How Much Protein Do You Actually Need?

The supplement most people underdo

It is the supplement most people get too little of, the official recommendation is a floor that gets mistaken for a target, and the shortfall widens with age, exactly when muscle matters most. This is one of the strongest single dietary lever worth nudging upward for healthy aging.

What protein actually does

Protein is the raw material your body builds and repairs itself from. Muscle above all, but also enzymes, hormones, immune cells, and the structure of skin and bone. Unlike fats and carbohydrates, the body keeps no real reserve of spare protein, so it has to arrive regularly from food.

The headline use, and the one with the strongest evidence, is muscle. And muscle is not just for strength or looks. It is a metabolic organ that helps clear blood sugar, protects you in a fall, and allows you to keep your independence as you age.

How much you actually need

The official recommendation, about 0.8 grams of protein per kilogram of body weight, is only enough to prevent deficiency in an average sedentary adult. It is a floor, not a target, and almost no one focused on muscle or healthy aging should settle for it.

How much higher to aim is best thought of as a ladder. Around 1.2 grams per kilogram of body weight is a reasonable baseline for general health, and about 1.6 grams per kilogram is the target for actively building and keeping muscle, the point where, across 49 studies in people who train, the benefit of more protein leveled off ^[1]. To skip the math, the table below turns those two targets into grams of protein per day at a range of body weights.

The official 0.8 g/kg floor would put that same 70 kg person at only about 55 grams a day, which shows how far below a useful target it sits.

Why it matters more as you age

As you get older, your muscles respond less to a given amount of protein, a blunting called anabolic resistance, which means older adults need more protein than younger ones, not less, to hold onto muscle ^[1]. An expert panel on aging recommends older adults aim well above the standard floor, at least 1.0 to 1.2 grams per kilogram, and toward the same 1.6 gram muscle target if they train ^[2].

This is not a minor point. Losing muscle with age, called sarcopenia, is one of the surest paths to frailty, falls, and lost independence. Combined with resistance training, creatine, and adequate protein is among the most powerful things you can do to keep the muscle that keeps you mobile. The training is not optional here. Protein supplies the bricks, but exercise is the signal to lay them; without the signal, the extra protein has no job to do.

Protein and staying lean

Protein also plays a critical role in body composition. Higher-protein meals increase fullness and the hormones that signal it, which makes eating well a little easier ^[3]. The more important benefit shows up when you are losing weight. A higher-protein diet helps you keep muscle while you shed fat, so more of what you lose is the fat you actually wanted to get rid of ^[3]. Protein is how you change your body composition, not just the number on the scale.

Food first, powder second

The best protein comes on a plate. Whole foods, meat, fish, eggs, dairy, legumes, and soy, bring protein along with nutrients a scoop cannot. Spread it across the day rather than saving it all for dinner. A solid serving of protein at each meal, roughly 25 to 40 grams, suits how your body uses protein better than one large hit.

Powder is a convenience, not a requirement. It earns its place when you struggle to reach your target from food alone, around training, or on a rushed morning, which is exactly where many people fall short.

If you want a marker that reflects your protein nutrition over time, albumin is the closest one on a standard panel, though it answers to your liver and your inflammation too.

How to choose a protein powder

The aisle is noisy, so keep it simple:

• Mostly protein, with little else. Look for around 20 to 30 grams a serving without a long tail of fillers, added sugars, or vague "proprietary blends."
• Third-party tested for heavy metals. This is the one that matters most, and it is not hypothetical. When Consumer Reports tested popular protein powders, more than two-thirds had more lead in a single serving than its experts consider safe for a day, and plant-based powders averaged about nine times the lead of dairy-based ones, with chocolate flavors worse still ^[4]. Lead and cadmium come from the soil the plants or feed grew in, so they concentrate when the protein is concentrated. Levels vary widely by product, which is exactly why you want one that carries independent testing such as NSF or Informed Sport certification, and why plant-based and chocolate powders are the ones most worth checking.
• Whey or a complete plant blend. Whey is well absorbed and rich in leucine, the amino acid that triggers muscle building. Plant-based eaters do best with a blend, such as pea plus rice, which covers the amino acids a single plant protein can miss.
• A taste you will actually use. The best protein is the one you take consistently.

The bottom line

Protein is the rare case where the honest advice is to aim higher than the label suggests, and higher still as you age. Build your meals around a real serving of it, push your daily total toward roughly 1.6 grams per kilogram if you are active, keep training so the protein has work to do, and reach for a powder only to close the gap that food leaves. Done consistently, it is one of the highest-return habits there is for staying strong, lean, and independent for the long run.