Health & Wellbeing
Daily Protein Needs
Estimated protein target based on weight and activity.
Education and reference only. Not a substitute for clinical judgement, local policy or product labelling. Always verify before clinical use. Values are calculated in your browser and never stored.
Background
Protein requirements are conventionally expressed per kilogram of body weight. The UK reference nutrient intake for adults is 0.75 g per kg per day — the amount judged sufficient for around 97% of the healthy adult population. This calculator lets you scale that upward for training load and older age, using 0.8 g/kg for general health, 1.2 g/kg for active people and older adults, 1.6 g/kg for regular strength training and 2.0 g/kg for those building muscle.
Interpreting the result
The lower end of the range is a requirement; the upper end is a performance target. The UK reference intake of 0.75 g/kg is the amount needed to avoid deficiency, and most adults in the UK already exceed it comfortably from ordinary food. The higher figures come from sports nutrition practice, where additional protein supports training adaptation and helps preserve lean mass during weight loss. They are not a health requirement, and going above roughly 2 g/kg has not been shown to add further benefit in healthy people.
Advice
Spread protein across the day. Good sources include meat, fish, eggs, dairy, beans, pulses, tofu, nuts and seeds. Most people meet their needs from food without supplements.
Worked example
An 80 kg adult who strength trains regularly, at 1.6 g/kg: 80 x 1.6 = 128 g of protein a day. Spread across four meals that is about 32 g each — roughly a chicken breast, or a large tin of beans with a portion of Greek yoghurt.
Pearls / pitfalls
- Distribution matters as well as total: spreading protein across meals supports muscle protein synthesis better than taking most of it in one sitting.
- Older adults are relatively resistant to the muscle-building effect of protein, which is why intakes above the basic reference value are commonly advised alongside resistance exercise.
- In established kidney disease, protein intake is often deliberately limited — do not raise it on the basis of a general calculator.
- Most people meet even the higher targets from food. Supplements are a convenience, not a requirement.
Evidence & validation
The 0.75 g/kg/day figure is the UK adult reference nutrient intake set in the Department of Health dietary reference values. Higher intakes in the 1.2-2.0 g/kg range come from sports nutrition consensus and position statements rather than from population dietary reference values, and are aimed at training adaptation and preservation of lean mass rather than at preventing deficiency.
Frequently asked questions
How much protein do I actually need?
The UK reference nutrient intake for adults is 0.75 g per kg of body weight per day. Higher targets of 1.2-2.0 g/kg relate to training and preserving muscle, not to preventing deficiency.
Can too much protein damage the kidneys?
In people with healthy kidneys there is no good evidence that higher intakes cause damage. In existing kidney disease, intake is often restricted on medical advice.
Do I need protein shakes?
Usually not. Shakes are a convenient way to hit a target, but ordinary food — meat, fish, eggs, dairy, beans, pulses, tofu, nuts — meets it just as well.
Is plant protein as good as animal protein?
Individual plant sources vary in amino acid profile, but a varied diet across pulses, grains, soya, nuts and seeds covers requirements comfortably.
Should I use my current weight or a target weight?
For most people current weight is fine. At high body fat levels, calculating on a target or lean body weight avoids inflating the figure.
References
- Department of Health. Dietary Reference Values for Food Energy and Nutrients for the United Kingdom (Report on Health and Social Subjects 41). 1991 — adult protein RNI 0.75 g/kg/day.
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