Everything we do requires calories – from training in the gym to getting out of bed in a morning.
Even eating food requires some energy as we need to digest and absorbed the nutrients inside it using mechanical processes that require calories.
TEF or Thermic effect of food is the amount of kcals needed to process what we eat.
As you can see from the image, protein dominates the three in terms of how much energy is needed to digest it.
Studies by the likes of J.Antonio /S. Phillips suggest we eat anything from 1.6-2.4g per kg of body weight in protein ( depending on the individual ) to not only support recovery and muscle sustainability, but to aid body composition too.
Additionally, excess protein intake ( 2.4 g/kg upwards ) has’nt been proven to increase any fat gain, nor has it shown to be any different to lower intakes.
A lb of muscle roughly holds 600 kcals of energy, comprised 125 g of protein, some water and a little glycogen.
If we take all these figures into account when losing weight and trying to sustain muscle, low calorie and low protein diets will consequently result in muscle loss.
Balancing all dietary nutrients but prioritizing protein leads to a long term fad free, healthy, effective eating regime.