Every target and grade in MacroTracker is worked out from published nutrition guidance. This page is which guidance, what the app does with it, and where to read the original. The same information is in the app under Settings → About → Sources, and from every screen that shows a derived number.
MacroTracker is not a medical device and gives no medical advice. Talk to a doctor or a dietitian before changing what you eat, and especially if you are pregnant, breastfeeding, under 18, an athlete in training, or living with diabetes, kidney disease, an eating disorder, or any condition that affects diet.
The calories your body uses at complete rest, estimated from your height, weight, age and sex with the Mifflin-St Jeor equation.
The equation was published with a term for male and female only. The midpoint used for "prefer not to say" is this app's own choice, not part of the published equation, and it is an approximation rather than a result for anyone.
Source. Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition, 1990; 51(2):241–247. pubmed.ncbi.nlm.nih.gov/2305711
Resting energy multiplied by an activity factor, which estimates everything you burn on top of rest across a normal day.
These are the activity factors in common use for this kind of estimate. FAO/WHO/UNU put habitual lifestyles in a narrower band, from 1.40 for sedentary living up to 2.40 for vigorous work, so the low end here sits below their published range. Either way an activity factor is a category, not a measurement of you.
Source. FAO, WHO and UNU. Human energy requirements: report of a joint FAO/WHO/UNU expert consultation. 2004. Chapter 5 defines physical activity level as total energy expenditure divided by resting energy, and gives the lifestyle ranges above. fao.org/4/y5686e/y5686e07.htm
Maintenance calories adjusted for the goal you chose, then held above a floor so an aggressive deficit on a small body cannot produce a target that is unsafe to eat to.
The percentages are this app's own presets, not a published prescription. The 1,200 kcal floor is the lower bound of the range the guideline below recommends for women; that guideline puts the floor for men higher, at 1,500 kcal. A target below roughly 1,500 kcal is worth raising with a doctor or dietitian rather than adopting from an app.
Source. American Heart Association, American College of Cardiology and The Obesity Society. 2013 AHA/ACC/TOS Guideline for the Management of Overweight and Obesity in Adults. Where calories are restricted for weight loss, it recommends prescribing 1,200–1,500 kcal/day for women and 1,500–1,800 kcal/day for men rather than going lower. pmc.ncbi.nlm.nih.gov/articles/PMC5819889
Your calorie target divided across protein, carbohydrate and fat by the split you chose, then converted to grams using the Atwater factors.
The Acceptable Macronutrient Distribution Ranges for adults are 10–35% protein, 45–65% carbohydrate and 20–35% fat. All three presets here sit below that range for carbohydrate, High protein sits above it for protein, and Lower carb sits above it for fat. They are common athletic and weight-loss splits rather than the reference ranges, and Settings → Goals will take your own numbers instead.
Sources. Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. National Academies Press, 2005. nap.nationalacademies.org/catalog/10490
FAO. Food energy — methods of analysis and conversion factors. FAO Food and Nutrition Paper 77, 2003, section 3.5.1, for the Atwater general factors. fao.org/4/y5022e/y5022e04.htm
A meal is scored on sugar, saturated fat and sodium against a third of the daily intake recommended for an adult, and the worst of the three sets the letter — the rule Singapore's Nutri-Grade uses for drinks.
Nutri-Grade is a beverage label scored per 100 ml on sugar and saturated fat. Applying it to a plate of food, adding sodium, and dividing the day by three main meals are all this app's own extensions, not part of the scheme. The daily figures themselves come from the guidelines below, on a 2,000 kcal diet — if you eat materially more or less than that, your own share differs.
Sources. Health Promotion Board, Singapore. Measures for Nutri-Grade. hpb.gov.sg/healthy-living/food-beverage/nutri-grade
Health Promotion Board, Singapore. Dietary guidelines for adults, on HealthHub: under 5 g of salt (2,000 mg sodium) a day, under 10% of energy from saturated fat, and no more than 10% of energy from sugar. healthhub.sg
World Health Organization. Guideline: sugars intake for adults and children. 2015. Free sugars below 10% of total energy, about 50 g a day on a 2,000 kcal diet. who.int/publications/i/item/9789241549028
World Health Organization. Saturated fatty acid and trans-fatty acid intake for adults and children: WHO guideline. 2023. Saturated fat at or below 10% of total energy, about 20 g a day on a 2,000 kcal diet. who.int/publications/i/item/9789240073630
World Health Organization. Guideline: sodium intake for adults and children. 2012. Less than 2,000 mg of sodium a day for adults. who.int/publications/i/item/9789241504836
The calories and macros on a logged meal are a model's estimate from a photograph or a description, not a measurement. A photo cannot show the oil in the pan or what is under the sauce, and portion size is the hardest part of the guess. Treat them as a trend over weeks, not a figure for any clinical purpose.
Questions, or a correction to anything on this page: xtde8in7o@relay.firefox.com. The support page covers everything else.