How many calories
to lose weight, in the UK.
The NHS uses a simple working number: a 600 kcal daily deficit averages roughly 1lb of fat loss a week. Work out your maintenance first, subtract 600, log the food. That's the whole shape of it. The fine print is below.
BMR plus activity,
minus 600.
Two steps. Your Basal Metabolic Rate (energy at rest) times an activity multiplier gives your total daily energy expenditure (TDEE). Subtract a 600 kcal deficit and you've got your weight-loss target.
BMR, Mifflin-St Jeor
The standard estimate.
Men: (10 x weight kg) + (6.25 x height cm) - (5 x age) + 5.
Women: (10 x weight kg) + (6.25 x height cm) - (5 x age) - 161.
Worked example: a 35-year-old woman, 70kg, 165cm: (700) + (1031) - (175) - 161 = 1395 kcal BMR.
Activity multiplier
Sedentary (office job, no exercise): BMR x 1.2.
Lightly active (1 to 3 sessions a week): x 1.375.
Moderately active (3 to 5 sessions): x 1.55.
Very active (6 to 7 sessions, physical job): x 1.725.
Most people overestimate. Pick the lower one if you're in doubt.
The 600 kcal deficit
NHS guidance: a 600 kcal daily deficit averages roughly 1lb (0.45kg) of fat loss a week, sustainable for most adults. Bigger deficits go faster but are harder to stick to and risk skimping on vitamins and minerals.
The worked target
Our 70kg woman, lightly active: 1395 x 1.375 = 1918 kcal maintenance. Minus 600 = 1318 kcal a day for weight loss. That's the number to log against. Not 1200, not 800: those are diet-culture numbers, not NHS ones.
1318 kcal,
in the real world.
A day at the worked target. Not a meal plan, just a worked example showing the numbers add up.
Breakfast. 50g oats, 250ml oat milk, 80g blueberries. UK NRV: iron 18 percent, fibre 4g.
Lunch. Wholemeal wrap, 80g tuna, 1 tbsp light mayo, salad. UK NRV: vitamin B12 64 percent.
Snack. UK NRV: vitamin E 53 percent, magnesium 21 percent.
Dinner. 130g chicken breast, 60g (dry) rice, 100g broccoli, 1 tsp olive oil.
Day total: 1318 kcal. Protein 95g, fat 38g, carbs 145g. Vitamins and minerals broadly close to NRV. We log each scan against the day automatically.
Easy mistakes,
worth avoiding.
Things that derail a 600 kcal deficit faster than the deficit itself.
Going too low
Targets under 1500 kcal for men and 1200 kcal for women come with NHS warnings: harder to hit micronutrient targets, harder to stick to, risk of muscle loss. The 600 kcal deficit exists because it works.
Ignoring drinks
A pint of lager is roughly 180 kcal, a 250ml glass of white wine roughly 175, a flat white made with full-fat milk roughly 120. Three drinks a week can swallow a third of your daily deficit.
Forgetting cooking fats
1 tbsp olive oil is around 120 kcal, 10g butter around 75. They don't appear on a shopping list as a "meal" but they go into the pan. Worth logging the spoon, not just the chicken.
Trusting one bad day
NHS-style targets average over the week, not the day. Eating 200 kcal over once isn't the problem; reading that as a failure and eating 2000 over to compensate is.
Honest line
on medical territory.
We track and surface. We don't diagnose, we don't prescribe. There are situations where the right next step is a GP appointment, not a calorie app.
Weight steady or rising on a sustained deficit, weight loss without trying, or a BMI outside the healthy range. NHS GP first.
Diabetes, thyroid issues, PCOS, pregnancy, on medication that affects appetite or metabolism. Speak to your GP before starting a deficit.
Calorie tracking can be a trigger. Speak to a clinician (Beat: 0808 801 0677) before installing any tracker.
Under-18s on a deliberate deficit need clinical guidance. We don't market the app to under-16s.
Frequently
asked.
From the support inbox and the App Store reviews.
NHS guidance: an average daily deficit of around 600 kcal for roughly 1lb (0.45kg) of fat loss a week. Work out maintenance (BMR x activity), subtract 600, that's the target. See your GP before starting if you have persistent weight issues or a medical condition.
Basal Metabolic Rate, the energy your body uses at rest. Mifflin-St Jeor is the standard estimate: men: (10 x weight kg) + (6.25 x height cm) - (5 x age) + 5. Women: (10 x weight kg) + (6.25 x height cm) - (5 x age) - 161.
Sedentary x 1.2, lightly active x 1.375, moderately active x 1.55, very active x 1.725. Most people overestimate; pick the lower one if in doubt.
A larger deficit gives faster loss but is harder to sustain and risks muscle loss and low vitamin and mineral intake. The NHS 600 kcal figure exists because it's sustainable. If you have a clinical reason for faster loss, see your GP or a registered dietitian.
Yes. Enter age, weight, height and activity level and we estimate maintenance calories and set a daily target. We log every food you scan or type against that target, plus macros and (on Pro) vitamins and minerals against UK NRV.
Log a day,
see the number,
see where it went.
Free download. Up to 25 food logs a day on the free tier. Pro £3.99 a month or £34.99 a year for AI Coach, workouts and the vitamin and mineral side.
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