How Much Protein Do I Need a Day?
The baseline is about 0.75 grams per kilogram of body weight, and most people already exceed it. Training, ageing and weight loss raise the useful amount. What the numbers mean.
In short
The UK reference intake is 0.75 grams of protein per kilogram of body weight a day, about 56 g for a 75 kg adult, and most people in the UK already eat more than that. People who train hard, are losing weight or are over 65 benefit from more, around 1.2 to 1.6 g per kilogram. Above about 2 g per kilogram there is little added benefit for most.
Protein has become the nutrient people worry about most and are least likely to be short of. Most adults in the UK comfortably exceed the official requirement without trying. The useful question is not whether you get enough, but whether you would benefit from more, and that depends on what you do.
The baseline
UK guidance sets the reference intake at 0.75 grams per kilogram of body weight per day. For a 60 kg person that is 45 g; for 90 kg, about 68 g. It is the amount that prevents deficiency in nearly everyone, not an optimum.
Average UK intake is well above it, at around 1.1 to 1.3 g per kilogram. Deficiency in healthy adults eating a normal diet is unusual.
When more helps
Resistance training. Muscle is built from protein, and people lifting weights or training hard benefit from roughly 1.4 to 1.6 g per kilogram. Beyond about 2 g there is little further gain in most studies.
Losing weight. Higher protein, around 1.2 to 1.6 g per kilogram, helps preserve muscle when eating in a deficit and is more filling per calorie than carbohydrate or fat, which makes the deficit easier to keep.
Over 65. Older adults process protein less efficiently and lose muscle faster, so guidance for that group has moved towards 1.0 to 1.2 g per kilogram, with resistance exercise alongside it.
Recovering from illness or surgery. Requirements rise, and clinical guidance sets specific targets.
What that looks like in food
Rough protein per typical portion:
- Chicken breast, 150 g: about 45 g
- Tin of tuna: about 25 g
- Two eggs: about 13 g
- Greek yoghurt, 170 g: about 15 g
- Lentils, cooked, 200 g: about 18 g
- Tofu, 150 g: about 18 g
- Milk, 250 ml: about 8 g
- Bread, two slices: about 8 g
A day with eggs at breakfast, a tuna sandwich at lunch, chicken and lentils at dinner and a yoghurt reaches over 110 g without effort. That comfortably covers a 75 kg person training hard.
Spreading it out
There is reasonable evidence that muscle responds better to protein delivered in several moderate doses, 20 to 40 g at a time, than to one large one. Breakfast is where most people fall short, since toast and cereal carry little. Adding eggs, yoghurt or milk there evens things out.
What does not hold up
- The idea that plant protein does not count. It counts. Combining sources over the day covers all the amino acids, and vegetarians and vegans reach targets easily with legumes, tofu, grains and nuts.
- The need for supplements. Powders are convenient and no better than food.
- Protein for its own sake. More than your activity level uses is simply calories, and expensive ones.
Work out your weight in kilograms, multiply by the figure that matches your situation, and check a normal day against it. Most people will find they are already there.
Common questions
Can you eat too much protein?
For healthy kidneys, intakes up to around 2 g per kilogram are well tolerated. The practical downside of very high intake is that it displaces other foods and costs more. People with existing kidney disease should follow medical advice on protein.
Do I need protein shakes?
Only if you struggle to reach your target from food. A chicken breast, a tin of tuna, a portion of lentils or a block of tofu each carry 20 to 30 g. Shakes are convenient, not superior.
Does timing matter?
Less than the total. Spreading protein across meals, with 20 to 40 g at each, appears to support muscle better than one large serving, but the daily amount is what matters most.
Sources
Every factual claim above traces to one of these. Follow them rather than taking this article's word for it.
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