The ‘calories in vs calories out’ rule of thumb is a solid one – especially if you’re trying to lose weight and/or gain muscle.
Eat less than you expend; you lose weight.
Eat more than you expend; you gain weight.
Calories are made up of macronutrients (protein, carbohydrates and fat).
Each constituent macronutrient is digested and processed with differing levels of efficiency. It requires more energy to digest protein (20-30%) compared to carbs (5-10%) and fat (3%).
This is known as the Thermic Effect of Food (TEF).
So what does that mean?
Put in perspective based on 2000kcal of each macronutrient:
- 2000kcal Protein: 400-600kcal TEF
- 2000kcal Carbs: 100-200kcal TEF
- 2000kcal Fat: 30kcal TEF
If your consuming 2000kcal based purely on protein you’re actually storing 1400-1600kcal vs the 1970kcal using an exclusively fat-based approach.
Admittedly in the real world, nobody actually eats exclusively one macronutrient, I wouldn’t recommend it either. Eating 0kcal of protein or fat eventually leads to death, not to mention being incredibly awkward at weddings.
If you’re struggling to lose weight it’s unlikely because of excessive protein. With a high TEF and positive effect on satiety I often recommend increasing protein for the majority of my nutrition clients.
If you’re trying to lose weight it’s about stacking the deck in your favour. Higher protein diets come with significant benefits and virtually no downside.
Take home message:
Eat more protein.