The Protein Number That Actually Matters

For fifteen years the argument has been whether 1.6 grams of protein per kilogram of bodyweight is the real ceiling for muscle gain. A new pooled analysis of 49 randomised trials puts the question to bed, and the answer is more useful than a single number.

The benefit curve rises steeply to 1.6 g/kg, keeps climbing gently to about 2.2 g/kg, and then flattens hard. Below 1.2 g/kg, adding protein produces the largest measurable returns of any nutrition intervention we have. Above 2.2, the extra grams stop buying muscle and start buying expensive urine.

Distribution beats timing superstition

The tired advice to slam 40 grams within a 30-minute window is not wrong so much as irrelevant. Total daily intake and even distribution across three to five meals explain far more of the variance. Aim for 0.4 g/kg per meal, spread across the day, and the anabolic window widens to a door.

• Breakfast: 40 g — three eggs plus Greek yoghurt and a scoop of whey.
• Lunch: 45 g — 200 g chicken thigh, rice, whatever vegetables survive the fridge.
• Dinner: 45 g — 250 g lean beef or salmon with potatoes.
• Optional fourth meal: 25 g — cottage cheese before bed, if you train late.

What we would ignore

Collagen marketing, amino acid spiking claims and any product that lists protein in “proprietary blend” units. Buy plain whey, eat real food first, and treat every other supplement as a rounding error on top of a diet that already works.