How your numbers are worked out

We start with your body: weight, height, age and sex go into the Mifflin-St Jeor equation, which estimates what you burn at rest. If your body fat has been properly measured (a DEXA scan or calipers), we use Katch-McArdle instead.

Then your day. Two concrete questions, how you spend most of it and how often you train, place you on one of 5 bands, from 1.4 to 2.05 times that resting figure. Two, rather than one about how active you feel: a single label invites everyone to pick the flattering one.

Then your goal. Losing sets a deficit held to 25% of what you burn, about the size of deficit at which a meta-analysis of training studies found muscle stopped growing; gaining sets a surplus capped at 600 calories. Protein lands between 1.6 and 2.4 g per kg of bodyweight, fat never drops below 0.6 g/kg, and on a cut carbs hold at 2 g/kg. Above a BMI of 30, those minimums are worked out for the weight your height carries at 30, or for your lean mass when your body fat was measured, so they cover the muscle you have. When your pace cannot fit inside those floors we stretch the timeline rather than cut the food, and no target drops under 1,200 calories for a woman, 1,500 for a man.

Your target is a range because a range is what it is. A figure from a questionnaire lands within 10% of what you actually burn for only a minority of people, so that is the band we show. Once we have learned from your weigh-ins it tightens to 7%, then 5%.

Edges round to the nearest 50 calories on purpose: a range printed to the last calorie reads like a measurement. Above a certain weight it carries one more line: Formulas run a little high at higher weights, so the band allows for it.

One weigh-in never moves your target. Bodyweight swings by a kilo on water and salt alone, so we read the trend, not the reading.

3 weigh-ins on separate days inside 21 days is the rhythm we ask for.

On Pro we compare what you logged against what your weight actually did over the last 21 days, and move the estimate towards your body rather than the equation.

It wants 10 genuinely logged days before it says anything, steps at most once every 7 days, and never moves your target by more than 100 calories at once, so a strange week bends the number rather than breaking it.

On a day you fast, protein is held at its full amount. Everything else bends around your window: about 350 calories per hour of eating, so an ordinary window changes nothing and only a short one with another fast the next day lowers it, never below 1,200.

We plan three sittings, not two: protein stops being useful past about 0.55 g/kg in one meal, the practical upper bound Schoenfeld and Aragon give, and a third keeps each under it. Where most of a week is a fast we hold any deficit to 15%.

We will not tell you that fasting lowers what you burn. The measured evidence, adults through Ramadan on doubly-labelled water, says expenditure is unchanged; what falls is how much people move. So a lighter fasting day is yours to choose, never ours to assume.

What this looks like on a real two-meal day is worked through in Ramadan calories and protein, and the plan that applies it is the Ramadan protein plan.

We carry 15, your day card scores the seven you choose, and a food’s percentage is quoted against the reference UK food labels print, the Nutrient Reference Value, so it matches the packet in your hand:

• Iron 14mg
• Vitamin D 5µg
• B12 2.5µg
• Zinc 10mg
• Magnesium 375mg
• Folate 200µg
• Calcium 800mg
• Selenium 55µg
• Potassium 2000mg
• Iodine 150µg
• Vitamin C 80mg
• Vitamin A 800µg
• Riboflavin 1.4mg
• Vitamin K 75µg

Where a food states its own figures, from a label, a barcode or a food database, we show them as declared. Where it states nothing we say so, and if we can estimate from a matching generic food we name it. You are always told which of the two you are reading.

A figure only appears where the source states one, and our sources are not equally complete. Measured across both generic food tables on 20 September 2026, the thinnest of the nutrients we carry is iodine: the UK table states it for 60% of its foods, the US table for 1%. Where your food came from the table that does not state it you see a blank, not a number we worked backwards from something else.

Your day is judged against something else: what UK guidance asks of someone your age and sex, the Reference Nutrient Intake. For adults under fifty-one, women first and men second:

• Iron 14.8 / 8.7mg
• Vitamin D 10 / 10µg
• B12 1.5 / 1.5µg
• Zinc 7 / 9.5mg
• Magnesium 270 / 300mg
• Folate 200 / 200µg
• Calcium 700 / 700mg
• Selenium 60 / 75µg
• Potassium 3500 / 3500mg
• Iodine 140 / 140µg
• Vitamin C 40 / 40mg
• Vitamin A 600 / 700µg
• Riboflavin 1.1 / 1.3mg

Omega-3 has no UK reference, so we show it in grams and judge no day by it. Pregnancy and breastfeeding raise a few of these, and where they do, the day says so.

Fibre is asked for in grams rather than as a share of a packet’s Daily Value. Your target is 14 g for every thousand calories your day asks for, held between 20 and 30 g. The top of that band is the UK adult recommendation, and we stop there on purpose: a bigger appetite does not make the published figure bigger, and on a bulk the fullness fibre brings works against what you are trying to do. Under sixteen we use the age bands the same guidance sets, which are stated flat rather than scaled.

A food that does not tell us its fibre is shown as a blank and counts for nothing, so a day’s figure is the least you had rather than all of it, and we say how many foods we could not read. We would rather leave a gap than fill it with a zero you would have to know to distrust.

Scan a barcode and we read the whole ingredient list, sub-ingredients included, name every ingredient worth checking and why, and say whether the pack is certified.

We never answer “halal” or “haram”. That is a ruling we are not qualified to give, and the additives where it matters most are the ones the packet does not source. We hand you the line and the reason; the ruling is yours.