The weekly grocery run: one trolley, seven days, six targets

Most bad weeks are lost on a Sunday afternoon, in a supermarket, without a list. You buy food you like rather than food that hits a number, and by Wednesday the fridge can no longer produce a meal that fits your targets.

So here is the run, in aisle order, with quantities for one person for seven days. It takes about thirty-five minutes and it is the highest-leverage half hour of the week.

Start with the arithmetic, not the recipes

Protein is the binding constraint. Everything else in the trolley is flexible. At a goal weight of 150 lb your target is 150 grams a day, which is 1,050 grams across seven days — and that total is what you are actually shopping for.

Rough raw numbers, from USDA composition data: chicken breast carries about 23 grams of protein per 100 grams raw, 5% beef mince about 21, a drained tin of tuna about 25, an egg about 6, and 0% Greek yoghurt about 10 per 100 grams. Multiply pack sizes until the week clears your total. That is the entire exercise.

Do the sum once, before you leave the house, and write the total at the top of the list. Get the protein right and the rest of the trolley looks after itself, because carbohydrate and fat are the flexible rows of the swap table and protein is the row that is not.

The perimeter: protein first

Walk the outside of the shop before you touch the middle. The protein counter, the produce section and the dairy fridge are on that perimeter, and they hold roughly eighty per cent of what you need.

For a 150-gram-a-day target, this basket clears the week with room to spare:

• 1.4 kg chicken breast or turkey breast — the backbone of four dinners and two lunches
• 800 g of 5% beef mince or turkey mince, for the meals that need to be fast
• Four salmon fillets or six tins of tuna in water, for the two oily-fish days
• Two dozen eggs, half of them destined to be boiled on prep day
• 1.5 kg of 0% Greek yoghurt and a 500 g tub of cottage cheese, which together cover breakfasts and the 9pm problem

Produce: buy volume, not garnish

The most common shopping error on a cut is treating vegetables as a side. On this program they are the mechanism that makes a lower calorie target survivable — high water, high fibre, high chew, very few calories per plateful.

Buy more than looks sensible. Two bags of spinach, a kilo of frozen broccoli or green beans, six peppers, 500 g of mushrooms, two cucumbers, a bag of tomatoes, onions and garlic, two bags of leaves, and whatever fruit you will actually eat. Frozen is not a compromise here — it is picked and frozen quickly, keeps for months, and removes the Thursday wilt problem entirely.

Split it by shelf life as you load the trolley. Leaves and berries get eaten in the first three days, peppers and broccoli hold the middle of the week, and frozen carries Friday onward. Buy a week of fresh produce with no plan for the order and roughly a third of it goes in the bin on Sunday.

“You are not buying meals. You are buying a week in which the right meal is always the easiest one to make.”

Two lanes of the middle aisle

The middle of the shop is where the trolley usually goes wrong, so restrict yourself to two lanes and skip the rest. Lane one is carbohydrate: 1 kg of potatoes, 500 g of oats, rice or microwave rice pouches, a wholemeal or seeded loaf, and a bag of lentils or a few tins of beans.

Lane two is fats and flavour: olive oil, a 200 g bag of nuts, two avocados if they are ripe, and then the entire flavour budget — mustard, hot sauce, soy sauce, vinegar, lemons, spice mixes, tinned tomatoes, stock cubes. Flavour is nearly free in calories and it is what keeps the same six ingredients from becoming unbearable by day twelve.

Everything else in the middle of the shop is optional, and most of it is on the hidden-calories list in your playbook — granola, cereal bars, flavoured yoghurts, creamy dressings, juice and smoothies. None of them are banned. They are simply expensive in a currency you are short of this month, so they get bought deliberately or not at all.

The run itself

Order matters less than pace. Go once, go with the list, and go after you have eaten — shopping hungry reliably changes what ends up in the trolley.

The swap table in your playbook makes the whole thing forgiving. If the chicken is expensive this week, buy the mince. If the salmon looks tired, buy tinned. Anything in a row of that table exchanges for anything else in the same row, which means the list bends without breaking.

• Shop once. A second midweek trip is where the unplanned items get in
• Substitute within a swap-table row rather than abandoning the plan
• If the budget is tight, mince, eggs, tinned fish, frozen veg and oats carry the week on their own
• Anything you cannot eat in three days goes straight to the freezer on the way in, not after it turns