Calories and protein for your goal

How it’s calculated

With the same math as the welcome setup in the Evzia app:

1. What you burn on a normal day: resting burn (Mifflin-St Jeor) × 1.2 plus your walking, as in the maintenance calculator.
2. The pace, a percentage of your weight per week. For losing: 0.25% (gentle), 0.5% (normal) and 0.75% (fast). For gaining: 0.1%, 0.25% and 0.5%.
3. The calories for that pace: what you burn, minus (or plus) the week’s kilos times the kcal per kilo of your body, divided by 7 days and rounded to 50. The kcal per kilo come from your body fat % (Deurenberg et al., 1991; Forbes, 2000; Hall, 2008), not the old 7,700.
4. The limits: when losing, never below 1,200 kcal or more than 25% under what you burn; when gaining, at most 500 kcal above. If a pace hits one, it shows “capped”. To maintain, what you burn.
5. Protein: 1.5 g per kilo of your weight when losing, 1.2 when maintaining and 1.8 when building muscle; with a BMI of 30 or more, 1.2. More in the protein calculator.
6. The date: the kilos you have left divided by each week’s kilos. It’s approximate: weight doesn’t change in a straight line and, once you weigh less, you also burn a little less.

To lose: calories per day = what you burn − pace × weight × kcal per kilo ÷ 7
To gain: calories per day = what you burn + pace × weight × kcal per kilo ÷ 7
To maintain: what you burn

We don’t suggest losing weight if your weight is already at the low end of healthy for your height (a BMI of 18.5 or less) or if you burn so little that eating less wouldn’t be healthy. From age 65, a healthy weight starts at a BMI of 22, so below that we don’t suggest it either: here the calculator is more cautious than the app, which looks at 18.5 at any age. And it’s a calculator for adults: before age 18, it’s best to have a doctor guide it.

A worked example

To get it right

• Start with the normal pace: it’s the one the app suggests.
• Enter the steps of a normal week, not those of your best day.
• After 3 or 4 weeks, check how your weight has changed using the average of several days. If it doesn’t move the way you expected, what you really burn is different: work it out with the maintenance calculator and your real data.
• Spread your protein across the meals of the day.
• If you want to build muscle, do strength training: without it, eating more mostly turns into fat.
• If you have diabetes or another condition, take medication that affects your weight, are pregnant or are breastfeeding, talk to your doctor first.

Frequently asked questions

How many calories should I eat to lose weight?

A bit fewer than you burn. At the normal pace, the calculator takes off what it takes to lose 0.5% of your weight a week (about 0.4 kg if you weigh 80 kg), using the kcal per kilo of your body, and it never goes below 1,200 kcal or cuts more than 25% of what you burn.

Why won’t it let me choose “Lose weight”?

Because we don’t suggest it if your weight is already at the low end of healthy for your height and age (a BMI of 18.5 or less and, from age 65, below 22) or if you burn so little that eating less wouldn’t be healthy. In that last case, what helps most to lose weight is moving more. The calculator is for adults: before age 18, it’s best to have a doctor guide it.

Which pace should I pick?

Normal is the one the app suggests. Gentle is easier to stick with, and fast asks for more effort and isn’t always possible: if it hits a limit (1,200 kcal or 25% of what you burn), it shows “capped” and stays at that limit.

Why is the date approximate?

Weight doesn’t go down or up in a straight line: water, salt or the menstrual cycle move it from one day to the next. And once you weigh less you burn a little less, so on the same calories the pace slows down. That’s why it’s worth checking how your weight is really changing every few weeks.

And for building muscle?

A little more than you burn, at most 500 kcal (the rest would mostly be fat), about 1.8 g of protein per kilo and strength training. Without training, eating more doesn’t turn into muscle.