Do You Need More Protein After 40?

Probably a little more than the official minimum, though not because turning 40 changes anything overnight. UK guidance sets protein at 0.75g per kilogram of body weight a day, which comes to roughly 45g for women and 55g for men. That figure was set to prevent deficiency, not to keep muscle on an ageing frame. From the forties onwards, muscle mass tends to decline gradually unless something is done to hold onto it, and researchers working on ageing generally argue for intakes above that minimum, spread more evenly across the day. The authorised claim is simply that protein contributes to the maintenance of muscle mass. That wording is deliberately modest, and it is the honest place to start.

What actually changes in your forties

Very little, on any given morning. The change is slow and cumulative, which is why it goes unnoticed for years. Muscle tissue is constantly broken down and rebuilt, and in a young adult the two roughly balance. With age the rebuilding side becomes less responsive: the same meal and the same exercise produce a slightly smaller building response. Researchers call that anabolic resistance — a description of how the tissue behaves, not a diagnosis.

The effect compounds. Estimates vary, but a commonly cited figure is a loss of around three to eight per cent of muscle mass per decade from the thirties, accelerating later. Most of that is avoidable rather than inevitable: the biggest driver is not age but how much load the muscle is asked to carry. Which sets the priorities honestly — resistance training is what tells the body to keep the muscle, and protein is the raw material it uses. No amount of protein substitutes for the stimulus.

What the UK figure is, and why researchers argue with it

The UK Reference Nutrient Intake for protein is 0.75g per kilogram of body weight a day for adults. It is a population figure, set to meet the needs of nearly everyone, and it does its job: outright protein deficiency is rare in Britain. How that number is built, and how much food it represents, is in how much protein you actually need in a day.

The argument is about what the figure is for. Avoiding deficiency and keeping muscle into your sixties are not the same goal, and a minimum designed for the first is not automatically the right target for the second. Groups working on ageing and nutrition have for years suggested older adults do better on intakes nearer 1.0 to 1.2g per kilogram, higher again for people recovering from illness or doing serious resistance work. Those come from expert groups rather than government guidance — dietary practice, not health claims, and contested at the margins. For a 70kg person the gap between 0.75 and 1.1g per kilogram is about 53g against 77g a day: real, but not dramatic. Roughly a tin of tuna and a pot of Greek yoghurt.

What anyone is allowed to claim about protein

This is worth being precise about, because the gap between what the science discusses and what a label may print is wide. In Great Britain only claims on the authorised register may be used. For protein there are four, word for word:

Protein contributes to a growth in muscle mass
Protein contributes to the maintenance of muscle mass
Protein contributes to the maintenance of normal bones
Protein is needed for normal growth and development of bone in children.

Three things follow. First, those claims belong to the nutrient, not to any brand or format — they apply to a chicken breast, a tin of lentils and a tub of powder equally, provided the food qualifies as a source of protein, meaning at least 12 per cent of its energy comes from protein. Second, the word normal cannot be dropped or traded up: “maintenance of normal bones” is authorised, “stronger bones” is not. Third, there is no authorised claim on that register about ageing, age-related muscle loss, or protein doing anything for people over 40 specifically. So nobody may say it, and we do not.

There is also no authorised claim specific to whey. A long list of proposed whey-specific claims was assessed and rejected, which is why whey protein, when it is described properly, rides on the generic protein wording above and never on a claim of its own.

Spreading it out matters more than it used to

The typical British eating pattern is back-loaded: cereal or toast in the morning, something light at lunch, most of the day’s protein at dinner. That works well enough when the rebuilding response is sharp. When it is blunter, the research points towards an even spread — a decent amount at each of three meals rather than 10g, 20g and 50g.

“A decent amount” means roughly 25 to 30g per meal for most adults, which is less exotic than it sounds: three eggs and a slice of wholemeal toast, a tin of mackerel on a jacket potato, Greek yoghurt with nuts. Breakfast is where most people fall short, and it is usually the easiest meal to fix.

None of it requires a shake, as can you get enough protein without a shake went through in full.

Bones, and the limits of what can be said

Protein is a structural component of bone as well as muscle, which is why “protein contributes to the maintenance of normal bones” made the authorised list. That is the whole of the permitted statement. Bone density after 40, and particularly after the menopause, is a clinical subject involving calcium, vitamin D, weight-bearing exercise and individual risk factors — a conversation with a GP, not with a tub.

Where a powder honestly fits

A protein powder is a convenience, and it is worth being plain about that. Biotic’s Gain Whey Protein Isolate comes as a 2lb tub with 25g of protein and 5.5g of BCAAs per serving, in six flavours, filtered further than a concentrate so it is lower in fat and lactose. That is a description of the ingredient, not a promise about what it will do for you.

It earns its place in one situation: when the protein would otherwise not get eaten. A shake at eleven, on a day when breakfast was a coffee, adds 25g that would have been missed. What it does not do is improve an already evenly-fed day, and it is not why anyone keeps muscle into their sixties — the training is. On whether the separate amino-acid tubs are worth buying too, we looked at that in what are BCAAs, and do you need a separate supplement.

See the Biotic’s Gain human range

When to ask someone qualified

Speak to a GP, pharmacist or registered dietitian rather than working it out from an article if you are losing weight without meaning to, if your grip or the stairs have got noticeably harder over months, if you have kidney problems or any condition where protein intake is medically managed, if you are pregnant, or if you take medication and are unsure how a supplement fits alongside it. A dietitian is also the right person to ask for a figure based on your own body rather than an average.

More on the nutrient itself, and the authorised wording, on our protein guide.