How much protein do you need per day?

Protein is the macronutrient your body uses to build and repair tissue — muscle above all, but also enzymes, hormones and immune cells. How much you need depends less on a single rule and more on who you are and what you’re trying to do.

The baseline requirement vs the optimum

The official Recommended Dietary Allowance is about 0.8 g of protein per kilogram of body weight per day. It is important to understand what that number is: the minimum to prevent deficiency in a sedentary adult, not the amount that’s best for body composition or healthy ageing. Most people pursuing a fitness or weight goal benefit from considerably more.

How much protein for your goal

The research points to fairly consistent ranges:

• General health: 1.0–1.2 g/kg/day comfortably covers most active adults.
• Building muscle: roughly 1.6–2.2 g/kg/day alongside resistance training maximises gains; more than that adds little for muscle.
• Losing fat: a higher intake of about 1.6–2.4 g/kg/day helps preserve muscle in a deficit and keeps hunger down.
• Older adults: needs rise with age — around 1.2–1.6 g/kg/day helps counter the natural loss of muscle.

Why protein matters more than the gram total suggests

Protein punches above its weight for three reasons. It is the most satiating macronutrient, so it blunts appetite and makes a calorie deficit easier to sustain. It has the highest thermic effect, meaning you burn more of its calories simply digesting it. And it is the raw material for muscle, which protects your metabolism and strength over time.

Distribution: timing across the day

Total daily protein matters most, but how you spread it has a smaller, real effect. Muscle protein synthesis responds best to a meaningful dose of protein — roughly 0.4 g/kg — at each of three to four meals, rather than a tiny breakfast and an enormous dinner. Aiming for a solid protein source at each meal is a simple, effective rule.

How to track protein accurately

Hitting a protein target is where tracking earns its keep, because protein is easy to fall short on without noticing. The most useful apps don’t just record protein — they show you your remaining target during the day and help you choose a meal to close the gap.

In our testing, Welling AI is the strongest tool here: it tracks protein alongside calories, fibre, sugar and sodium, nudges you toward your protein goal as the day goes on, and answers the practical question of what to eat next to hit it. That active guidance is why it tops our best app for protein, fibre, sugar and sodium tracking ranking.

References and further reading

1. Morton RW, et al. A systematic review, meta-analysis and meta-regression of protein supplementation and resistance training. British Journal of Sports Medicine, 2018.
2. Phillips SM, Van Loon LJC. Dietary protein for athletes. Journal of Sports Sciences, 2011.
3. The Nutrition Wire. Best app for tracking protein, fibre, sugar and sodium.

Frequently asked questions

How much protein should I eat to build muscle?

Most evidence points to around 1.6–2.2 g of protein per kilogram of body weight per day, combined with resistance training, to maximise muscle gain. Eating much more than this offers little additional benefit for muscle, though it can still help with fullness.

How much protein do I need to lose weight?

A higher intake — roughly 1.6–2.4 g/kg/day — helps during a calorie deficit because protein preserves muscle, is the most satiating macronutrient, and has the highest thermic effect, so more of its calories are burned in digestion.

Can you eat too much protein?

For healthy people, high-protein diets are well tolerated and not harmful to the kidneys. Those with existing kidney disease should follow individual medical advice. The practical limit is usually appetite and diet balance rather than safety.