For many years, bodybuilders have lived by the rule that you need to eat one gram of protein per pound of physique weight per day, otherwise you’re leaving good points on the desk.
Over the previous few years, although, many researchers and health influencers have backpedaled, claiming that the true threshold is 0.7 g/lb, and consuming greater than this can be a waste of energy and cash.
The principle piece of proof for this place was a 2018 meta-analysis from McMaster College. Scientists pooled the outcomes of 49 research with ~1,900 folks and located that muscle progress plateaued at about 0.73 g/lb of protein per day.
Right here’s what the outcomes appeared like:
And similar to that, the “1g/lb” rule sank just like the Bismark.
Or did it?
There are 3 causes you must take these examine outcomes with a grain of salt:
1. Each single examine on educated weightlifters discovered they gained extra muscle with protein intakes over 0.7 g/lb.
When the researchers zoomed in on individuals who truly lifted weights, they discovered that they gained extra muscle after they ate nearer to 1 g/lb of protein per day.
The authors of the paper wrote that, relating to individuals who carry weights, “… it could be prudent to suggest ~2.2 g protein/kg/d…,” precisely what bodybuilders have really helpful for many years (2.2 g/kg = 1g/lb).
2. The boldness interval was big.
A confidence interval is the vary the place the true reply doubtless falls. The narrower it’s, the extra exact the estimate. Consider it like estimating a time of arrival: saying somebody will arrive between 2:59 and three:01 is exact; saying they’ll arrive between 2:30 and three:30 is way much less useful.
On this case, the interval ran from 0.47 g/lb all the best way as much as 1.0 g/lb.
Put otherwise, the information truly confirmed that the “true” plateau is likely to be about half the previous bodybuilding suggestion . . . or precisely equal to it.
3. The consequence wasn’t statistically important.
The p-value—a quantity researchers use to evaluate whether or not a result’s decided by the examine intervention or random likelihood—got here in at 0.079. By most scientific requirements, that quantity needs to be under 0.05 to be thought of legitimate.
In different phrases, the information was too inconsistent to be assured within the outcomes.
Two more moderen meta-analyses additionally bolster the case for increased protein intakes.
A 2022 meta-analysis from the identical lab at McMaster College checked out 66 research involving over 2,600 folks and located that muscle mass and lower-body power solely meaningfully improved in individuals who ate at least ~0.7 g/lb of protein per day.
On this examine, 0.7 g/lb was the minimal required to see enhancements in muscle mass, not the ceiling for supporting progress.
Right here’s what the outcomes appeared like:
A 2020 meta-analysis revealed in Diet Critiques mixed knowledge from 105 research involving over 5,400 folks. It discovered that the muscle-building advantages of protein stored rising all the best way as much as about 1.4 g/lb, which was the utmost quantity consumed. The good points bought smaller as consumption rose, however they didn’t disappear.
Neither evaluation was capable of pinpoint the precise level the place muscle progress leveled off, however they each point out it’s increased than 0.7 g/lb.
One downside with meta analyses like these is that it’s laborious to regulate for variables like calorie consumption, variations in coaching, adherence, the trainee’s degree of expertise, and so forth.
That’s why it’s additionally useful to take a look at how the physique processes protein at a person degree.
Particularly, scientists can use numerous methods to estimate how a lot of the protein you eat is definitely used to construct and restore muscle, and the way a lot is oxidized (“burned”) for power. Typically talking, in case your physique is oxidizing massive quantities of protein, it means you’re consuming greater than you must assist muscle progress.
The gold customary for figuring out that is known as the Indicator Amino Acid Oxidation (IAAO) take a look at, and it includes giving folks various quantities of protein and seeing how a lot of it’s oxidized.
Three research have used this technique to estimate protein necessities in skilled weightlifters. The common requirement throughout all three was about 0.85 g/lb. However to cowl virtually everybody—not simply the common particular person—the estimate rises to about 1.07 g/lb.
In different phrases, whereas most individuals wanted about 0.85 g/lb to maximally assist muscle progress, some folks wanted considerably greater than this, and there’s no solution to know which group you belong to with out present process this sort of testing. These research additionally didn’t look at how components like complete muscle mass, calorie consumption, coaching depth and quantity, age, and so forth influenced the outcomes.
For instance, it’s potential that extra muscular, energetic folks, who practice more durable than most, may want extra protein. It’s additionally nicely established that you must eat extra protein when proscribing energy to keep away from muscle loss, and that individuals over age ~60 usually want extra protein to assist muscle progress than youthful folks.
A 2025 systematic assessment by Deakin College discovered that weight-reduction plan weightlifters usually wanted about 0.9 g/lb of protein to keep away from shedding muscle whereas in a calorie deficit. The leaner they have been, the extra essential hitting that concentrate on was.
As specialists like Lyle McDonald have identified for many years, many research on protein consumption solely measured muscle protein synthesis, however ignored different tissues in your physique that additionally want protein.
Your tendons, ligaments, and different connective tissues, your organs, your blood vessels, and even the mitochondria in your cells all want protein to restore and get well from train. It’s laborious to measure precisely how a lot, but it surely’s virtually definitely not zero.
On a sensible word, the distinction between 0.85 g/lb and 1 g/lb can be largely irrelevant. For a 180-pound man, it’s 25 grams of protein—about one scoop of protein powder. For a 120-pound lady, that’s the distinction between ~100 and 120 grams of protein—a cup of yogurt or a small hen breast.
So, given the paradox within the analysis and the sturdy theoretical arguments for erring on the facet of extra protein quite than much less, consuming near 1 g/lb of protein per pound of physique weight per day remains to be smart.
There are some circumstances the place you might need to eat barely kind of than this quantity, however that is simple to determine with a calculator like this one:
→ Protein Calculator for Weight Loss & Muscle Gain
For many energetic folks, although, 1 gram per pound of protein per physique weight per day is a brilliant beginning place.
