Protein for Weight Loss: How Much You Need and Why It Works
To lose fat and keep muscle, aim for 0.54g/lb (1.2g/kg) of body weight a day, or 0.73g/lb (1.6g/kg) if you strength train. Daily grams by body weight, the research on why protein helps, and the best foods per calorie.
The short answer: eat about 0.54g/lb (1.2g/kg) of body weight per day while losing weight. If you strength train twice a week or more, aim for 0.73g/lb (1.6g/kg). For a 180lb person, that is 98g a day, or 131g with strength training.
Protein will not cause weight loss on its own; you still need to eat fewer calories than you burn. What it does is make that deficit easier to stick to and make sure more of the weight you lose is fat rather than muscle.
Daily Protein for Weight Loss by Body Weight
| Body weight | Losing weight (1.2g/kg) | Losing weight and strength training (1.6g/kg) |
|---|---|---|
| 120lb (54kg) | 65g | 87g |
| 140lb (64kg) | 76g | 102g |
| 160lb (73kg) | 87g | 116g |
| 180lb (82kg) | 98g | 131g |
| 200lb (91kg) | 109g | 145g |
| 220lb (100kg) | 120g | 160g |
| 240lb (109kg) | 131g | 174g |
| 260lb (118kg) | 142g | 189g |
| 280lb (127kg) | 152g | 203g |
| 300lb (136kg) | 163g | 218g |
Get an exact number for your weight, age and training with the protein calculator for weight loss. These targets use current body weight; if you have a lot of weight to lose, your doctor or dietitian may suggest an adjusted weight.
Why Protein Helps You Lose Weight
1. It Keeps You Fuller
Protein is the most filling macronutrient, calorie for calorie. A review in Advances in Nutrition concluded that higher protein meals increase fullness and can reduce how much you eat later Cuenca-Sánchez et al., Advances in Nutrition, 2015. Feeling less hungry is most of the battle in a calorie deficit.
2. It Costs More Energy to Digest
Your body burns energy digesting food, and protein costs the most: roughly 20 to 30% of its calories, compared with 5 to 10% for carbohydrate and 0 to 3% for fat. In a controlled study, a diet with 25% of calories from protein raised daily energy expenditure compared with a diet with 10% protein Hochstenbach-Waelen et al., American Journal of Clinical Nutrition, 2009. The effect is real but modest, so treat it as a bonus.
3. It Protects Muscle
When you eat less than you burn, your body breaks down some muscle along with fat. Keeping muscle matters because it supports your metabolism, strength and long term weight maintenance.
A meta-analysis of 24 trials found that higher protein, calorie restricted diets led to more fat loss and less loss of lean mass than standard protein diets Wycherley et al., American Journal of Clinical Nutrition, 2012. A review in the American Journal of Clinical Nutrition supports 1.2 to 1.6g/kg per day during weight loss Leidy et al., American Journal of Clinical Nutrition, 2015.
When to Aim Higher
Strength training changes the picture. In a 4 week study of young men on a large calorie deficit with intense training six days a week, the group eating 2.4g/kg gained about 1.2kg of lean mass and lost more fat, while the 1.2g/kg group roughly held their lean mass Longland et al., American Journal of Clinical Nutrition, 2016. Both groups lost fat.
For very lean, trained athletes dieting hard, one review suggests 2.3 to 3.1g/kg of lean body mass Helms et al., International Journal of Sport Nutrition and Exercise Metabolism, 2014. Most people trying to lose weight do not need that. 0.73g/lb (1.6g/kg) covers almost everyone who lifts, and it is where muscle gains level off in the largest meta-analysis on the subject Morton et al., British Journal of Sports Medicine, 2018.
On a GLP-1 or Over 65
On Ozempic, Wegovy, Mounjaro or Zepbound, appetite drops so far that protein is easy to miss. Clinical guidance recommends at least 0.54g/lb (1.2g/kg) during treatment Sievenpiper et al., Obesity Pillars, 2025. The GLP-1 protein calculator applies that minimum.
Over 65, muscle is harder to rebuild once lost. Expert groups recommend at least 1.0 to 1.2g/kg per day for healthy older adults Bauer et al., PROT-AGE Study Group, JAMDA, 2013, and the weight loss target of 0.54g/lb (1.2g/kg) already meets that. If a shake makes that easier, our best protein powder for seniors ranking compares verified labels.
Best Protein Foods for Weight Loss
When calories are limited, protein per calorie matters more than protein per gram. These foods give you the most protein for the fewest calories (USDA values):
| Food | Protein per 100g | Calories per 100g | Protein per 100 calories |
|---|---|---|---|
| Egg whites | 10.9g | 52 | 21.0g |
| Chicken breast, roasted | 31.0g | 165 | 18.8g |
| Greek yogurt, plain nonfat | 10.2g | 59 | 17.3g |
| Cottage cheese, 1% milkfat | 12.4g | 72 | 17.2g |
| Whole eggs | 12.6g | 143 | 8.8g |
For packaged options, our rankings score every product on protein per 100 calories: see the best protein shakes, best protein bars and best high protein yogurt.
What a Weight Loss Day Looks Like
Here is 87g of protein, the target for a 160lb person losing weight:
| Meal | Food | Protein |
|---|---|---|
| Breakfast | 1 cup nonfat plain Greek yogurt | 25g |
| Lunch | 2 large eggs and 1oz cheddar | 19g |
| Dinner | 4oz cooked chicken breast | 35g |
| Snack | 1 cup 1% milk | 8g |
| Total | 87g |
More ideas: high protein breakfast ideas with real gram counts, and high protein snacks for weight loss.
How to Eat More Protein Without Trying Harder
- Build each meal around the protein first, then add the rest.
- Aim for 25 to 40g per meal rather than one big serving at dinner.
- Swap snacks: Greek yogurt or cottage cheese instead of crackers or granola bars.
- Use a shake when a meal falls short. Many ready to drink shakes give 30g for about 150 calories.
- Track it. Most people guess their protein intake wrong, and it is usually too high. Any of the best protein tracker apps will show your real number within a week.
Track Your Protein, Not Everything
You do not have to log every calorie to benefit from more protein. Protein Pal sets your weight loss protein goal using the rules above and shows how close you are after each meal. It is free to download, and manual logging is free. Photo scanning is part of Pro. Available on iPhone and Android.
Related Reading
Frequently Asked Questions
- How much protein should I eat to lose weight?
- About 0.54g/lb (1.2g/kg) of body weight per day, or 0.73g/lb (1.6g/kg) if you strength train twice a week or more. For a 180lb person that is 98g a day, or 131g with strength training.
- Does eating more protein help you lose weight?
- It helps, but it does not replace a calorie deficit. Protein keeps you fuller, takes more energy to digest, and protects muscle, so more of the weight you lose is fat.
- Should I use my current weight or goal weight?
- Most guidance uses current body weight. If you have a lot of weight to lose, that can give a very high number, so a doctor or dietitian may suggest an adjusted or goal weight.
- Is 100g of protein a day enough to lose weight?
- For most people up to about 183lb, yes: 100g meets the 0.54g/lb (1.2g/kg) weight loss target. If you strength train, 100g covers people up to about 137lb.
- Can I lose muscle while losing weight?
- Yes, especially with fast weight loss, low protein and no strength training. Eating enough protein and lifting weights two or more times a week are the two best ways to keep it.
- What are the best protein foods for weight loss?
- Foods with the most protein per calorie: egg whites (21g per 100 calories), chicken breast (18.8g), plain nonfat Greek yogurt (17.3g) and 1% cottage cheese (17.2g), based on USDA data.