Protein is what your body uses to repair tissue, run your metabolism, and make many of the hormones and enzymes that keep you steady. You can’t store it the way you store fat or carbohydrate, so what you eat today really does matter. And it matters more as you get older: from your mid-30s you slowly lose muscle unless you work to keep it, and protein — paired with a little strength training — is one of the most useful things you can do about that.
Why it matters more as you age
The clearest reason is muscle. You lose it gradually as the years pass, and in later life the bigger losses have a name — sarcopenia, a condition tied to weakness, falls, and the slow loss of independence. The encouraging part is how much say you have in it. Eating enough protein alongside resistance training can slow that decline, and in many people partly reverse it.
Protein steadies your metabolism, too. It’s the most filling of the three macronutrients, which makes managing your weight feel less like a fight, and it softens the blood-sugar rise that follows a meal. There’s a nuance worth knowing: what protein replaces matters as much as how much you eat. Trading some refined carbohydrate for protein — especially plant protein — is the version most consistently linked to better metabolic health.
And it quietly supports your brain. Your body builds messengers like serotonin and dopamine from amino acids, the building blocks inside protein, and a few of those can only come from food. That’s useful context rather than a promise — mood and focus lean on far more than any single nutrient — but eating too little protein was never only a muscle problem. The same repair machinery keeps your skin, bones and immune system in good order whether or not you ever pick up a barbell.
Protecting muscle is central to healthy ageing. Protein and resistance training work together to help you do it.
How much you actually need
The adult RDA is 0.8 grams of protein per kilo of body weight a day. It’s designed to meet the needs of nearly all healthy adults — but it isn’t necessarily the most useful target for every age, activity level or goal. For most people who want to build or hold onto muscle, the evidence points higher: somewhere between 1.2 and 2.0 grams per kilo a day if you’re active, edging toward the top of that range if you train hard. Older adults belong at the higher end as well, since that’s precisely when protein does the most to defend muscle.
In everyday terms, a 70-kilo adult is looking at roughly 85 to 140 grams a day — noticeably more than most people eat without paying attention. The one exception worth flagging: if you have kidney disease, these general targets may not apply to you, so talk it through with your doctor first.
Where to get it, and when
Two things make a protein source worth leaning on — quality, meaning whether it carries the full set of amino acids, and quantity, how much you actually get per serving. Animal sources like lean meat, eggs, dairy and fish tick both boxes and count as “complete,” with oily fish such as salmon adding omega-3s on top. Plant sources — lentils, chickpeas, beans, tofu, tempeh, quinoa — cover any single food’s gaps when you vary them through the day, and bring fibre along for the ride. Protein powders sit in a category of their own: a genuinely handy top-up on a busy day, but never a stand-in for real food.
Timing matters less than the daily total, but it still helps. Spreading protein across your meals, rather than saving it all for dinner, gives your muscles repeated chances to rebuild through the day. Include a solid serving at each meal and something after you train, and don’t worry about a larger portion going to waste — your body still puts it to use. This is about steady habits, not strict rules.
Three myths worth dropping
The first is that high protein wrecks your kidneys. In people with healthy kidneys, higher-protein diets haven’t been shown to cause harm in the studies we have — though most are fairly short-term, and existing kidney disease is a genuine exception to raise with your doctor. The second is that protein is bad for your bones; if anything the reverse is true, since enough protein supports bone strength, especially with adequate calcium and some resistance training behind it. The third is that more protein automatically means more muscle — it doesn’t, because without the training stimulus and enough total food, the extra grams simply have nowhere to go.
The bottom line
Not many habits pay off across so much at once — muscle, recovery, physical function and metabolic health — and the fix here is refreshingly ordinary. Eat a little more protein than you do now, spread it through the day, lean on good sources, and add some strength training. Do that consistently and you’re investing directly in a stronger, sharper, more independent future you.
