Short answer: most people building muscle or losing fat need 1.6 to 2.2 grams of protein per kilogram of body weight a day.
How much protein you need, and how much your body can actually put to use, depends on how active you are, what you're working toward and your overall health. If you're trying to change your body composition (build muscle, lose fat, or both), the answer is more than most people expect.
How your body uses protein
There's a limit to how much it can use at once for building muscle.
Your body can only use so much protein in one sitting for muscle protein synthesis, which is the process of building muscle. The figure you'll usually hear is around 20 to 30 grams per meal, because studies found about 20 grams maxed out muscle protein synthesis after a leg workout [1,2]. That doesn't mean a bigger serving is wasted, though. After a full body workout, 40 grams did more than 20 [3], and a 2023 study found 100 grams kept muscle building going for more than 12 hours, longer than 25 grams did [4]. Some of the extra gets burned for energy, but not all of it [5].
If you want to gain lean muscle, or lose fat without losing muscle, you need more protein than the general recommendation for the average adult.
How much to aim for
For building muscle or changing body composition
The usual guideline for building muscle, or losing fat while keeping your muscle, is 1.6 to 2.2 grams of protein per kilogram of body weight [5,6]. That's roughly 0.7 to 1.0 grams per pound.
At 70 kg (154 lbs), that works out to 112 to 154 grams a day.
At 90 kg (198 lbs), it's 144 to 198 grams a day.
For women
The numbers are the same as for men: 1.6 to 2.2 grams per kilogram of body weight. The main sports nutrition guidelines don't set a lower target for women [7].
Where you land in that range depends on how active you are. Harder training and building muscle call for the higher end.
For men
If you're very active or working on your body composition, 1.6 to 2.2 grams per kilogram is the target here too. Your weight, how hard you train and your goals decide where in that range you sit.
Work Out Your Own Number
Enter your weight to see your daily range.
Protein when you're losing fat
When you're trying to lose fat, you want to keep the muscle you have. Eating more protein helps you hold on to it while you're in a calorie deficit. Aim for the higher end of the range, around 2.0 grams per kilogram of body weight or a little more, so the weight you lose comes from fat and not muscle. In one trial, young men on a big calorie deficit who ate 2.4 grams per kilogram gained muscle and lost more fat than men eating 1.2 grams [9]. A review of studies in lean, trained lifters made the case for going even higher while dieting [8].
A few more things to get right
Spread it out. Three to five meals a day, each with a fair share of your protein, keeps muscle protein synthesis going [5,10]. More on this in our guide to the best protein sources and timing for muscle growth.
Pick good sources. Complete proteins like meat, eggs, dairy, quinoa and soy are the best choice, because they contain all the essential amino acids your muscles need to repair and grow. More on this in our guide to the best protein sources and timing for muscle growth.
Don't forget carbs and fat. They do a lot of work for your energy, your hormones and your recovery, so protein shouldn't crowd them out of your plate.
Want a coach to do this with you? See personal training in Vaughan or small group fitness classes.
Need help with food? See nutrition coaching.
References
- Moore DR, Robinson MJ, Fry JL, et al. (2009). "Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men." The American Journal of Clinical Nutrition, 89(1):161-8. PubMed
- Witard OC, Jackman SR, Breen L, et al. (2014). "Myofibrillar muscle protein synthesis rates subsequent to a meal in response to increasing doses of whey protein at rest and after resistance exercise." The American Journal of Clinical Nutrition, 99(1):86-95. PubMed
- Macnaughton LS, Wardle SL, Witard OC, et al. (2016). "The response of muscle protein synthesis following whole-body resistance exercise is greater following 40 g than 20 g of ingested whey protein." Physiological Reports, 4(15). PubMed
- Trommelen J, van Lieshout GAA, Nyakayiru J, et al. (2023). "The anabolic response to protein ingestion during recovery from exercise has no upper limit in magnitude and duration in vivo in humans." Cell Reports. Medicine, 4(12):101324. PubMed
- Schoenfeld BJ, Aragon AA (2018). "How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution." Journal of the International Society of Sports Nutrition, 15:10. PubMed
- Morton RW, Murphy KT, McKellar SR, et al. (2018). "A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults." British Journal of Sports Medicine, 52(6):376-384. PubMed
- Jäger R, Kerksick CM, Campbell BI, et al. (2017). "International Society of Sports Nutrition Position Stand: protein and exercise." Journal of the International Society of Sports Nutrition, 14:20. PubMed
- Helms ER, Zinn C, Rowlands DS, et al. (2014). "A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes." International Journal of Sport Nutrition and Exercise Metabolism, 24(2):127-38. PubMed
- Longland TM, Oikawa SY, Mitchell CJ, et al. (2016). "Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss: a randomized trial." The American Journal of Clinical Nutrition, 103(3):738-46. PubMed
- Areta JL, Burke LM, Ross ML, et al. (2013). "Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis." The Journal of Physiology, 591(9):2319-31. PubMed