How we calculate
Every rule in the app comes from published studies or official guidelines. Here you will find the rules in plain words, with the source for each one.
See how your calories are worked out
The same equation and the same factors as the app. Here you only see your maintenance calories. The weight-loss plan is built by the app, after the safety questions.
10 × 72 + 6.25 × 165 − 5 × 35 − 161 = 1,415 · × 1.5 activity
This is an estimate. In the app it is adjusted every 2 weeks from your weigh-ins. The calculation is for adults; in pregnancy and breastfeeding, needs are different. Nothing you enter here is stored or sent anywhere.
Metabolism and daily calories
Your resting metabolic rate is calculated with the Mifflin-St Jeor equation, from your sex, age, height and weight. In a 2005 systematic review it was the equation that most often came within 10% of the measured value, in people with and without obesity.
Your metabolic rate is multiplied by an activity factor from 1.35 to 1.75. If you log your workouts separately, the app counts at most half the calories shown by your watch or fitness app, so that they are not counted twice.
Adjustment every 2 weeks
The equation gives an estimate. To find how many calories your body actually uses, the app compares what you logged as eaten with the trend in your weight over the last 3–4 weeks. It needs at least 10 weigh-ins and logging on most days. It leaves out the first 1–2 weeks, because in that period weight changes mostly come from water.
At each adjustment your calories change by at most 150 a day. The app shows your weight as a 7-day average, because from one day to the next weight goes up and down by 1–2 kg with water, salt and the menstrual cycle.
How fast you lose weight
You choose a pace from 0.25% to 1% of your body weight per week. The default is 0.5%. The app never sets anyone a target above 1 kg a week. The calorie deficit stays between 15% and 25% of your maintenance calories and never goes above 750 a day.
If the date you want would need a faster pace, the app moves the date rather than cutting more calories. It shows the target date as a range of months, because nobody can predict it to the day.
Minimum calories
Your calories never go below the higher of two numbers: 80% of your resting metabolic rate, or 1,200 kcal for women and 1,500 kcal for men. The guidelines of NICE (the UK’s National Institute for Health and Care Excellence) provide for diets below 1,200 kcal only with specialist supervision.
When you reach the minimum, or after 12 weeks of dieting, the app suggests a break of 1–2 weeks at maintenance calories. When you reach your goal, you move up to maintenance calories in 1–2 steps over 2 weeks.
Protein
Protein is set per kilogram of body weight and according to how active you are: 1.2 g if you don’t exercise, 1.4–1.6 g if you play amateur sport, 1.6–2.2 g if you lift weights. It never goes below 0.83 g, the reference value for adults set by EFSA (the European Food Safety Authority), and never above 2.2 g. From the age of 65 the minimum is 1.0–1.2 g.
If your body mass index is above 30, the calculation uses the weight that corresponds to a body mass index of 30. At each main meal the target is 20–25 g of protein.
What you eat across the week
Meals follow the Greek National Dietary Guidelines for Adults: pulses at least 3 times a week, fish 2–3 times, red meat at most once, 4 portions of vegetables and 3 of fruit a day, and less than 5 g of salt. The main fat is olive oil. Fat stays at 25–35% of calories and fibre above 25 g a day.
The nutritional values of foods come from the USDA and Ciqual databases. For cooked dishes we calculate each recipe with the EuroFIR method, using factors for how much the weight changes in cooking.
The scanning traffic light
The colour of each product is set with the criteria of the UK’s official front-of-pack labelling, the same for everyone. One red is enough for the product to come out red. With no red and at most one amber, it comes out green. In every other case it comes out amber.
| Green | Amber | Red | |
|---|---|---|---|
| Fat | up to 3 | 3 – 17.5 | over 17.5 |
| Saturates | up to 1.5 | 1.5 – 5 | over 5 |
| Sugars | up to 5 | 5 – 22.5 | over 22.5 |
| Salt | up to 0.3 | 0.3 – 1.5 | over 1.5 |
For the Mediterranean diet we make a few adjustments. Olive oil and plain nuts are never worse than amber. For oily fish, an amber for fat does not count. In plain dairy products and in fruit, natural sugars count as green. Additives never change the colour. They are shown separately, with an explanation.
Safety
Before it builds a plan, the app asks safety questions, once you have given explicit consent for your health details. It does not build a weight-loss plan in these cases:
- pregnancy or breastfeeding
- age under 18
- body mass index below 18.5
- an eating disorder, now or in the past
- type 1 diabetes, or insulin and sulfonylureas without a doctor’s approval
- chronic kidney disease, stage 3 or above
- bariatric surgery in the last 2 years
- heart failure with a fluid or salt limit
In these cases it suggests healthy eating and refers you to a doctor or dietitian.
For eating disorders it uses the SCOFF questionnaire and repeats it every 3 months. If you report dizziness, fainting or your periods stopping, or if you lose more than 1.5 kg a week, the calorie deficit stops and the app advises you to speak to a doctor. For a health emergency, call 112, the European emergency number.
The AI advisors
Calories, grams and limits are calculated by the app with fixed rules, the same for everyone. Jason and Iris are AI assistants. They explain the numbers, answer questions and read photos of labels. They do not make diagnoses and do not give medicine doses.
They say that they are AI assistants, not doctors or dietitians, from the first conversation, and the chat screen states it at all times, as Article 50 of the EU Artificial Intelligence Act requires.
Who checks the rules
The Scientific Lead of MesogeaFit is Giorgos Paterakis, a dietitian-nutritionist. He has approved the app’s methods and scientific content.
If you want him to look at your plan personally, you can book an appointment with him. Appointments are in Greek only.