Protein for fat loss and muscle gain: start at 1.6 g/kg

Start every client at 1.6 g/kg and let the check-ins move it

A client who trains and wants to gain muscle needs about 1.6 g of protein per kg of body weight a day. A client in a deficit who wants to keep that muscle while losing fat needs more, and the leaner they get the more they need. Protein for fat loss and protein for muscle gain is one question asked from two sides, and every source worth citing answers it with a range rather than a number.

Our recommendation: start every client at 1.6 g/kg of body weight and move it only when a check-in gives you a reason.

Muscle gain: the gains stop at about 1.6 g/kg

Morton and others pooled 49 randomised controlled trials with 1,863 participants for the British Journal of Sports Medicine in 2018, every one of them at least six weeks of resistance training with a protein supplement. Inside that set, 42 study arms covering 723 participants reported both daily protein intake and the change in fat-free mass, at intakes running from 0.9 to 2.4 g/kg a day. They fitted a two-phase model to find the point where more protein stopped buying anything.

Protein supplementation beyond total protein intakes of 1.62 g/kg/day resulted in no further RET-induced gains in FFM.

Read the interval before you write 1.62 on a plan. The break point carries a 95 % confidence interval of 1.03 to 2.20 g/kg a day and a p value of 0.079, which the authors themselves report as not statistically significant. Their reading of that width is that it may be prudent to recommend about 2.2 g/kg a day for someone who wants the last of the gains. So 1.6 is the middle of an honest estimate, not a cliff edge, and a client sitting at 1.4 is not being short-changed.

The same paper is blunt about the other end of the scale. Protein at the RDA of 0.8 g/kg a day, it says, appears insufficient for anyone who lifts and wants more strength and more lean mass. That is the number a client will find first, and it is a floor for the population rather than a target for a person who lifts twice a week.

Fat loss: the target goes up as the client gets leaner

A deficit is when protein starts to matter most, because muscle is what the deficit is trying to take. Helms and others reviewed the contest preparation literature for the Journal of the International Society of Sports Nutrition in 2014 and landed well above anything in the muscle gain research.

Within this caloric intake, most but not all bodybuilders will respond best to consuming 2.3-3.1 g/kg of lean body mass per day of protein...

What moves a client up that range is how lean they already are and how big the deficit is. The review says so directly, and the ISSN's 2017 position stand reaches for the same pair of numbers, saying that intakes of 2.3 to 3.1 g/kg a day may be needed to keep lean mass in resistance-trained people during hypocaloric periods.

Those two recommendations look identical and are not. Helms counts per kg of lean body mass. The ISSN counts per kg of body weight.

For a very lean client the two land close together. For a client at 95 kg and 35 % body fat, the bottom of the same range is 142 g one way and 219 g the other.

Every target we recommend, and the paper behind it

Body weight or lean body mass: write down which one you used

Take a client at 95 kg and 30 % body fat, so 66.5 kg of lean mass. The bottom of the Helms range, 2.3 g per kg of lean mass, is 153 g a day. The 1.6 g per kg of body weight that comes out of Morton is 152 g. Two routes, one plan.

Now move the body fat and watch them separate. At 12 % body fat the same 95 kg client carries 83.6 kg of lean mass, and 2.3 g/kg of that is 192 g. At 35 % they carry 61.8 kg, and the same rule gives 142 g. The body weight rule hands all three of them 152 g.

Lean mass is the better denominator for a client in a deficit, which is why Helms uses it, and it is only as good as the body fat figure you fed it. So write the denominator on the plan next to the number. Six weeks later, when the client is 5 kg lighter and you are deciding whether 150 g is still right, that note is the difference between a recalculation and a guess.

Spread it over three or four meals

The ISSN's 2017 position stand puts a single meal's useful dose at 0.25 g of a high quality protein per kg of body weight, or 20 to 40 g in absolute terms, and asks for those doses every 3 to 4 hours across the day. Each dose should carry 700 to 3,000 mg of leucine.

For an 80 kg client on 1.6 g/kg, the day is 128 g. Four meals of 32 g clears the 0.25 g/kg bar with room to spare, and it is four normal plates rather than a shake habit. A 60 kg client needs 96 g a day against a per meal floor of 15 g, so three meals of 32 g does the job.

Clients over 65 start from a different floor

The PROT-AGE study group, appointed by the European Union Geriatric Medicine Society, published its recommendations in the Journal of the American Medical Directors Association in 2013. For people over 65 it asks for an average daily intake of at least 1.0 to 1.2 g/kg of body weight, at least 1.2 g/kg for those who exercise, and 1.2 to 1.5 g/kg for most older adults living with an acute or chronic illness.

It also names the exception. Older people with severe kidney disease who are not on dialysis, meaning an estimated GFR under 30, may need to limit protein rather than raise it.

A nutrition coach sets targets and is not qualified to decide whether a client belongs in that group. When an intake form mentions kidney disease, pregnancy, a history of disordered eating, or a medication the client cannot name, the next step is their doctor or a registered dietitian, and the protein target waits until you hear back.

Calories are the budget the protein comes out of

Grams per kg gives you protein and nothing else. The rest of the plate is built from a calorie figure, and a protein target set without one produces a plan nobody can shop for. Setting a client's calories from their intake is the other half of the same sitting. We do protein first, because it is the number we defend, then fit fat and carbohydrate into what is left. The free macro calculator puts the two together: calories from Mifflin-St Jeor, protein in grams per kg, and fat and carbohydrate from what is left.

Four things move the number, and none of them is a new study

• The client is not hitting it. A 180 g target hit four days in seven is worse than a 150 g target hit every day. Lower the number to the one that gets eaten.
• Weight is falling faster than 1 % a week. Helms and others put the rate that protects muscle at 0.5 to 1 % of body weight per week. Past that, protein is the first thing to raise and the deficit is the second thing to cut.
• The client gets much leaner. The lean mass denominator shrinks while the percentage climbs, so the same rule now asks for more.
• The goal flips. A client who stops losing and starts gaining moves from the Helms range to the Morton one. How far the number falls depends on how lean they are: 40 g for the 12 % client above, nothing at all for the one at 30 %.

Doing this for twenty clients is where the evening goes

The arithmetic above takes a minute for one client. It takes an evening for twenty, every week, once you add the weigh-in that moves one of them and the six week review that moves three more. That is the job Peas & Pans was built to take off a coach's desk.

Start at 1.6 g/kg, write down which denominator you used, and let the check-in tell you when to move it.