How much protein do I actually need per day?

The recommendations diverge for a simple reason: the right amount depends on what you want and how you live. A meta-analysis by Morton and colleagues (2018) pooled 49 studies with 1,863 participants and found that protein beyond a total intake of 1.62 grams per kilogram of body weight per day produced no further muscle gain from resistance training (95% confidence interval 1.03–2.20). Around that level the curve flattens out.

The International Society of Sports Nutrition (ISSN) lands in the same range and puts 1.4–2.0 g/kg per day as sufficient for most people who exercise. That it is a range rather than a single number reflects how the need shifts with training volume, age, and whether you are eating in a deficit at the same time.

For someone who does not train, the need is lower. The evidence behind the Nordic Nutrition Recommendations notes that protein intake in the Nordic countries sits at 15–19 percent of energy in practice, which for most people covers and exceeds the basic requirement. Two situations justify the higher end of the range: weight loss, when ample protein helps preserve muscle while you shed fat, and older age, when the body responds less well to protein and muscle mass otherwise declines.

The range is wide, and where a range exists different players can pick the end that suits them. Makers of protein powder and bars profit directly from the number being seen as high and hard to reach with regular food, so the message that you never get enough sells products. Fitness culture reinforces it: more always feels better, and a high protein target becomes an identity marker rather than a physiological need. In the other direction, the official baseline has sometimes been treated as a ceiling instead of a floor, leaving active people convinced they are overdoing it when they eat above the minimum. The truth sits in the middle, but the middle sells neither supplements nor headlines.

Aim for roughly 1.6 grams per kilogram of body weight per day if you train and want to build or keep muscle. At 70 kilos that is around 110 grams, spread across the day's meals. If you train and are losing weight at the same time, you can go toward the higher end, near 2.0 g/kg. For older people or those with illness, the level should be set individually with a healthcare professional. Regular food goes a long way: meat, fish, eggs, dairy, and legumes. Powder is a convenient extra, never a requirement. Work out your own number with the protein calculator.