The Least Amount You Need
What's the least amount of protein you can eat and still make gains? Here's what a recent meta-analysis says.
You know the general rule: For muscle and strength gains, lift weights and consume about a gram of protein per pound of body weight daily. Some people eat a little more and some a little less, but it's all good as long as you're in the ballpark.
But what's the least amount of protein you need to make strength gains? Hey, maybe you're on a budget, and food costs are getting crazy. Or maybe you're trying to fit other foods into your daily calorie allotment, like complex carbs, healthy but high-calorie fats like walnuts and avocados, or even a big pile of berries for their health benefits.
So, what's the rock-bottom amount of protein that'll get the job done? A new meta-analysis answers that question.
The Meta-Analysis
In this systematic review, researchers looked at 82 studies and compiled the data using all kinds of fancy math, like dose-response analyses with spline curves. Let's just jump straight to the answer in English:
For optimal strength gains when lifting weights, you only need 0.68 grams of protein per pound of body weight.
Here's exactly how the nerds wrote it:
"Muscle strength with resistance training increased by 0.72% (95% CI 0.40–1.04%) per 0.1 g/kg BW/d increase in protein intake up to 1.5 g/kg BW/d, but no further gains were observed thereafter."
In other words, lifters did gain more strength the more they increased their protein intakes, but only up to 0.68 grams of protein per pound of body weight. After that, the effects waned. Here's what that looks like with various body weights:
- 150 pounds: 102 grams
- 160 pounds: 108 grams
- 170 pounds: 116 grams
- 180 pounds: 122 grams
- 190 pounds: 129 grams
- 200 pounds: 136 grams
- 210 pounds: 143 grams
- 220 pounds: 150 grams
What Happens If I Eat More?
You'll be fine. While you won't drastically increase strength gains by exceeding 0.68 grams, that "extra" protein is still doing good things for your body.
For example, it's thermogenic and satiating, and it's very difficult for your body to store protein calories as body fat. Recent research even suggests that the only side effects of eating larger protein meals (up to 100 grams in one sitting) are prolonged protein digestion and amino acid absorption, which sustain muscle protein synthesis.
How to Use This Info
First, if you're used to eating closer to a gram of protein per pound, this meta-analysis teaches us that we don't have to panic if we get busy and have a "low protein" day and miss 50 or 60 grams. We'll still be fine in the strength gains department.
Second, it teaches many people that they're not getting enough protein to support muscle and strength gains. Outside of the hardcore lifting world, "experts" are still telling adults not to exceed 57 grams of protein per day. Those misinformed folks may need to double or almost triple that if they want their weight-training workouts to actually work.
Whatever your protein goals, remember that protein sources matter. Plant proteins don't do much for strength and hypertrophy unless you spike the heck out of them with leucine. Micellar casein and whey isolate (as found in MD Protein (Buy at Amazon)) are the best choices supplementally.
And remember that the meta-analysis above mostly looked at studies using basic protein foods and maybe some whey. Specialized proteins, like casein hydrolysate, increase muscle gains by 70% over whey. It's estimated that 20 grams of casein hydrolysate triggers more muscle growth than 30 or 40 grams of conventional protein.
So, if you only need 136 grams of protein to make strength gains (based on the research above), you may need even less if some of that is coming from casein hydrolysate-containing supplements like MAG-10 (Buy at Amazon).
Reference
- Tagawa. "Synergistic Effect of Increased Total Protein Intake and Strength Training on Muscle Strength: A Dose-Response Meta-analysis of Randomized Controlled Trials." Sports Medicine. 04 September 2022.