Why one physician sets protein targets well above the standard guideline, and what that means for everyday meals.
Muscle is easy to take for granted until it starts to go. From middle age onward, most people lose muscle mass and strength gradually, and the loss speeds up later in life. Peter Attia, a physician who focuses on preventive longevity medicine, treats muscle as one of the most important things a person can protect for the decades ahead.
The standard number is a floor
Most national guidelines set protein at about 0.8 grams per kilogram of body weight per day. Attia’s position is that this figure describes the minimum needed to avoid deficiency, and that it is too low for building and keeping muscle as we age. In his practice, he asks patients to aim for roughly 2 grams per kilogram, with about 1.6 grams per kilogram treated as a lower limit.
His reasoning is practical. Research on muscle building suggests the benefit flattens out somewhere around 1.6 grams per kilogram. Aiming a little higher means that on the days you fall short, you are still likely to land in a useful range.
How the protein is spread matters too
The body responds to protein meal by meal. Older adults in particular appear to need a larger dose at a single sitting to switch on muscle building, often discussed as around 30 to 50 grams of good-quality protein. Spreading protein across meals, rather than loading it into dinner, is one way to reach that dose more often in a day.
Protein is also only half of the picture. Attia pairs it with resistance training. Eating more protein without giving muscle a reason to grow does much less.
What this means in a kitchen
For a 70 kg adult, 1.6 to 2 grams per kilogram works out to roughly 110 to 140 grams of protein a day. That is a lot of food for many people, which is why protein-dense ingredients and simple, repeatable meals matter. Plant sources count, although they tend to deliver less protein per serving than animal sources, so portions usually need to be larger.
Higher protein intake supports muscle protein synthesis, and meta-analyses point to benefits up to about 1.6 g/kg per day in people who train.
The best target varies with age, body size, activity and kidney health. People with kidney disease should follow their doctor’s advice. The higher targets above come from one clinical practice, not a formal guideline.
Sources
- Peter Attia, MD. Optimizing protein quantity, distribution, and quality
- Peter Attia, MD. How much protein should you eat?
A study is not a product claim. This note summarises published work in plain language and is not medical advice. Peter Attia, MD is not affiliated with LIFTR and does not endorse our products. We link to this work because we learn from it.