Guides · Protein & Muscle
The Protein Guide: how much, what quality, and why it decides how you age
Protein is the most under-consumed lever in most people’s diet — and the research consensus is far higher than the RDA most food labels assume.
This cluster covers the numbers (g/kg by goal and age), the quality question (leucine thresholds per meal), and the long game: skeletal muscle as your metabolic retirement fund.
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Read the full series
Part 1
How much protein actually builds muscle — and why leucine pulls the trigger
Building muscle comes down to two numbers most people never track: how much total protein you eat per kilogram of bodyweight, and how much leucine lands in each meal. Misi plots both against the evidence.
Part 2
Protein quality, not just quantity — why leucine decides if a meal counts
Two meals can have the same protein on the label and do completely different things to your muscle. The difference is amino-acid quality — and above all, leucine. Here is how to tell, and how Misi tracks it.
Part 3
Protein, muscle and a longer life — why skeletal muscle is your retirement fund
Muscle is not just for the gym. It is metabolic reserve, fall protection and one of the strongest predictors of how well you age. And protecting it means raising your protein target as you get older, not lowering it.
Part 4
On a GLP-1? The muscle you must not lose
Semaglutide and tirzepatide strip weight fast — but a large share of it can be muscle, not just fat. Here is the protein-and-training protocol that protects lean mass, and how Misi tracks it.
Part 5
Menopause, muscle and bone — defending both with protein and lifting
The menopause transition accelerates the loss of muscle and bone — but the two most effective countermeasures are firmly within your control. Here is the protein-and-training case, and how Misi tracks it.
Part 6
The daily macro problem — hitting your numbers without a spreadsheet
Real food does not arrive in round numbers. Most days you finish 20g of protein short or a little over on carbs — and fixing it by hand is fiddly. Misi turns it into a single dial.
Part 7
Creatine is not just for muscle — the brain, ageing and the women’s case
Creatine is the most-researched supplement in sport — and the evidence now reaches well beyond the gym, into cognition, healthy ageing and women’s health. Here is what holds up, and one lab quirk Misi accounts for.
Part 8
Your muscles are an endocrine organ: what “myokines” actually do
Muscle isn’t just for movement. When it contracts, it releases signalling molecules called myokines that talk to your fat, liver, and brain — which is why building and using muscle changes your whole-body metabolism, not just your strength.
Part 9
Muscle is where most of your blood sugar goes
After a meal, the majority of the glucose you absorb is taken up by skeletal muscle. That makes trained, insulin-sensitive muscle one of the body’s most important defences against high blood sugar and type 2 diabetes.
Part 10
Muscle is your body’s reserve for illness and aging
Beyond movement and metabolism, skeletal muscle is the body’s main store of amino acids — a reserve it draws on during illness, injury, and recovery. That reserve is a big reason muscle mass predicts how well people withstand serious health challenges.
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Frequently asked
How much protein do I need per day?
For active adults, 1.6–2.2 g per kg of body weight daily is the meta-analytic consensus (Morton 2018). Dieting, older (60+) and GLP-1-using adults should aim for the upper end or beyond — up to ~2.4 g/kg — to preserve lean mass.
Does protein timing matter?
Distribution matters more than timing: aim for ~0.4 g/kg per meal across 3–5 meals, each clearing the ~2.5 g leucine threshold that triggers muscle protein synthesis.
Is high protein safe for kidneys?
In people with healthy kidneys, intakes well above 2 g/kg have repeatedly shown no adverse effect on kidney function. If you have existing kidney disease, protein targets should be set with your clinician — Misi tracks eGFR from your labs for exactly this reason.