Protein, and how much you actually need

Protein has become the marketing nutrient of the decade, added to products that never needed it and sold at a premium to people already consuming enough.

The reference intakes

Population recommendations sit at around 0.75 to 0.8 grams per kilogram of body weight per day for healthy adults, which is a minimum to prevent deficiency rather than an optimum.

Most people in higher-income countries comfortably exceed this without trying.

Where higher intakes are supported by evidence: older adults, where recommendations of around 1.0 to 1.2 grams per kilogram appear in expert consensus for preserving muscle mass; people undertaking resistance training, where around 1.4 to 2.0 grams per kilogram is commonly cited in sports nutrition guidance; during weight loss, to preserve lean mass; in pregnancy and lactation; and during recovery from illness or surgery.

Above roughly 2 grams per kilogram, additional intake produces no further benefit for muscle in the available evidence.

Distribution

A detail that matters more with age.

Muscle protein synthesis responds to a threshold amount of protein at a meal rather than to daily totals alone, and the threshold appears higher in older adults — a phenomenon described as anabolic resistance.

Which supports spreading intake across meals rather than concentrating it in the evening, which is the common pattern.

Practically: including a protein source at breakfast and lunch rather than only at dinner.

Sources and cost

Where the arithmetic favours the unglamorous.

Cheapest per gram of protein: dried pulses, eggs, milk, tinned fish, chicken thighs, tofu, oats and peanut butter.

Most expensive: protein powders, protein bars, protein-fortified snacks and lean cuts of red meat.

The premium on protein-labelled products is frequently substantial for an amount of protein that a couple of eggs would provide at a fraction of the cost.

Which makes reading the label for grams of protein per portion and dividing by the price a genuinely useful exercise.

Plant protein

Where the concerns are overstated and not baseless.

Individual plant proteins have varying amino acid profiles, and a varied diet containing pulses, grains, nuts and seeds across the day provides adequate amino acids without deliberate combining at each meal — the older advice about combining at every meal has been revised.

Plant proteins are generally less digestible than animal proteins, which is why some recommendations for people eating entirely plant-based are slightly higher.

Soya, quinoa and buckwheat contain all essential amino acids in useful proportions.

And vitamin B12 requires supplementation on a vegan diet, which is separate from protein and is essential.

Supplements

An honest assessment.

Protein powder is food in a convenient form, not a drug.

It is useful where meeting requirements from food is difficult — after surgery, with poor appetite, with high training volumes, or where convenience genuinely determines whether protein is consumed.

It offers no advantage over food for people already meeting requirements.

Whey, casein, soya and pea proteins all support muscle protein synthesis, with modest differences.

Third-party testing certification matters for anyone subject to drug testing, since contamination has been documented.

And protein bars are generally confectionery with protein added, at confectionery prices plus a premium.

Is more harmful

The common concern.

In people with healthy kidneys, higher protein intakes within the ranges discussed have not been shown to cause kidney damage.

In people with existing chronic kidney disease, protein intake is a genuine clinical consideration and should be guided by a clinician or renal dietitian.

Very high intakes displace other foods, which is the more realistic downside — a diet dominated by protein at the expense of fibre and plants is nutritionally worse overall.

And processed red meat has established associations with colorectal cancer, which is a reason to consider the source rather than only the quantity.

The practical version

What to actually do.

Include a protein source at each meal.

Use pulses, eggs, dairy, tinned fish and cheaper cuts as the backbone.

If you are over sixty or training with weights, aim towards the higher end of the ranges above.

Buy powder only if it solves a specific problem, and buy plain unflavoured versions which cost less.

Ignore protein claims on products that would not otherwise contain it.

And note that most people asking whether they need more protein are already eating enough, while the group who genuinely need more — older adults with poor appetite — are rarely the ones buying it.

General information only, not medical or nutritional advice. Consult a qualified dietitian about protein requirements, particularly if you have kidney disease.