Some links on this site are affiliate links. If you purchase through them, we may earn a small commission at no extra cost to you. We only recommend products we believe in.
For most men over 40, 0.8g/kg is a survival floor, not a training target. I aim for 1.8g/kg most days, split across four meals, and treat the 200g-shake bro nonsense as the marketing fiction it is. Past 2.2g/kg the curve goes flat.
Ask most GPs how much protein you need, and they will probably quote 0.8 grams per kilogram of bodyweight. For a man weighing 85kg, that works out at 68g per day, roughly equivalent to two chicken breasts. If you are over 40 and doing any meaningful exercise, that number is likely leaving results on the table.
Where the RDA Comes From
The Reference Nutrient Intake (RNI) in the UK, and the equivalent RDA used internationally, was established to prevent protein deficiency in sedentary adults, not to support muscle maintenance in active, ageing men. These are different goals requiring different amounts.
The figure was calculated by measuring the minimum protein intake needed to achieve nitrogen balance in healthy adults, then adding a safety margin. It says nothing about optimal intake for muscle retention, training adaptation, or counteracting the physiological changes that come with age. Using it as a target for athletic or health performance is like using a car's minimum tyre pressure as your target inflation.
Anabolic Resistance Changes the Calculation
After 40, something called anabolic resistance becomes increasingly relevant. Muscle tissue becomes progressively less sensitive to the protein-derived signal that triggers muscle protein synthesis (MPS). Put simply, you need more protein to generate the same anabolic response that a smaller amount would have produced at a younger age.
This is not a minor adjustment. Research consistently shows that older adults require a higher per-meal protein dose to maximally stimulate MPS, and that distributing protein across the day becomes more important as a result. Getting protein right after 40 is both a quantity and a quality challenge.
What the Research Says
A systematic review and meta-analysis published in the Journal of the International Society of Sports Nutrition (Morton et al., 2018) examined protein intake across multiple resistance training studies and concluded that intakes of 1.6-2.2g per kg of bodyweight per day are optimal for supporting muscle mass and strength gains in adults who train.
This represents roughly double the standard RDA. For an 85kg man training three to four times per week, this means targeting between 136g and 187g of protein per day.
More recent work specifically examining older adults supports the higher end of this range. A review in the American Journal of Clinical Nutrition (Bauer et al., 2013) concluded that 1.0-1.2g/kg/day should be considered a minimum for older adults to support muscle health, with active individuals needing considerably more.
What About Men Over 65?
The data gets more specific for men in their mid-sixties and beyond, where sarcopenia (age-related muscle loss) becomes a clinically significant concern. Some researchers now argue for intakes approaching 2.5g/kg/day for older men actively trying to counteract muscle loss, particularly those with limited training capacity or recovering from illness.
A position paper from the PROT-AGE Study Group recommended 1.0-1.2g/kg/day as a minimum for healthy older adults and 1.2-1.5g/kg/day for those with acute or chronic illness. If you are 65 or older and training seriously, targeting 2.0g/kg is a reasonable and evidence-supported approach. If you are choosing between dairy and plant sources to hit these targets, my whey vs plant protein guide for men over 40 compares the leucine numbers head-to-head.
A Practical Example
For an 85kg man:
- RDA minimum (0.8g/kg): 68g per day
- Active adults target (1.6g/kg): 136g per day
- Serious training target (2.2g/kg): 187g per day
The difference between the RDA and the upper training target is substantial in practice. Hitting 187g of protein through whole food alone on a typical British diet takes real planning. It means including a meaningful protein source at every meal, not just dinner.
Spreading Your Intake Across the Day
Total daily intake matters, but so does distribution. Given the leucine threshold that must be crossed to maximally stimulate MPS in older men (approximately 2.5g leucine per meal), you need at least three meals each providing 35-45g of protein to reliably hit that threshold across the day.
A single large protein meal in the evening, which is common in British eating patterns, does not distribute the stimulus effectively. Research suggests that distributing protein evenly across at least three meals produces better MPS outcomes than skewing intake heavily toward one meal, even when total daily intake is the same — I've gone into the practical scheduling in protein timing for men over 40.
For reference, 40g protein per meal looks like: four large eggs plus two strips of bacon, or 175g of cooked chicken breast, or 200g of Greek yoghurt plus a 25g protein shake, or 150g of tinned tuna plus two eggs.
Food First, Supplements as Top-Up
Whole food sources should form the foundation of your protein intake. Chicken breast, beef, fish, eggs, Greek yoghurt, cottage cheese, and legumes are all solid choices with supporting nutrients that protein powders lack. For joints, skin and tendons, a daily scoop of collagen is a low-friction addition — I cover the products that actually verify their hydroxyproline content in the best collagen for men UK 2026 guide.
Where protein powder earns its place is in closing the gap when food alone falls short. A busy day, travel, or a training session that suppresses appetite can all make it harder to hit targets. A single 25-30g shake or adding protein powder to porridge or a smoothie is a practical and effective way to top up without much effort — my best protein powder UK 2026 picks cover the products worth bothering with. Add creatine into the same shake and you have the two supplements with the deepest evidence base for men over 40 in one cup.
For specific product recommendations, see our picks for the best protein powders for men over 40 in the UK.
1.6-2.2g/kg daily, spread across at least 3-4 meals each providing 35-45g of protein. Past 2.2g/kg the response curve flattens. Whole-food first, whey to plug genuine gaps.
For specific product recommendations, see our picks for the best protein powders for men over 40 in the UK.
