It’s an age-old question: how much protein do you need for maintaining good health in general, and building muscle in particular?
The answers to this question are varied and downright confusing.
You’ll find recommendations that range from .36 grams of protein per pound (.8 grams of protein per kilogram) of body weight to 1 gram of protein per pound (2.2 grams of protein per kilogram) of body weight.
So where along that spectrum does the true amount of optimal protein consumption lie?
Well, it isn’t in fact a cut and dry matter, and depends on several factors like physical activity and age.
Below, we break down what the research says as to how much protein you really need to consume.
Protein’s Role in Building Muscle
We all know that protein builds muscle, but how does it do it?
Well, it involves a complex biochemical process that would require thousands of words to explain. The TLDR version is that dietary protein contains amino acids that your body uses to build muscle tissue. Your body can’t make these amino acids on its own, so you need to consume them through dietary protein. One amino acid (leucine) is essential in kickstarting your body’s muscle-building process, called muscle protein synthesis.
So dietary protein 1) provides the building blocks to build muscle tissue, and 2) tells your body to start building muscle tissue.
Again, this is a really dumbed-down version of what protein does. But it’s a good working mental model of dietary protein’s role in the muscle-creation process.
So How Much Protein Do You Need?
You’ve probably heard of the RDA — the recommended daily allowance for nutrient requirements as issued by the National Academy of Medicine.
The RDA for dietary protein intake is .36 grams of protein per pound (.8 grams per kilogram) of body weight.
That means that the recommended amount of dietary protein for a 200-pound man is 72 grams of protein.
That’s not a lot of protein.
Heck, if you eat a 8-ounce filet mignon for dinner, you’ll have consumed over 80% of your required protein intake for the day.
The RDA is a broad average for all adults; while it’s probably sufficient for sedentary, younger folks, research in the past decade has shown that physically active adults and older adults need way more of this macronutrient in their diets.
How Much Protein Do You Need If You’re Physically Active?
If you’re physically active — you run, lift weights, have a labor-intensive job, etc. — research from Professor of Kinesiology Stuart Phillips suggests that you need .59 grams to 1 gram of protein per pound (1.3 to 2.2 grams of protein per kilogram) of your body weight.
So if you’re a 200-pound man, that means you should be getting somewhere between 118 grams to 200 grams of protein a day.
Whether you go towards the low or high end depends on how hard you’re training and your age (more on that in a bit). If you’re lifting heavy and/or are older, you’ll want to skew to the higher recommended amount of protein.
How Much Protein Do You Need If You’re Obese and Trying to Lose Weight?
Determining protein consumption for individuals who are obese is tricky. You need to lower calorie consumption in order to lose weight, but high protein diets are useful when you’re dieting because 1) they’re satiating, and 2) they help preserve muscle mass while you’re in a caloric deficit.
So you’ve got to find a protein target that’s high, but not so high that you eat an excess number of calories, and struggle to get into a caloric deficit.
When my nutrition coach Gillian Ward works with obese individuals, instead of pinning an amount of protein to body weight, she just makes sure that protein comprises 25% to 30% of total calories. “This allows the client to focus on calorie reduction and ensure they have a balanced diet. I’ve found that a balanced diet will get more long-term compliance than a diet that’s mostly protein and hardly any carbs and fat,” she told me. “And long-term compliance is key in any weight loss plan.”
How Much Protein Do You Need If You’re Older?
As you age, your body becomes less responsive to protein. Basically, as you get older you need to consume more protein to kickstart muscle protein synthesis than you did when you were younger. Combine that with the tendency of older people to avoid strength training, and you’ve got a recipe for sarcopenia or muscle loss. And that’s a big problem. Research has shown that sarcopenia contributes to a host of health and quality of life issues. If you want to have a healthy and vibrant old age, you need to maintain your muscle.
The research has shown that the RDA for dietary protein (.36 grams of protein per pound of body weight) is severely inadequate for older adults (we’re talking 50 years and over). Stuart Phillips recommends at least .54 grams of protein per pound (1.2 grams per kilogram) of body weight. If you’re a physically active older adult, you should probably be consuming .72 to 1 grams of protein per pound (1.6 to 2.2 grams per kilogram) of body weight, depending on your physical activity level.
Can You Overdose on Protein?
Myths persist that consuming too much protein is bad for your kidneys or will weaken your bones. These myths are based on flawed studies done 40+ years ago.
Unless you have some sort of kidney disease, your body can’t overdose on protein. Studies have shown that healthy people can consume up to 4.4 grams of protein per kilogram of body weight. If you’re a 200-pound man, that means you could consume 400 grams of protein in a day and not have any problems.
So, no. You can’t overdose on protein.
Is More Protein Better?
Many young gym bros think, “Protein builds muscle, so the more protein I consume, the better.”
While megadosing on protein won’t destroy your kidneys, it won’t do anything to improve strength or muscle size. The research shows that consuming beyond the range of .59 grams to 1 gram of protein per pound (1.3 to 2.2 grams of protein per kilogram) of body weight does nothing extra for protein synthesis and muscle building. Your body simply doesn’t need any more than that, and will just get rid of the excess protein through your pee and poop. So when you “overdose” on protein, you’re literally flushing the money you spent on it down the toilet.
You’ve Given Me Ranges of Protein Consumption. How Do I Figure Out the Exact Amount I Need?
Sorry. There’s no magic formula that will give you the exact amount of protein you personally need. Every individual is different, which is why we’ve presented a range of recommended amounts.
You’ll have to figure out your ideal amount through trial and error.
For me, I’ve used 1 gram of protein per pound (2.2 grams of protein per kilogram) of body weight for a couple of years now, and that’s worked for me. These past few weeks, I’ve been experimenting with lowering the amount of protein I consume in a day to 1.8 grams of protein per kilogram of body weight. I haven’t noticed any difference in my performance in the gym. Still feeling strong and muscular.
Experiment with the ranges above and find what works best for you. If you’d like more guidance, hire a nutrition coach.
Where to Get Your Protein?
Whole foods like milk, yogurt, eggs, and meat are your best sources of protein. Not only are they high in protein, but they’re also packed with micronutrients your body needs for overall health.
If you can’t get enough protein from whole foods, consider taking a whey protein supplement. Check out our write-up on whey protein supplements here.
If you’re vegan or vegetarian, it’s possible to get the protein you need from plant-based protein sources. You just have to be more thoughtful about it. While animal-based proteins have been shown to elicit a more robust protein synthesis response compared to plant-based proteins, other studies have shown that as long as you’re getting enough protein in your diet (from a variety of sources to ensure you’re getting all the amino acids essential to building muscle), there isn’t too much of a difference in muscle strength and size between people who get their protein from plant-based sources and those who get it from animal-based sources.