Protein is important for many vital functions in your body. It provides building blocks for all of your tissues and you also need it to make hormones, enzymes and neurotransmitters (1). Another, perhaps somewhat unexpected benefit of protein is that it can play a role in weight management. How? Let’s explore the main ways in which protein may impact your body weight.
Protein makes you feel full
The first way in which protein can help you lose weight is by promoting satiety. Protein has a stronger effect on satiety than carbohydrates or fat (2). This is partly due to protein’s effect on gut hormones. After you consume protein, appetite-lowering hormones increase, while hormones that stimulate appetite decrease (3, 4). As protein helps you feel fuller – which might help you skip that tempting afternoon or late-night snack – it may reduce daily calorie intake and lead to weight loss (5-8).
Protein requires more energy for digestion and processing
When you eat food, energy is needed for digestion and processing. This is called the thermic effect of food. While as much as 20-30% of the available energy in protein is used for digestion and processing, carbohydrates require only 5-10% and fats only 0-3% of their usable energy to be used. Thus, when you eat a diet high in protein, more energy is needed for digestion and processing, which increases the amount of calories you burn (3, 4, 9).
Protein + exercise protect muscle, which burns more energy than fat
There is another way in which protein affects the rate at which you burn calories. At rest, muscle tissue burns three times more energy than body fat (10). Unfortunately, when you lose weight, you do not only lose fat, but also muscle. Here is where protein – especially together with exercise – comes to the rescue. Both exercise and high-protein diets preserve valuable muscle mass during weight loss, which helps to maintain a higher metabolic rate. When the two are combined, they have an even stronger effect on your body composition, helping you to lose fat while protecting muscle (3, 4, 11-14).
High-protein diets are effective for weight management
Indeed, many studies have shown that high-protein diets are more effective than regular diets when it comes to reducing body weight and fat loss, while preserving fat-free mass, like your muscles. An additional bonus is that diets that are high in protein may also prevent weight regain after weight loss (3, 9, 11, 15-21).
So, protein is not only vital for your bodily functions, but it can also play a major role in your weight management plan. Protein can make you feel full, increase the number of calories you burn and spare your muscles. This is what makes high-protein diets so effective for losing weight (keeping it off) and improving body composition.
References
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10. Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids: Food and Nutrition Board; 2005.
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