The science on this simple question is mixed, our view is based on a review of the science.
If you are an active person or are looking to lose body fat while preserving lean mass or to gain lean mass, a daily intake of 1.2–2g protein per kg bodyweight a day is about right and supported by the current literature.
Below we’ll summarise some of the science and recommendations that helped us arrive at these numbers.
At the low end of the scientific literature 60–75g of protein a day is suggested as sufficient1 while at the higher end one study says2 1.6–1.8 g/kg of bodyweight while another3 suggests even more may be beneficial, some 3.0 g/kg of bodyweight.
Depending on your bodyweight this is a range of around 60–250g per day!
As you can see, this is quite a spread and most studies note that the right amount depends on your activity levels so the answers are more nuanced.
To look into this there are a couple of good reviews of the literature out there, one is the 2007 ACSM position stand for nutrition & performance4 which states 1.2–1.7g/kg per day.
The other is the International Society of Sports Nutrition position stand on protein and exercise which states “Protein intakes of 1.4–2.0 g/kg per day for physically active individuals is not only safe, but may improve the training adaptations to exercise training”5
Our recommendation is therefore based on a review of this research and the the two very thorough position stands above — 1.2–2.0 grams of protein, per kg body weight, per day.
Remember, for most people up to 2g/kg per day is going to be sufficient but it really depends on the nature of the sport or exercise. Resistance, strength and power based exercise which relies on muscle hypertrophy will be at the high end, (2g/kg + perhaps) whereas endurance based exercise may be at the lower end (approx. 1.2–1.4g/kg per day).