BMR
BMR, basal metabolic rate, is the estimated energy a body uses at complete rest over a day, before any movement or digestion is counted. IZeat stores no BMR and uses no formula for it; the customer's calorie target is the only reference a day is compared to, and it is set by the customer, not derived.
Several published equations estimate BMR from age, sex, height and weight, and they disagree with each other and with measurement by a margin that matters for a daily target. IZeat's rule is that any formula it used would have to be named and sourced, and it uses none: the product records and compares, it does not model a body. The assistant may discuss BMR with the customer as their general assistant; nothing of that is written into IZeat unless the customer sets a target.
Most calorie calculators start from a BMR equation and multiply by an activity factor, which is why two calculators can disagree by several hundred calories for the same person. IZeat does not add a third opinion. If a customer wants the arithmetic, their assistant has it; if they want to know what they actually ate, IZeat has that, and it is the half of the picture no calculator can supply.
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