How Much Protein Do You Need to Build Muscle After 40?
If you lift, aim for about 1.6 g of protein per kg of bodyweight a day (about 0.7 g per pound), which is where the research finds the extra benefit levels off. After 40, how you spread it matters too: get roughly 0.4 g per kg at each meal, which works out to about 25 to 40 g for most people, across three or four meals.
When people coming back to the gym get protein wrong, it's often not the daily total. It's eating almost none at breakfast and most of it at dinner.
What the research says about daily protein
A 2018 meta-analysis in the British Journal of Sports Medicine pooled 49 trials with 1,863 people who lifted weights, some with extra protein and some without. Gains in lean mass stopped improving at around 1.6 g per kg of bodyweight a day. The range around that estimate ran up to about 2.2 g/kg, so the authors suggested 2.2 g/kg as the top end for anyone who wants to cover every base.
The same review found the extra protein made less difference to lean mass as people got older. That's not a reason to eat less. It's a sign that older muscle responds less to protein, which brings us to how you spread it.
| Bodyweight | 1.6 g/kg a day | Per meal (0.4 g/kg) |
|---|---|---|
| 140 lb (64 kg) | About 100 g | About 25 g |
| 180 lb (82 kg) | About 130 g | About 33 g |
| 220 lb (100 kg) | About 160 g | About 40 g |
Anabolic resistance: why per-meal amounts matter after 40
As you age, your muscles need a bigger dose of protein to get the same building signal. Researchers call this anabolic resistance. In a 2015 study in the Journals of Gerontology, muscle building after a meal maxed out at about 0.24 g per kg in younger men but needed about 0.40 g per kg in older men. That's about 1.7 times as much per meal.
So a toast-and-coffee breakfast does little for an older lifter's muscles, and a 30 g breakfast does a lot more. Three or four meals that each clear that bar get more from the same daily total.
What 30 g of protein looks like
Approximate amounts per serving, from a Today's Dietitian protein chart. Check the label on packaged foods.
| Food | Serving | Protein |
|---|---|---|
| Chicken | 3 oz (85 g) cooked | 28 g |
| Steak | 3 oz (85 g) cooked | 26 g |
| Salmon or tuna | 3 oz (85 g) | 22 g |
| Greek yogurt | 6 oz (170 g) | 18 g |
| Cottage cheese, 1% | 4 oz (113 g) | 14 g |
| Lentils, cooked | Half a cup | 9 g |
| Skim milk | 1 cup | 8 g |
| Egg | 1 large | 6 g |
| Almonds | 1 oz (28 g) | 6 g |
Easy 30 g meals: 3 eggs plus a cup of milk; Greek yogurt with a handful of almonds and a glass of milk; a chicken or tuna sandwich; a steak or salmon dinner. Plant eaters can get there with lentils, beans, tofu and soy milk, just in bigger portions.
Protein chips, protein ice cream and other snacks
Protein snacks are having a moment. Search interest in protein chips grew 31% and in protein ice cream 40% over the past year, according to Glimpse.
They're fine as a convenience. A protein bar in your bag beats skipping protein at lunch. But build your day on whole foods first: meat, fish, eggs, dairy, beans. They come with fiber, vitamins and minerals, and they fill you up. And check the label for how many grams a serving really gives you.
How to start if you're coming back
- Week 1. Don't change anything yet. Write down roughly how much protein you eat at each meal for three days.
- Week 2. Fix breakfast first. Get it to 25 to 40 g with eggs, Greek yogurt, cottage cheese or milk.
- Week 3. Make lunch clear the same bar. Add a protein snack only if you're still short.
- Week 4. Check your daily total against the table above, and pair it with two or three strength sessions a week. Protein without lifting won't build much muscle.
For why lifting still works at any age, read the science of training after 40.
A week of protein plus strength
Three strength days, a protein-rich meal within a few hours of each one, and 25 to 40 g at every meal on every day, training or not.
| Day | Session | How long |
|---|---|---|
| Monday | Full Body A | About 45 min |
| Tuesday | Walk | 20 to 30 min |
| Wednesday | Full Body B | About 45 min |
| Thursday | Walk or mobility | 20 to 30 min |
| Friday | Full Body C | About 45 min |
| Saturday | Longer walk, ride or a sport | 30 to 60 min |
| Sunday | Rest | No session |
Full Body A, B and C each cover a squat, a hinge, a push, a pull and a carry or core move, in about 45 minutes. If you want the plan on paper, the 3 day full body workout guide lays out every exercise.
Give the protein something to build
Protein only builds muscle when you give it a reason, and Liftspan's free Fuel tab gives you a daily protein target to aim for. Full Body, 3 days is free in Liftspan: it's built for your equipment and around any joint you flag, every weight is set for you and moved up as you earn it, and each block ends with a lighter deload week. Rather use paper? Download the sheet.
Common questions
How much protein do I need to build muscle after 40?
About 1.6 g per kg of bodyweight a day (about 0.7 g per pound) if you lift. A large meta-analysis found gains in lean mass leveled off around that amount, with 2.2 g/kg as a reasonable upper end.
How much protein should I eat per meal?
Aim for about 0.4 g per kg of bodyweight per meal, roughly 25 to 40 g for most adults. Research found older muscles need about that much at once to get the full building response.
Is it bad to eat too much protein?
The 2018 meta-analysis suggested up to about 2.2 g/kg a day as an upper end for lifters. If you have kidney disease or reduced kidney function, ask your doctor before you increase your protein.
Are protein bars and protein chips worth it?
As a convenience, yes. They help on busy days. But whole foods like meat, fish, eggs, dairy and beans should do most of the work. Check the grams per serving on the label.
Do I need protein powder?
No. It's just a convenient way to add protein. If you can reach 25 to 40 g per meal from food, you don't need it.
Using Liftspan? See how your progress and log work in the help manual. New to it? Liftspan is a strength training app for lifters over 40 that builds your plan around your joints and moves the weight for you.
Sources: Morton et al. 2018, Protein supplementation and resistance training-induced gains in muscle mass and strength (British Journal of Sports Medicine) · Moore et al. 2015, Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men (Journals of Gerontology) · Today's Dietitian, Protein content of foods · Glimpse, protein chips · Glimpse, protein ice cream. General information, not a substitute for a clinician.
Keep reading: the science of training after 40 · 3 day full body workout · strength training on a GLP-1 · how to start working out again after a long break · all guides