Your stomach runs at pH 1.5. That is more acidic than: - A wolf, at about 2 - A lion, at about 2 - Your dog, at about 2 - Nearly every animal that kills its own dinner It is the same as: - A vulture, at 1 to 1.5 - A hyena, at 1.5 - The animals that eat what has been dead for days That is the tell. Humans did not join the meat-eaters as hunters. We joined as scavengers. Two and a half million years ago we were turning up at the lion's kill forty hours late, with a rock, to open the bones nothing else could and eat what was left. The meat was days old. It was warm. It was alive with everything a carcass grows in the sun. So we built an acid bath. Strong enough to kill what lives on rotting flesh. Strong enough to strip protein that had already started to break itself down. Strong enough to take marrow out of a femur a hyena had given up on. That acid is still in you, at full strength, waiting for a carcass that never comes. It was never built for a leaf. A cow has four stomachs and two days to break down grass. You have one stomach, running at battery-acid strength, and a colon a quarter the length of a chimp's. Which is why the steak that has been in the back of the fridge since last Tuesday goes down without comment. And a bagged salad from a sandwich chain put 211 people in hospital in one summer. You are a scavenger with forward-facing eyes and a gym membership. Your stomach has known what you are the whole time. Somebody just needs to tell your plate.

"Carnivore is expensive." It is. Just not for you. The supplement company loses the multivitamin, the fish oil, the magnesium, the vitamin D, the probiotic and the fibre sachet. Forty pounds a month, gone, and after twenty years of loyal service you didn't even leave a note. The cereal manufacturer loses breakfast. Not a smaller box. The entire meal, every morning, for the rest of your life. Somewhere a tiger in a scarf is updating his CV. The snack aisle loses the 11am biscuit, the 3pm crash and the thing you buy at the petrol station because you are suddenly ravenous at a Shell garage. All three vanish the week your blood sugar flattens out, which was never in the business plan. The seed oil industry loses a customer who bought it twice over, once in the bottle and once hidden inside everything else on the shelf. They were quite proud of that second one. The pharmacy loses the antacid, the laxative, the ibuprofen for your joints and the paracetamol for the headaches you had assumed were simply your personality. Your surgery loses the seven-minute appointment about the reflux, and the repeat prescription that was booked in to renew itself quietly until roughly 2039. The diet industry loses the app, the subscription, the points, the meal replacement shake and the January relapse the entire model is built on. You have effectively cancelled Christmas for them. The coffee shop loses the pastry, because you stopped wanting it, which is somehow the most offensive part. The supermarket loses two thirds of its floor space. You now shop from one counter and walk past the rest of the building like it owes you money. Add up what leaves the bill and the meat has paid for itself several times over before you have eaten a single bite of it. They are not wrong that somebody is losing money here. They are just very careful never to say who.

Every instruction your generation was given after sixty made you weaker, and every one of them came from somebody who had never lifted anything. What they told you: - Take it easy (a decade of muscle you never replaced) - Do a class, it's more sociable (an hour of moving, nothing that loads) - Cardio is what protects the heart (a heart that copes, a body that shrinks) - Keep it light, protect the joints (joints that weaken without the load) - Mind your back (a spine nothing has loaded since the removal van) - Machines are safer than free weights, but only on the low settings And if you made it as far as the weights, they handed you a five kilo dumbbell and said fifteen reps. Light and high, for tone. A weight you could lift forty times, prescribed to a body that has been shedding muscle since it was forty. Because that part is real. From about forty you lose muscle every year, bone thins, and the loss accelerates after sixty whether you like it or not. That is the tide. There is exactly one thing that reverses it, and it is not a class and it is not a walk. It is lifting a weight that is genuinely heavy for you. Nothing else comes close, and nothing else has ever come close. Nobody is frightened of getting old. They are frightened of becoming somebody else's arrangement. What you should have been told: - Pick something up that is genuinely heavy for you - Six reps, not fifteen, because the load is the point - Make it heavier than last month - Twice a week, for the next twenty years It never reached a nine-minute appointment because there is no code and no budget for making a sixty-five-year-old strong, and a class can be run by somebody who has never picked anything up. A generation was talked out of its own body. You cannot get those years back. You can pick something heavy up on Monday and spend the next twenty years lifting the grandchild instead of being helped out of the chair.