Because we are no simple bomb calorimeters.
What even is a calorie?
Fat sometimes has up to nine calories per gram, and most don’t know that sometimes it’s only four.
But if your body decides to use the fat for repairing cell walls or brain repair it becomes Zero.
Same goes for proteins. Especially if they are a from a good source (like gras fed beef) that has our optimal amino acids configuration they are often rather used for repair than for energy.
Carbs are the only exception since they’re only good for energy. And even with carbs there are exceptions like sugar alcohols or complex carbs from full grain products.
And that still doesn’t account for the subconscious influence on weight. Our body/sc can increase and decrease the level of energy you spend while not doing anything. It can slow your thoughts, reduce unnecessary movements and decrease body temperature for example to reduce the energy you spend.
Also the topic of eating healthy is extremely complex since eating disorders are heavily influenced by emotions and Traumata.
I wish it would be as simple as “just eat healthy” but for 15 years I’m stuck on a set point. I can eat what I want, I always return to my set point. If I gain weight, I’ll loose it fast until I’m at this set point. If I loose weight (through eating healthy, a diet, caloric restrictions) I’ll gain it again once my will power is depleted.
