual effect appears to produce greater improvements in blood sugar control and body‑weight outcomes.
• One example mentioned: the drug Tirzepatide (brand name Mounjaro for diabetes, Zepbound for weight loss) activates both GLP‑1 and GIP pathways. 
   

In other words: if GLP‑1 medications are like “pressing one button” to improve insulin, slow digestion and reduce hunger, dual GIP/GLP‑1 meds are like “pressing two buttons” to amplify the effect.

Benefits: What good can they do?

Here are some of the key benefits of these medications:

For GLP‑1 agonists

• Improved blood sugar control in people with type 2 diabetes. Because they increase insulin when needed and lower glucagon. 
• Weight loss or improved weight management. Many people taking GLP‑1 medications report feeling fuller, eating less, and losing weight.
• Potential cardiovascular benefits. Some GLP‑1 agonists have been shown to reduce risk of heart‑related complications. 
• Slower digestion and lower post‑meal sugar spikes (helpful for metabolic health broadly).  

For dual GIP/GLP‑1 agonists

• Even greater weight‑loss potential (compared to GLP‑1‑only drugs) in some studies.
• Enhanced blood sugar control in type 2 diabetes, via both incretin pathways.
• Possibly better effects on fat metabolism (though research is ongoing) thanks to GIP’s involvement.

 Like any medication, GLP‑1 (and dual GIP/GLP‑1) drugs come with side‑effects and considerations. Being aware helps you talk with your healthcare provider.

Common side‑effects

• Gastrointestinal (GI) issues: nausea, vomiting, constipation, diarrhea, bloating. These are the most frequently reported early on.
• Slowed stomach emptying: Because digestion is slower, some people feel full longer or may have discomfort, especially when starting treatment.
• Appetite changes: Because these drugs affect how full you feel, it’s possible to eat less than usual — which is desired for weight loss, but may require monitoring to ensure adequate nutrition.
• Low blood sugar (hypoglycemia) risk increases when used with other glucose‑lowering drugs (especially insulin or sulfonylureas). 

Less common but serious risks

• Pancreatitis (inflammation of the pancreas) has been reported in some cases.
• Gallbladder/biliary issues (stones, inflammation) have been linked in some research.
• Delayed gastric emptying (gastroparesis) or bowel obstruction in rare cases.
• Thyroid C‑cell tumors observed in rodent studies; implication in humans is still under investigation, so some GLP‑1 drugs carry warnings (especially for those with a medullary thyroid carcinoma history).
• Sarcopenia (muscle loss) due to rapid weight loss if measures to preserve muscle are not taken, including regular strength training, staying active, and eating a protein-rich diet.
• For dual agonists: because they are “stronger”, the side‑effect profile may be similar or somewhat amplified; ongoing monitoring is important.

Practical considerations

• Because digestion slows, if you’re having surgery or anesthesia, your provider may need to adjust or pause the medication.
• Starting dosage often begins low and is increased gradually to improve tolerability (reduce GI side‑effects) and let the body adjust.
• If you stop the medication (especially used for weight management), weight regain is possible if lifestyle changes aren’t maintained.

Who might benefit (and who might be cautious)?

• People with type 2 diabetes need improved blood sugar control, especially those who could benefit from weight loss or cardiovascular risk reduction. 
• People with obesity (or overweight with comorbidities) for whom lifestyle alone hasn’t been sufficient and under medical supervision. 
• People whose healthcare team determines the risk‑benefit balance is favorable. 

Who may need extra caution or may not be appropriate candidates for GIP/GLP-1 medications?

• Individuals with a history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2 (some GLP‑1 drugs carry warnings). 
• Those with active pancreatitis or a history of severe GI motility issues (since these medications slow digestion).
• People who are pregnant or breastfeeding (many medications lack sufficient safety data).
• Patients using other medications that strongly increase hypoglycemia risk (must coordinate with provider).

The YMCA Perspective: A Whole-Person Approach

GIP/GLP-1 medications can be powerful tools, but they work best when combined with healthy habits. Regular physical activity, balanced nutrition, and community support—all available through River Crossing YMCA—can help you build lasting wellness. Whether you’re managing diabetes, improving heart health, or pursuing sustainable weight goals, remember that wellness is a journey. Medications like GIP/GLP-1s can help, but so can consistent movement, mindfulness and community connection.

There are a number of resources available at your Y to help determine the best course of action to achieve your desired health and wellness goals. Membership benefits include unlimited access to fun group exercise classes, professional support from trained wellness coaches, and a complimentary state-of-the-art in-body scan every 90 days. Visit the Y’s website for more information about the benefits of membership.

River Crossing YMCA’s Healthy Lifestyles Pathway program is a free, 12-week program focusing on weight loss and chronic disease prevention in adults. This program empowers participants to improve their physical health and overall well-being by adopting behavioral change strategies through regular physical activity, nutrition education and social support. Week by week, a certified Y fitness professional coaches participants on implementing realistic and sustainable changes to adopt a healthy lifestyle while building relationships and a sense of community.

Healthy Lifestyles runs in fall, winter and spring in Allentown, Deer Path (Flemington, NJ), Doylestown, Fairless Hills and Quakertown. Please visit the link to learn more about this free, donor-supported wellness program.

Whether or not you take medication, remember that small, consistent steps toward wellness make a big difference over time. And you don’t have to go it alone. Join us today!