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.
Anabolic resistance is the bit most men over 40 underrate. The 20g 'one shake' rule from your twenties is no longer enough; you genuinely need 35-40g per meal to fully stimulate synthesis. I treat it as a target, not a guideline.
Protein is the most important dietary variable for men over 40 who train. It drives muscle protein synthesis, prevents sarcopenia (age-related muscle loss), supports testosterone production, reduces SHBG, and keeps you satiated during any caloric deficit.
Most men eat far too little.
Why Protein Needs Are Higher After 40
Two mechanisms drive increased protein requirements with age:
Anabolic resistance: After 40, the muscle protein synthesis response to a given dose of amino acids is blunted compared to younger men. Where a 25-year-old might maximally stimulate protein synthesis with 20g of protein, a 45-year-old may need 30-40g to achieve the same response. You need more protein per meal to drive the same anabolic signal.
Higher baseline protein turnover: Muscle protein breakdown increases with age, meaning you need more incoming protein just to maintain nitrogen balance - before adding any for muscle building or retention during dieting.
The practical result: men over 40 who eat at the standard RDA of 0.8g/kg lose muscle progressively. The research-supported target for active men over 40 is 2.0-2.4g/kg/day.
Total Daily Target
For a 90kg man: 180-216g protein per day.
To put this in context:
- 3 large eggs = 18g
- 150g chicken breast = 45g
- 170g tin of tuna = 40g
- 200g Greek yoghurt = 20g
- 30g whey protein shake = 25g
Hitting 200g from food alone requires very deliberate planning. Protein supplementation is practical, not optional, for most men with this target.
Best Protein Sources
Animal Proteins (Complete - All Essential Amino Acids)
Chicken Breast (cooked)
Lean, versatile, cost-effective. 31g per 100g cooked. Buy frozen from Lidl or Aldi for best value.
g
protein
kcal
Whole Eggs
High in leucine - the primary trigger for muscle protein synthesis. Always eat the whole egg; the yolk contains cholesterol, zinc, and vitamin D.
g
protein
kcal
Oily Fish (Salmon)
Protein plus omega-3 EPA/DHA. Reduces systemic inflammation which suppresses testosterone.
g
protein
kcal
Cottage Cheese
High casein (slow-digesting) - ideal before bed to reduce overnight muscle protein breakdown.
g
protein
kcal
Chicken breast: 31g per 100g cooked. Lean, versatile, cost-effective.
Eggs: 6g per egg. High in leucine (the primary amino acid trigger for muscle protein synthesis). Eat the whole egg - the yolk contains cholesterol (testosterone precursor), zinc, vitamin D.
Beef (lean cuts): 25-30g per 100g. Also provides zinc and creatine. Choose sirloin, rump, mince (5-10% fat).
Oily fish (salmon, mackerel, sardines): 20-25g per 100g, plus omega-3 EPA/DHA. Best double-benefit protein source.
Greek yoghurt: 10g per 100g, plus casein (slow-digesting - good before bed to reduce overnight protein breakdown).
Cottage cheese: 11g per 100g. High casein, low calorie. Excellent pre-sleep protein.
Plant Proteins (Incomplete - combine for full amino acid profile)
Lentils: 9g per 100g cooked. Also provides iron and fibre.
Chickpeas/beans: 7-9g per 100g cooked.
Tofu: 8g per 100g. Complete protein. Fine in normal dietary amounts (see testosterone and diet article for soy concerns at excessive intake).
Edamame: 11g per 100g. One of the best plant protein sources.
Plant proteins are valuable but require higher quantities to hit leucine thresholds for muscle protein synthesis. If primarily plant-based, protein targets at the higher end (2.4g/kg) and leucine supplementation should be considered.
Men over 40 don't need complicated protocols. They need 35-40g of protein at every meal and a shake when they can't hit that from food.
Protein Timing
The research on protein timing has become more nuanced. Key practical points:
Per-meal dose: Aim for 30-40g per meal for men over 40 (due to anabolic resistance). Three to four protein-rich meals per day rather than one large serving.
Post-training window: Not as critical as once thought, but within 2 hours of training is optimal. Pre-training protein (30-40g) also works effectively.
Pre-sleep protein: 30-40g of casein protein before bed reduces overnight muscle breakdown. Greek yoghurt, cottage cheese, or a casein protein shake are all effective.
Breakfast: Don't skip protein at breakfast. Starting the day with a protein-rich meal (3 eggs + Greek yoghurt) sets up better protein distribution throughout the day.
Protein Supplements
Whey Protein (Fast-Absorbing)
Best for: post-training, any time you need a convenient protein hit.
Casein Protein (Slow-Absorbing)
Best for: before bed, between meals when you want sustained amino acid release.
The Testosterone Connection
Adequate protein intake directly supports testosterone through two mechanisms:
SHBG reduction: Higher dietary protein is consistently associated with lower SHBG in population studies. Lower SHBG means more free testosterone - the biologically active fraction. This is one reason high-protein diets often correlate with better hormonal profiles in active men.
Lean mass maintenance: Muscle mass drives testosterone. Sarcopenia (muscle loss with age) is associated with declining testosterone. Adequate protein, combined with resistance training, is the primary tool against sarcopenia.
Test your hormone panel alongside your nutrition changes. The difference in free testosterone between a 0.8g/kg and 2.2g/kg protein intake, combined with training, is often meaningful.
2.0-2.4g protein per kg bodyweight per day. 30-40g per meal (due to anabolic resistance after 40). Include casein before bed. Whey post-training. Food-first, but supplementation is practical for most men hitting these targets. Test your testosterone - protein intake affects SHBG and free T measurably.
Related: Best protein powder for men over 40 · Training programme for men over 40 · Testosterone and diet · Testosterone and weight loss
Affiliate disclosure: This article contains affiliate links. If you purchase through these links, Male Optimal earns a small commission at no extra cost to you. This does not affect recommendations.
