If you’re on a GLP-1 medication like semaglutide (Ozempic, Wegovy) or tirzepatide (Mounjaro, Zepbound), you’ve probably heard people emphasize protein intake—and for good reason.
While these medications are highly effective for weight loss and blood sugar control, they also change how your body processes food, making protein more important than ever.
Without enough protein, you risk muscle loss, slower metabolism, and fatigue. If you’re taking a GLP-1, understanding why protein matters and how to incorporate it into your diet can help you get better results while maintaining muscle, energy, and long-term health.
What is Protein and Why Do We Need It?
Protein is one of the three macronutrients (alongside carbohydrates and fats) that our bodies need to function. It’s made up of amino acids, which are the building blocks of muscle, tissues, enzymes, and hormones.
Unlike carbs and fats, which your body can store for later use, protein needs to be consumed regularly because it’s constantly being broken down and rebuilt.
Key Roles of Protein in the Body:
Builds and repairs muscle and tissues
Supports immune function
Regulates enzymes and hormones
Helps keep you full and satisfied
Supports skin, hair, and nail health
When you’re losing weight on a GLP-1, protein becomes even more critical because it helps prevent muscle loss—a common issue when cutting calories.
While there’s no official protein requirement specifically for GLP-1 users, most experts recommend 0.6–1.0 grams of protein per pound of body weight to maintain muscle and prevent side effects like fatigue and hair thinning.
For someone losing weight on a GLP-1, aiming for 80–120 grams of protein per day is a good baseline, depending on body size, activity level, and muscle preservation goals. Prioritizing lean meats, eggs, Greek yogurt, and protein supplements can help meet this target, even with a reduced appetite.
How Do GLP-1 Medications Work?
GLP-1 receptor agonists mimic the body’s natural glucagon-like peptide-1 hormone, which regulates blood sugar and appetite. These medications help with weight loss and diabetes management by:
Slowing digestion – Food stays in the stomach longer, reducing hunger.
Suppressing appetite – You feel full with smaller portions.
Regulating blood sugar – Helps control insulin and glucose levels.
Reducing cravings – Less desire for high-calorie, processed foods.
Because GLP-1s significantly reduce appetite, people naturally eat less—which can lead to nutrient deficiencies if they’re not careful. Protein intake becomes crucial to ensure the body still gets what it needs, even when food intake is reduced.
Why Is Protein Such a Big Part of GLP-1 Diets?
When losing weight, your body doesn’t just burn fat—it can break down muscle tissue too. Losing muscle mass is a problem because muscle supports metabolism, meaning less muscle = fewer calories burned at rest.
Since GLP-1s cause a natural calorie reduction, there’s an increased risk of muscle loss if protein intake is too low.
Protein Helps GLP-1 Users By:
✅ Preserving Muscle – Prevents excessive muscle breakdown while losing weight.
✅ Boosting Metabolism – Muscle burns more calories, helping with long-term weight management.
✅ Enhancing Fullness – Protein is more satiating than carbs or fat, helping reduce cravings.
✅ Supporting Energy – Helps prevent fatigue, which can be common on GLP-1s.
✅ Maintaining Skin, Hair, and Nails – Many GLP-1 users report hair thinning due to low protein intake.
Even though GLP-1 medications make it easier to eat less, the goal isn’t just weight loss—it’s fat loss while keeping muscle and energy levels high.
What Happens If You Don’t Get Enough Protein?
Not getting enough protein while on GLP-1s can lead to several unwanted effects, including:
1. Muscle Loss
If the body doesn’t get enough protein, it breaks down muscle tissue for energy instead of fat. This can lead to weaker muscles, slower metabolism, and less strength over time.
2. Slower Metabolism
Muscle burns more calories than fat, so losing muscle slows your metabolic rate, making it easier to regain weight once you stop the medication.
3. Fatigue and Weakness
Low protein intake can lead to energy crashes, sluggishness, and difficulty staying active, which is especially concerning for those trying to maintain an exercise routine.
4. Hair Thinning and Brittle Nails
Hair and nails rely on keratin, a protein-based structure. Without enough protein, hair can become brittle and thin, and nails may become weak or prone to breaking.
5. Increased Hunger and Cravings
Protein helps regulate appetite hormones, so low intake can lead to more cravings and less satisfaction after meals.
Best Sources of Protein in Food
For those on GLP-1 medications, focusing on high-quality protein sources is key. Since these meds reduce appetite, it’s important to choose nutrient-dense options.
Animal-Based Proteins
Chicken, turkey, lean beef – High in protein with minimal fat.
Eggs and egg whites – Affordable and packed with nutrients.
Fish and seafood – Salmon, tuna, and shrimp offer protein plus omega-3s.
Greek yogurt and cottage cheese – High-protein dairy with gut health benefits.
Plant-Based Proteins
Tofu and tempeh – Great vegetarian options with all essential amino acids.
Lentils and beans – Fiber-rich and protein-packed.
Quinoa – A complete plant-based protein.
Nuts and seeds – Almonds, chia, and hemp seeds offer protein and healthy fats.
Eating a mix of animal and plant-based proteins ensures a diverse nutrient intake while keeping meals interesting. However, if you have specific dietary needs, there are plenty of protein options in the plant and animal kingdoms separately.
Best Protein Supplements for GLP-1 Users
Since GLP-1s reduce appetite, eating enough protein through food alone can be tough. Supplements can fill the gap, ensuring you get enough protein without needing large meals.
Best Protein Supplements:
Whey protein – Fast-digesting and ideal for post-workout recovery.
Casein protein – Slow-digesting, great for sustained muscle repair.
Collagen protein – Supports skin, hair, joints, and gut health.
Plant-based protein – Pea, hemp, and rice protein for vegan-friendly options.
Protein bars – A convenient, grab-and-go option with balanced macros.
For those struggling with nausea on GLP-1s, protein shakes or powders mixed with almond milk can be an easy, gentle way to increase intake.
READ MORE: Top 8 Protein Bars from Nutrition Expert
Meal Planning for GLP-1 Diets Made Easy
Ashley at Legg Day Fitness offers nutritional counseling, accountability, and on-demand fitness to help you maximize your GLP-1 journey. She keeps you on track, managing side effects and cravings while ensuring you get enough protein and nutrients. With her guidance, you’ll stay consistent, feel strong, and never go hungry!
