Any diet that places you in a deficit can result in weight loss, so you could simply limit calories in general and lose weight.
However, there are a number of reasons why restricting carbohydrate calories especially can aid in achieving advanced fat-loss goals.
If you dive headfirst into a low-carb diet without understanding why and how it works, you're likely to slip into a rabbit hole of carbophobia and unnecessary food avoidance.
A distinguishing characteristic of physique athletes is that they are not afraid of carbohydrates; they learn to manipulate them by eating more at certain times and less at others.
The following are some of the reasons they (and you) may wish to lower them:
1. Low-carbohydrate, high-protein diets are extremely caloric.
Protein, at up to 30%, has the largest thermic effect of any food.
For instance, if you consume 100 calories of chicken breast, 30 of those calories are expended in digestion and utilization. The net calorie count is only 70.
Ironically, it is the high protein content that confers the metabolic advantage, not the low carbohydrate content, and so it may be more correct to state that high-protein, low-carb diets aid in fat loss rather than crediting the low carbohydrate content alone.
Protein is less likely to be turned to fat than any other macronutrient due to its high thermic impact.
2. Low-carbohydrate diets assist in calorie control, hunger reduction, and increased satiety.
Protein is the most satiating macronutrient available.
Dietary fat enhances the flavor of food, which has a subjectively pleasing impact, but does not physiologically fulfill hunger in the same manner that protein does. Protein makes you feel fuller and hormonally suppresses hunger.
Protein-rich meals boost levels of glucagon-like peptide (GLP-1), a hormone that makes you feel full, and PYY, a hormone that suppresses hunger.
3. Low-carbohydrate diets aid in insulin control.
When carbohydrate intake is reduced, insulin production is decreased. Because elevated insulin levels hinder the release of stored fat, lowering insulin levels through carb restriction may aid in fat reduction, particularly the final few pounds of resistant fat.
Certain forms of stubborn fat deposits are extremely sensitive to insulin's actions and less receptive to the release of stored fatty acids.
When insulin levels are low, it is easier for stubborn fat to be released into circulation and subsequently burned for energy.
4. Low-carbohydrate, high-protein diets aid in the reduction of water retention.
A high-protein, low-carbohydrate diet has been shown to reduce water retention.
This gives your muscles a more defined appearance. Bloating and puffiness associated with water retention are transient and should not be confused with true changes in body composition.
However, increased muscle definition is another reason why physique athletes prefer this type of diet during their last peaking phase.
