These calculators tend to make broad, sweeping generalizations on activity level, and fail to take into
account the nearly infinite variables introduced over the course of a full day (e.g. how far away one parks from the store, and how many cups of coffee consumed which
controls how many hours an individual spent at her desk twitching her leg, these and more can all blow
calorie calculations out the window).
Of the three factors that
account for
calorie use in an individual metabolism, digestion (which is the energy used to break down the food we consume) and physical activity we have little
control over our metabolism and our digestion.