Ask this question in a gym and you’ll get a dozen different answers. Here’s the actual answer, based on what the research says.
The official number is too low
The Recommended Dietary Allowance 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.
What the research actually supports
A 2017 meta-analysis in the British Journal of Sports Medicine (49 studies, 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 a 170-pound 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.
What protein does
Protein is made up of amino acids — the building blocks your body uses to repair and build muscle tissue. When you train, you create small amounts of damage in your muscle fibers. Protein is what your body uses to repair that damage and come back stronger.
Beyond muscle: protein supports immune function, hormone production, and enzyme activity. It’s also the most satiating macronutrient, which helps manage body weight.
Does it matter when you eat it?
What matters most is your total daily protein intake, distributed reasonably throughout the day. Research suggests spacing protein intake across 3 to 4 meals is more effective than eating most of it in one or two sittings. About 30 to 40 grams per meal is a reasonable target.
What good protein sources look like
Animal sources tend to be most bioavailable: 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 more of them to hit the same functional protein intake. Lentils, beans, tofu, tempeh, edamame, and quinoa are the strongest plant-based options.
Protein powders are a convenient tool, not a requirement. If whole food sources are getting you to your daily target, you don’t need powder.
A simple way to start
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.
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 help with nutrition? Reach out about Nutrition Coaching at CrossFit Liminal.