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