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Targets

How we work out your targets

When you set up Know My Meals, we suggest a daily calorie target and how much protein, fat and carbs to aim for. Here is exactly how, so nothing is hidden. You can try it with your own numbers.

1. Calories at rest

First, we estimate how much energy your body uses just to keep running: breathing, keeping warm, thinking. We call this your calories at rest. We use the Mifflin-St Jeor equation, which works from your weight, height and age:

10 × weight in kg + 6.25 × height in cm − 5 × age
then +5 if you chose male, −161 if female, or −78 (halfway between) if other

Why this one? When researchers compared the common equations against real measurements, this one was most often close to the true number.

2. Your activity level

Next, we multiply by a number for how active your days usually are. The result is roughly what you’d eat to stay the same weight.

What you pickedWe multiply by
Mostly sitting: under 5,000 steps a day1.4
Fairly active: 5,000 to 15,000 steps, or regular workouts1.6
Very active: over 15,000 steps, or hard training most days1.8

These numbers come from international studies that measured how much energy people with different lifestyles actually use.

3. Lose or gain

If you want to change your weight, you pick a pace, as a share of your body weight per week:

PaceLoseGain
Gentle0.25% a week0.25% a week
Steady0.5% a week (suggested)0.5% a week
Faster1% a weeknot offered

For someone weighing 70 kg, Steady weight loss is about 0.35 kg a week. We turn the weekly change into daily calories using about 7,700 kcal per kilo of body weight, then take that off (or add it to) your maintenance calories. For gaining, Gentle is suggested, so more of what you gain is muscle rather than fat.

  • The cut is never more than 25% of your maintenance calories.
  • The extra for gaining is never more than 15% above maintenance.
  • When you’re losing weight, we won’t suggest fewer than 1,200 calories a day (female), 1,500 (male) or 1,350 (other), and never more than your maintenance calories.

Weight loss usually slows down over time, because your body adjusts as you get lighter. Treat the weekly rate as a rough guide, not a promise.

4. Protein

  • 1.6 g of protein per kg of body weight if you’re maintaining or gaining.
  • 1.8 g per kg if you’re losing, to help you hold on to muscle.

If your weight is above a BMI of 25 for your height, we work out protein from the weight you’d be at a BMI of 25. That keeps the number realistic. Protein never takes up more than 35% of your calories.

5. Fat and carbs

  • Fat starts at 30% of your calories. It never goes below 20% of your calories (or 0.5 g per kg), because your body needs some fat to work well.
  • Carbs fill whatever calories are left. We aim for at least 130 g, lowering fat towards its minimum first if needed.

6. Rounding

We round calories to the nearest 10, and protein, fat and carbs to the nearest gram. The app shows you the working, for example:

Calories at rest 1,710 × Fairly active 1.6 = 2,740 a day to stay the same

7. It’s a starting point, not a verdict

Every formula like this is an estimate. Real bodies differ, and yours might use a couple of hundred calories more or less than we predict. Use your target for a few weeks and watch how your weight moves, then adjust.

You can change any target, any time. If you already have numbers you like, choose “I have my own numbers” during setup and we’ll use yours.

These targets are meant for healthy adults. If you are pregnant or breastfeeding, have a medical condition, or have a history of disordered eating, talk to a doctor or registered dietitian before following a calorie target.

Sources