How much protein do I need?

How the calculator works

It counts in grams of protein per kilogram of bodyweight per day. Your goal sets the range, your training days pick the target inside it.

• Maintain: 1.4 to 1.8 g per kg. The ISSN considers 1.4 to 2.0 g enough for most people who train.
• Build muscle: 1.6 to 2.2 g per kg. In the meta-analysis by Morton and colleagues, muscle mass kept growing up to about 1.6 g and barely beyond. The upper end of the confidence interval was 2.2 g.
• Lose fat: 1.8 to 2.4 g per kg. In a calorie deficit the body needs more protein to hold on to its muscle. For lean lifters, reviews even give 2.3 to 3.1 g per kg of lean mass.

With 1 to 2 training days the calculator takes the low end, with 3 to 4 the middle, from 5 days the high end. Without training it shows 0.8 g per kg, about the reference intake for healthy adults.

Why a range and not one exact number

Studies measure groups, not you. Anywhere in the range is right. Whether you eat 150 or 165 g on a given day changes little. What counts is the average over the week.

Spread over the day

About 0.4 g per kg in each of four meals gets you to 1.6 g per kg. At 80 kg that is a little over 30 g per meal. More per meal does no harm. You just do not need to eat it all at once.

When to count differently

• A lot of extra weight: count with your goal weight instead of your current weight. Otherwise the number comes out higher than your body needs.
• Kidney disease: other rules apply. Talk to your doctor first. For healthy people the ISSN found no signs of harm at these amounts.
• Under 18 or over 65: reference values differ for these ages.

Protein alone builds no muscle

The signal comes from training. Protein makes sure the body can do something with it. Eat more protein without training and you build hardly any muscle. How to bring both together in a deficit is in Lose fat without losing muscle.