Not losing weight on tirzepatide? Here’s what to do about it

Key Points

• Clinical trials showed tirzepatide can lead to 16-22.5% body weight loss, with results varying by dosage
• Combining medication with lifestyle changes helped participants lose an extra 21.1% weight in 12 weeks, reaching 26.6% in slightly over a year
• Lifestyle factors, hormonal imbalances, dosage, and how regular you are with taking tirzepatide can play a role in your weight loss
• Working with your healthcare provider and a registered dietitian can help you maximize your weight loss on tirzepatide

When tirzepatide, the weight loss and diabetes drug, launched under the brand names Zepbound and Mounjaro, the marketing message made weight loss seem easy: take the drug, feel less hungry, and watch the pounds drop.

But, real-world experience tells a more complex story. Not everyone sees the dramatic results they expected from this new drug. Let's look at some reasons why you’re not losing weight on tirzepatide and what to do about it.

How does tirzepatide work?

Tirzepatide is the active ingredient in two medications from drug manufacturer Eli Lilly and Company: Zepbound for weight loss and Mounjaro for type 2 diabetes management.

Tirzepatide works by copying the action of two natural hormones in your body that control metabolism. These hormones affect your appetite, slow down digestion, and influence how your body processes blood sugar.

The two hormones—GLP-1 and GIP—play different but complementary roles. GLP-1 signals your brain when you've eaten enough and slows down food movement through your digestive system while also helping manage blood sugar levels. GIP works alongside GLP-1 to manage blood sugar and how your body stores energy.

Most new-wave diabetes drugs have one of these hormones, but tirzepatide engages both—making it distinct in how it approaches blood sugar and weight management.

How much weight can you lose on tirzepatide?

Phase 3 clinical trials of tirzepatide showed the following weight loss results—an average of 16% of their body weight on the 5mg dose, 21.4% on 10mg, and 22.5% on 15mg. Participants in the trial had obesity or were overweight with weight-related health conditions.

While these results are promising, your individual response to tirzepatide may differ. Let's explore some common reasons why you might not be seeing the weight changes you expected.

What to do when you’re not losing weight on tirzepatide

Review food choices

Tirzepatide can help with weight loss, but what you eat still makes a huge difference.

The science backs this up. When Eli Lilly studied weight loss results on tirzepatide, they found something interesting: people who combined the medication with better eating habits and exercise lost an extra 21.1% of their weight in just 12 weeks. By week 84, they experienced a 26.6% weight loss—showing just how much your lifestyle choices matter.

Simple food swaps

Don't worry—you don't need to transform your entire diet overnight. Start with small changes that fit your life, like swapping fried chicken for grilled, choosing water instead of soda with meals, or adding an extra serving of vegetables to your plate. Even something as simple as having a small salad before your favorite pizza can make a difference.

Other challenges to a healthy diet

While the tips above may be helpful, weight loss is personal. Maybe you crave salty chips, not sweet treats. Perhaps your jam-packed schedule makes regular meals challenging.

Or maybe you're just tired of making decisions after taking care of everyone else all day. Did you know we make an average of 35,000 decisions a day? This mental load may lead to decision fatigue—and reaching for those comfort foods after work or by dinnertime.

That's where a weight loss dietitian can be a game-changer. They'll create a custom eating plan that fits your life, take the guesswork out of food choices, and help you enhance the effect of weight loss on tirzepatide.

Shake off a weight loss plateau

Not losing weight on tirzepatide, and wondering why? Sometimes, it’s not because something’s wrong. It just might be your body's natural response to weight loss.

Think of it this way: a smaller body needs less energy to function. As you lose weight, your body adjusts to its new size. This may mean the eating habits that worked so well until now may need some tweaking to get to the next level.

Ready to break through a weight loss plateau? Here's what may help:

Pack each meal with the right amount of protein

The Academy of Nutrition and Dietetics (AND) suggests getting 10% to 35% of your calories from protein, your exact needs depend on several factors—your activity level, age, whether you lift weights, and other aspects of your lifestyle.

Also, consider spreading your protein intake across the entire day.

Take a good look at your portion sizes

Try balancing your plate with half your plate filled with whole vegetables, a quarter with lean protein, and the rest with quinoa, brown rice, or another whole grain.

Analyze your alcohol intake

Alcohol can slow your weight loss in sneaky ways—it's not just about the calories. When you drink, your body hits pause on fat burning to process the alcohol first. Plus, those drinks often lead to late-night snacking.

Try limiting drinks to special occasions, alternating with water, or skipping the alcohol altogether—your progress might speed up.

Journal your daily intake for clues

Taking notes about your eating patterns for a few weeks can reveal surprising clues about your weight loss challenges. Jot down not just what you eat but also how hungry you feel before meals and snacks, plus your water intake throughout the day.

The goal isn't to criticize your choices—it's to spot patterns. Maybe you're always starving before dinner when a handful of nuts and some water an hour earlier could help. Or perhaps you need a more filling breakfast to avoid overwhelming hunger by lunch.

Get the right support

Remember, weight loss rarely follows a straight line—these starts and stops are part of the journey. With everything else you're juggling, you shouldn't have to figure it out alone. A weight loss registered dietitian who understands weight loss plateaus can help fine-tune your approach while keeping your nutrition on track.

Get moving

Physical activity remains important, even on diabetes weight-loss drugs like tirzepatide. Exercise does more than burn calories—it makes your body more sensitive to insulin and revs up your metabolism, helping you burn calories even while you rest.

In contrast, losing weight solely through dieting often leads to a loss of both fat and muscle, which can slow your metabolism and make it tougher to maintain progress.

Looking for a specific exercise goal? The US CDC suggests about 150 minutes of moderate activity each week. Breaking this down makes it more manageable: think of it as 30-minute activities five times a week. They also recommend muscle-strengthening activities twice a week to help you preserve muscle mass and boost your metabolism.

If you’re working out but not losing weight, consider switching up your routine and trying a new type of exercise.

Consider underlying medical conditions

Sometimes, it’s not just about diet and exercise. Conditions like hypothyroidism, PCOS, insulin resistance, or even stress and lack of sleep can slow down weight loss. Certain medications (like antidepressants or steroids) can also affect weight. The hormonal shifts during menopause can also make weight loss more challenging.

If you suspect an underlying issue, talk to your healthcare provider. Addressing these factors can make a huge difference in your weight loss journey.

You may need a different dosage

Starting tirzepatide is a gradual process—most people begin with 2.5mg to help their bodies adjust. This starter dose lets you and your doctor see how your body responds, but it's not where you'll see significant weight loss.

Not seeing much change? Remember that getting to the right dose takes time—moving up too quickly can increase side effects. Talk with your healthcare provider about your progress. They'll help determine if and when a dose adjustment makes sense for you.

Is it an inconsistent dosing schedule?

Missing doses or stopping and then restarting tirzepatide after a long break can reduce its effectiveness.

Stay on track by setting phone reminders, using a medication tracker app, or linking your dose to a daily routine like breakfast. Consistent medication use is key to achieving the best long-term results.

Final Thoughts

Tirzepatide can make a difference in your weight loss journey, but the best results come when you combine it with healthy lifestyle changes.

Success comes from making better food choices, finding ways to stay active that you enjoy, and taking your medication as prescribed. Some days will be easier than others, and that's completely normal. The key is to keep going, even when progress feels slow.

Consider partnering with experts along the way. A registered weight loss dietitian can bring valuable expertise to your weight loss journey. They can suggest meal ideas that fit your schedule to help you navigate special occasions and stop food cravings.

Frequently Asked Questions (FAQs)

How can I get tirzepatide for weight loss?

Tirzepatide is a prescription medication, so you can only obtain it with a doctor's prescription. Your healthcare provider can help determine if tirzepatide is right for you. Insurance coverage can also determine what medication option is available to you.

Tirzepatide comes as two different medications: Zepbound, which is specifically FDA-approved for weight loss, and Mounjaro, which is authorized by the US FDA for people with type 2 diabetes. Sometimes, Mounjaro may be prescribed “off-label” for weight loss.

Can dietitians prescribe tirzepatide?

Dietitians cannot prescribe medication. Only physicians—specifically MDs and DOs—have the authority to prescribe this medication, whether you know it as Zepbound or Mounjaro. These doctors will need to evaluate your health and evaluate if you meet the eligibility criteria.

How to maximize weight loss on tirzepatide?

To get better weight loss results with tirzepatide, start by focusing on balanced, nutritious meals and finding ways to stay active that fit your lifestyle. Remember to take your medication as prescribed—consistency matters.

A registered weight loss dietitian who specializes in weight loss can help create a custom eating plan that works for you while your doctor can ensure you're on track with the right dosage.

Tirzepatide vs. semaglutide: What’s the difference?

While both medications help with weight loss, they work differently in your body. Semaglutide (available as Ozempic and Wegovy) works with just one hormone—GLP-1 that helps reduce appetite.

Tirzepatide (available as Zepbound and Mounjaro) works with two different hormones in your body—GLP-1 and GIP.

Each of these medications has different FDA approvals. Zepbound is approved for weight loss. Mounjaro is approved to help manage blood sugar in adults with type 2 diabetes. As for Semaglutide, it's available as Wegovy for weight loss and as Ozempic for type 2 diabetes.

Your healthcare provider can help determine which medication might be right for you.

Which is better for weight loss, Wegovy or Zepbound?

Both Zepbound and Wegovy can help with weight loss, but they work slightly differently in your body. Zepbound works with two naturally occurring hormones (GLP-1 and GIP) that help manage appetite and blood sugar, while Wegovy works with just one of these hormones (GLP-1).

In a clinical trial comparing Zepbound (tirzepatide) with Wegovy (semaglutide), people taking Zepbound achieved an average weight loss of 20.2% of their starting weight, compared to 13.7% for those taking Wegovy. This news was announced by Eli Lilly, the manufacturer of Zepbound.

However, numbers alone shouldn't determine which medication is right for you. Your healthcare provider can recommend the best option based on your individual health needs, treatment goals, and potential side effects.

Start losing weight on tirzepatide. Find a weight loss dietitian who accepts your insurance.

The views expressed by authors and contributors of such content are not endorsed or approved by Fay and are intended for informational purposes only. The content is reviewed by Fay only to confirm educational value and audience interest. You are encouraged to discuss any questions that you may have about your health with a healthcare provider.