Methodology and sources

Calorie, macro and weight targets in LunaFY are calculated with the common scientific methods below. They are estimates based on population averages; talk to your doctor or dietitian about your personal situation.

Basal metabolic rate (BMR)

Mifflin-St Jeor equation: men = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5; women = the same formula − 161.

Source: Mifflin MD, St Jeor ST, Hill LA, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241–247. doi.org/10.1093/ajcn/51.2.241

Daily energy needs

BMR is multiplied by a factor for the activity level you choose: sedentary 1.2; lightly active 1.375; moderately active 1.55; very active 1.725; extra active 1.9. These are commonly used activity multipliers; calculating energy needs as BMR × factor follows the FAO/WHO/UNU report below.

Source: FAO/WHO/UNU. Human energy requirements: report of a joint FAO/WHO/UNU expert consultation. Rome, 2004. fao.org/4/y5686e/y5686e00.htm

Calorie target and safety floor

To lose weight, a daily deficit of 250, 500 or 750 kcal is applied depending on the diet pace you choose; to gain weight, a surplus of 60% of these values is added.

The target never goes below 1,200 kcal for women or 1,500 kcal for men. Lower targets are only safe under medical supervision.

Source: NHLBI Obesity Education Initiative. Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. NIH Publication No. 98-4083, 1998. ncbi.nlm.nih.gov/books/NBK2003

Estimated goal date

Weekly weight change is estimated by multiplying the daily deficit (or surplus) by 7 and dividing by 7,000 kcal per kilogram. LunaFY uses 7,000 kcal; the classic 7,700 kcal value (Wishnofsky) gives a slightly slower pace. Real weight change slows over time and varies from person to person (Hall et al.); the date is a rough estimate, not a promise.

Sources: Wishnofsky M. Caloric equivalents of gained or lost weight. Am J Clin Nutr. 1958;6(5):542–546. doi.org/10.1093/ajcn/6.5.542 — Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011;378(9793):826–837. doi.org/10.1016/S0140-6736(11)60812-X

Macronutrient split

The calorie target is split into protein, carbohydrate and fat as follows: weight loss 35% / 35% / 30%, maintenance 30% / 40% / 30%, weight gain 25% / 45% / 30%. Protein and carbohydrate count as 4 kcal per gram, fat as 9 kcal per gram. The protein and fat shares are within the acceptable distribution ranges (protein 10–35%, fat 20–35%). The carbohydrate share for weight loss (35%) and maintenance (40%) is below the range recommended in this report (45–65%).

Source: Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: National Academies Press; 2005. doi.org/10.17226/10490

Ideal weight and body mass index

Ideal weight is estimated with the Hamwi formula: men 48 kg + 2.7 kg for every 2.54 cm above 152.4 cm; women 45.5 kg + 2.2 kg for every 2.54 cm.

BMI = weight (kg) / height² (m). Classification uses the World Health Organization cut-offs: below 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, 30 and above obese.

Sources: Hamwi GJ. Therapy: changing dietary concepts. In: Danowski TS, ed. Diabetes Mellitus: Diagnosis and Treatment. New York: American Diabetes Association; 1964:73–78. — WHO. Obesity: preventing and managing the global epidemic. WHO Technical Report Series 894, 2000.

Water goal

Your daily water goal is 30 ml per kilogram of body weight, plus 0–800 ml depending on your activity level, rounded to 0.5 litres and capped at 4 litres. It never goes below 2.0 litres for women or 2.5 litres for men: the adequate intake of total water, including water from food, set by the European Food Safety Authority.

Source: EFSA NDA Panel. Scientific Opinion on Dietary Reference Values for water. EFSA Journal. 2010;8(3):1459. doi.org/10.2903/j.efsa.2010.1459

AI estimates

Meal photo and text analyses are estimates by Google’s Gemini AI; they are not read from a verified food database and can be wrong. Check them before saving.