How Much Protein Do You Actually Need?

Ask this question in a gym and you'll get a dozen different answers. The guy doing bicep curls will say a gram per pound of bodyweight, minimum. The internet will tell you to eat 200 grams a day. Your doctor might say you're fine with whatever you've been eating.

Here's the actual answer, based on what the research says — not what supplement companies want you to believe.

The official number is too low

The Recommended Dietary Allowance (RDA) for protein in the United States is 0.8 grams per kilogram of bodyweight per day. For a 170-pound person, that's about 62 grams.

That number is not a target. It's a minimum to prevent deficiency in sedentary adults. It was never designed to optimize health, support muscle building, or account for the needs of active people or older adults.

If you're exercising regularly and you're eating to the RDA, you're probably leaving a lot of adaptation on the table.

What the research actually supports

A substantial body of evidence — including a 2017 meta-analysis published in the British Journal of Sports Medicine that looked at 49 studies and over 1,800 participants — supports a range of 1.6 to 2.2 grams of protein per kilogram of bodyweight per day for people who are actively training for muscle growth or maintenance.

For a 170-pound (77kg) person, that works out to roughly 123 to 170 grams of protein per day.

That's a big gap from 62 grams. And it's why so many people who are working hard in the gym aren't seeing the results they expect — they're under-fueling their recovery.

What protein does

Protein is made up of amino acids, which are the building blocks your body uses to repair and build muscle tissue. When you train — particularly when you do resistance training — you create small amounts of damage in your muscle fibers. Protein is what your body uses to repair that damage and come back stronger.

Without adequate protein, that repair process is compromised. You can do everything right in the gym and still recover poorly, plateau, or lose muscle if you're not eating enough.

Beyond muscle: protein supports immune function, hormone production, enzyme activity, and dozens of other processes in the body. It's also the most satiating macronutrient — it keeps you full longer than carbohydrates or fat, which makes it useful for people managing body weight.

Does it matter when you eat it?

This used to be a bigger deal in fitness culture than it actually is. The idea of an "anabolic window" — the 30-minute post-workout period where you had to get protein or the workout was wasted — has been largely debunked.

What matters more is your total daily protein intake, distributed reasonably throughout the day.

That said, spacing protein intake across 3 to 4 meals does seem to be more effective for muscle protein synthesis than eating most of it in one or two sittings. Your body can only process so much at once — estimates vary, but research suggests about 30 to 40 grams per meal is about where you start seeing diminishing returns on muscle protein synthesis.

So spreading 140 grams across four meals of roughly 35 grams each is a reasonable approach. It doesn't need to be exact.

What about the "1 gram per pound" rule?

You'll hear this a lot. It's a round number that's easy to remember, and it's actually not bad advice for most active people. For a 170-pound person, that's 170 grams — which lands in the upper end of the research-supported range.

It's probably a little more than necessary for some people, but it's not harmful for healthy adults, and it gives you a buffer. If you're not hitting it every day, you're likely still fine.

Where it becomes unrealistic is for heavier individuals. A 250-pound person doesn't necessarily need 250 grams of protein. Recommendations are better calculated off lean body mass, not total weight, for people with higher body fat percentages.

What good protein sources look like

You don't need to overthink this. The best protein sources are ones you'll actually eat consistently.

Animal sources tend to be the most bioavailable — meaning your body can use a higher percentage of the protein they contain. Chicken breast, eggs, Greek yogurt, cottage cheese, tuna, salmon, beef, and milk are all solid options.

Plant-based sources work too, but you generally need to eat more of them to hit the same functional protein intake because they're lower in leucine (the amino acid most responsible for triggering muscle protein synthesis) and often less digestible. Lentils, beans, tofu, tempeh, edamame, and quinoa are the strongest plant-based options. Combining different plant proteins throughout the day helps cover any amino acid gaps.

Protein powders are a convenient tool, not a requirement. Whey is fast-digesting and well-studied. Casein is slower and works well before bed. Plant-based blends (pea + rice is common) are competitive with whey in recent research. If whole food sources are getting you to your daily target, you don't need powder.

A simple way to start

If tracking macros isn't your thing, here's a simple approach: build every meal around a protein source first. Aim for a palm-sized serving (roughly 25 to 35 grams) at breakfast, lunch, and dinner, and add one high-protein snack. That alone will get most people to an adequate daily intake without any counting.

Check in after a few weeks. If you're recovering better from workouts, maintaining or gaining muscle, and managing hunger more easily, you're probably in the right range.

Protein isn't magic. But it's one of the highest-leverage nutrition habits you can build — and most active adults are consistently undereating it.

Need some help or accountability around protein?  Reach out about Nutrition Coaching at CrossFit Liminal.