How Does Protein Compensate for Low Carbohydrate Intake?

Because amino acids (the building blocks of protein) play such a key role in the body's functions, it tries to draw energy from sources of fuel other than protein first. However, a low-carbohydrate diet forces the body to turn to protein and fat first, which affects metabolism, muscle mass and energy levels.

Protein as a fuel source

• Protein can be used as body fuel.

  The human body can use protein housed in the liver and muscle cells for energy if it needs to. But protein requires more steps to break down than carbohydrates or fats do. When your body uses protein as its primary energy source, you might become protein-deficient and have a negative nitrogen balance (with more nitrogen excreted than used).

Protein and muscles

• Since a body on a low-carbohydrate diet may use protein as a primary fuel source, muscle tissue can decrease, reducing muscle size. If you are trying to build strength, a low-carbohydrate diet can make this more difficult .

Lack of energy

• Low-carbohydrate diets can make you feel lethargic because the body prefers carbohydrates over protein as an energy source. You may feel tired and have a "foggy" brain. However, you can learn how to eat the right amount of healthy carbohydrates to counteract this effect.

Exercise and protein

• If you are taking part in regular exercise, your daily requirement for protein may increase, especially if you are an endurance athlete or a bodybuilder. If you take in more protein from food or supplements, you may also feel better after workouts.

Protein sources

• Foods high in protein include chicken, lean red meats, beans, turkey, tofu, fish, wheat bran and eggs. Protein supplements, which often contain whey protein, are easy to take and quickly digested to replace muscle protein lost. Note, however, that some protein supplements are both high in fat calories and expensive.