GLP-1 Weight Loss Calculator

Most people on semaglutide (Ozempic/Wegovy) naturally eat 20-35% fewer calories due to reduced appetite. For safe weight loss, women should not go below 1,200 calories per day and men should not go below 1,500 calories per day. This calculator factors in your medication, body stats, and activity level to give you a personalized calorie target. Work with your healthcare provider to find the right balance between weight loss pace and adequate nutrition.

Research shows that 25-40% of weight lost on GLP-1 medications can be lean muscle mass rather than fat. Eating adequate protein (1.2-2.0g per kg body weight, depending on your goal) helps preserve muscle during weight loss. Muscle preservation is critical for maintaining your metabolic rate, functional strength, and long-term weight maintenance. Aim for 30-40g of protein at each meal and prioritize protein-rich foods first when your appetite is reduced.

Semaglutide (Ozempic, Wegovy) is a GLP-1 receptor agonist that reduces appetite by ~25%. Tirzepatide (Mounjaro, Zepbound) is a dual GIP/GLP-1 receptor agonist that reduces appetite by ~30% and typically produces greater weight loss in clinical trials. Both medications are weekly injections. Tirzepatide showed average weight loss of 15-22.5% of body weight in the SURMOUNT-1 trial, compared to about 15% with semaglutide in the STEP 1 trial. Your doctor will recommend the best option based on your health profile.

You should drink at least 2 liters (about 8 cups) of water daily, and ideally 0.033 liters per kilogram of body weight. GLP-1 medications can cause nausea, vomiting, and diarrhea, all of which increase dehydration risk. Adequate hydration also supports kidney function, helps manage constipation (a common side effect), and can reduce nausea severity. Sip water throughout the day rather than drinking large amounts at once, which can worsen nausea.

Yes, resistance training 2-3 times per week is strongly recommended while on GLP-1 therapy. Because these medications can cause muscle loss alongside fat loss, strength training is one of the most effective strategies to preserve lean mass. Combine resistance exercise with adequate protein intake for the best results. Start with moderate intensity and increase gradually, especially during the dose titration phase when side effects may be more prominent. Walking and light cardio are also beneficial for overall health.

No. This calculator provides general nutrition guidance based on published research and clinical trial data. It does not replace advice from your prescribing physician, endocrinologist, or registered dietitian. Every individual responds differently to GLP-1 medications, and your specific health conditions, other medications, and medical history all affect the right nutrition plan for you. Use these results as a starting point for conversations with your healthcare team.