How Much Protein Do You Actually Need Per Day?
Almost every protein recommendation you have read is technically correct and practically useless, because it answers a different question than the one you are asking. The RDA prevents deficiency. You want body composition. Those are two different numbers.
In this guide
Two different questions
The Recommended Dietary Allowance for protein is 0.8 grams per kilogram of bodyweight per day. That figure gets quoted constantly as though it were a target, and it is not. The RDA answers the question “what is the least protein a sedentary adult can eat without going into negative nitrogen balance?” It is a deficiency threshold — a floor.
If you lift weights, are trying to lose fat without losing muscle, or simply want to feel full on fewer calories, you are asking a completely different question: “how much protein optimises my body composition?” That answer is roughly double the RDA, and it is one of the more settled findings in sports nutrition.
The short answer
1.6 g/kg of bodyweight per day if you are building muscle. 1.8 to 2.2 g/kg if you are losing fat while training. Below 1.2 g/kg you are almost certainly leaving results on the table; much above 2.2 g/kg you are buying insurance rather than results.
The numbers, by goal
Here is where each target comes from, with the research attached.
| Goal | Target | Evidence |
|---|---|---|
| Sedentary, avoid deficiency | 0.8 g/kg | The RDA. A floor, not a goal. |
| Active, general health | 1.2–1.4 g/kg | Comfortably supported; roughly what a varied diet with protein at each meal produces anyway. |
| Muscle gain | 1.6 g/kg | Morton et al. 2018 meta-analysis: 49 studies, ~1,900 participants. Benefits to lean mass plateaued around 1.6 g/kg. |
| Fat loss while training | 1.8–2.2 g/kg | Requirements rise in a deficit; higher intakes better preserve lean mass and improve satiety. |
| Aggressive cut, lean athlete | 2.3–3.1 g/kg of lean mass | Helms et al. 2014, for resistance-trained athletes dieting to very low body fat. |
| Adults over 60 | 1.2–1.6 g/kg | PROT-AGE recommendations; older muscle responds less to a given protein dose. |
The Morton meta-analysis deserves a sentence of its own, because it is the study most worth knowing. Pooling 49 randomised trials, it found that protein intake improved gains in lean mass from resistance training in a dose-dependent way — up to about 1.6 g/kg per day, after which additional protein produced no reliable further benefit. The upper bound of its confidence interval reached 2.2 g/kg, which is why many coaches advise eating toward that end as cheap insurance. What the data does not support is the 3 g/kg-plus intakes that circulate in bodybuilding circles.
Our protein target reference table converts all of these into total grams per day for every bodyweight from 45 to 125 kg, so you do not have to do the multiplication.
Bodyweight or lean mass?
For most people, total bodyweight works fine — that is what the studies used. It breaks down at higher body fat percentages, because fat tissue has almost no protein requirement. A 130 kg person at 40 percent body fat multiplying by 2.0 g/kg arrives at 260 g a day, which is neither necessary nor enjoyable.
Two fixes, both fine. Calculate from a realistic goal weight instead of your current weight, or estimate your lean body mass with our body fat calculator and multiply that by 2.0 to 2.5 g/kg. The two methods usually land within ten grams of each other, which tells you how much precision this decision really deserves.
Why you need more protein when dieting
This is counterintuitive: you eat less food overall but need more protein specifically. Three reasons.
- Amino acids get burned for fuel. When energy is scarce, some dietary protein is diverted to meet energy needs rather than to building and repairing tissue, so more input is required to achieve the same net effect.
- Muscle protein synthesis is blunted. A caloric deficit reduces the anabolic response to both training and protein, which raises the dose needed to maintain lean mass.
- Satiety and the thermic effect. Protein is the most filling macronutrient per calorie and the most expensive to digest — roughly 20 to 30 percent of its energy is spent on processing it, against 5 to 10 percent for carbohydrate and 0 to 3 percent for fat. On a 2,000-calorie diet, shifting 100 g of carbohydrate to 100 g of protein nets you a small but free increase in expenditure and a substantially less hungry afternoon.
The practical version: when you start a cut, protein goes up in grams even as calories go down. If you are working out your macro split, our macros calculator sets protein first and fills the remainder with fat and carbohydrate, which is the right order of operations.
Does timing and distribution matter?
Total daily protein is the dominant variable, and it is not a close contest. The “anabolic window” — the idea that you must consume protein within 30 to 60 minutes of training — has not held up well; studies controlling for total daily intake find the window is measured in hours, not minutes.
Distribution is a genuine second-order refinement. Each feeding appears to stimulate muscle protein synthesis up to a ceiling of roughly 0.4 g/kg per meal, beyond which the extra protein is still used — just not for that purpose. So three to five meals of 25 to 40 g each is a more effective pattern than 20 g at breakfast and 100 g at dinner. If you eat once or twice a day and hit your total, the difference is small enough to ignore.
Two details worth the effort: include a protein-containing meal reasonably close to your training session, and consider 30 to 40 g in the evening, since overnight is your longest fasting window.
Hitting the number in real food
For a 75 kg person aiming at 150 g a day, here is what that looks like — and it is less than people expect.
| Food | Portion | Protein |
|---|---|---|
| Chicken breast, cooked | 150 g | ~46 g |
| Greek yoghurt, 0% fat | 200 g | ~20 g |
| Whey protein | 1 scoop (30 g) | ~24 g |
| Eggs | 3 large | ~19 g |
| Tinned tuna | 1 tin (110 g drained) | ~26 g |
| Lentils, cooked | 200 g | ~18 g |
| Tofu, firm | 150 g | ~24 g |
| Cottage cheese | 200 g | ~22 g |
Two of those rows and you are a third of the way there. The usual failure mode is not that 150 g is hard — it is that breakfast and lunch contribute almost nothing, leaving an impossible dinner. Put 30 g of protein in every meal and the total takes care of itself.
If you eat plant-based, aim roughly 10 to 20 percent higher, since plant proteins are generally lower in leucine and slightly less digestible. Combining sources across the day handles the amino acid profile without any special planning.
Is high protein safe?
In people with healthy kidneys, yes, as far as the controlled research goes. Trials of intakes in the 2 to 3 g/kg range — some running more than a year in resistance-trained subjects — have not found impairment of renal function or bone health. The persistent worry about protein damaging kidneys derives from research on people who already have kidney disease, where protein restriction is a legitimate clinical treatment. Extrapolating that to healthy people is a category error.
Two honest caveats. If you have any diagnosed kidney or liver condition, this article is not for you — speak to your doctor, and read our medical disclaimer. And higher protein intakes require more fluid, so drink accordingly.
Set the number once, hit it most days, and stop thinking about it. Protein is the macro where getting it approximately right beats optimising it precisely.
Common questions
For healthy kidneys there is no established harm at the intakes studied, up to roughly 3 g/kg. The practical cost is opportunity: protein calories displace carbohydrate and fat, which fuel training and support hormone production. Very high protein diets tend to make lifting feel worse without improving body composition.
No. It is convenient, cheap per gram, and easy to digest, which makes hitting a high target simpler — but whole food protein works identically. Powder is a tool, not a requirement.
All of it gets absorbed; the ceiling is on how much stimulates muscle protein synthesis at once, around 0.4 g/kg per meal. Above that the surplus is used for other purposes rather than wasted, which is why one large protein meal is suboptimal but not pointless.
Per gram it is slightly less effective, being generally lower in leucine and marginally less digestible. Eating 10 to 20 percent more total protein and varying your sources across the day closes the gap comfortably.
Indirectly but meaningfully. It is the most satiating macronutrient per calorie, it has the highest thermic effect at 20 to 30 percent of its energy spent on digestion, and it protects lean mass in a deficit so that more of what you lose is fat.
Last reviewed September 14, 2026. Sources are cited inline; see our editorial policy for how we choose and review them.