Protein is one of the three macronutrients that is essential for the human body. Along with carbohydrates and fat, it provides energy and helps in the growth and repair of tissues.

However, unlike carbohydrates and fats, protein has other functions that make it a vital nutrient for optimal health.

The Function of Protein in the Body

Protein is commonly known for its role in muscle building. It provides the necessary building blocks, called amino acids, to generate new muscle tissue and repair existing ones.

However, besides muscle growth, protein serves many other essential functions in your body, such as building enzymes and hormones, transporting molecules, and maintaining the immune system.

Enzymes are responsible for catalyzing chemical reactions in the body. Without enzymes, we cannot process nutrients in the food we eat, produce energy, or remove waste products from our cells.

Hormones, such as insulin, adrenaline, and growth hormone, regulate various bodily functions, including metabolism, growth, and stress responses. Transport proteins, called lipoproteins, carry cholesterol and fat through the bloodstream to cells for energy and storage.

Finally, antibodies, which are made of protein, protect us from infections and diseases by recognizing and fighting off harmful pathogens.

The Recommended Daily Allowance of Protein

The amount of protein that a person needs depends on various factors, such as age, sex, weight, physical activity level, and health status.

The Recommended Daily Allowance (RDA) of protein is the minimum amount that is necessary to meet the body’s requirements. According to the National Institutes of Health, the RDA of protein for adults is 0.8 grams per kilogram of body weight per day, which is about 56 grams per day for a sedentary man and 46 grams per day for a sedentary woman.

However, people who are more physically active or have higher muscle mass might need higher amounts of protein, up to 1.6-2.2 grams per kilogram of body weight per day.

The Effects of Increased Protein Intake on Muscle Growth

One of the most well-known effects of increased protein intake is muscle growth. Consuming protein after exercise, especially resistance training, helps to stimulate muscle protein synthesis, which is the process of building new muscle tissue.

Furthermore, a study published in the Journal of the American College of Nutrition found that increasing protein intake to 1.6 grams per kilogram of body weight per day, combined with resistance training, led to greater muscle hypertrophy and strength gains than a lower protein diet (1.2 grams per kilogram of body weight per day) in young men.

However, it is important to note that consuming excessive protein does not necessarily lead to more muscle growth. The body has a limit to how much protein it can use for muscle protein synthesis.

Consuming more protein than the body needs will not result in higher gains but can put unnecessary strain on the kidneys and liver, leading to health complications.

The Effects of Increased Protein Intake on Weight Loss

Another benefit of increased protein intake is weight loss. Protein has a higher satiety effect, meaning it makes you feel fuller for longer, compared to carbohydrates or fats.

By including more protein in your diet, you can reduce your overall calorie intake and increase your metabolism, leading to weight loss.

In a study published in the American Journal of Clinical Nutrition, overweight and obese women who followed a high-protein diet (30% of total calories) for 12 weeks lost more body fat and preserved more lean muscle mass than those who followed a low-protein diet (20% of total calories). Moreover, another study published in the International Journal of Obesity found that a high-protein, low-fat diet led to greater weight loss and improvements in cardiovascular risk factors compared to a low-protein, high-fat diet.

The Effects of Increased Protein Intake on Kidney Function

There is a common misconception that high protein intake can damage the kidneys. However, this is not true for healthy individuals. The kidneys are responsible for filtering waste products from the blood.

When protein is consumed, the body breaks it down into amino acids, which can generate nitrogen waste products. However, the kidneys have no problem handling this waste in healthy individuals who consume a high protein diet.

A study published in the Journal of the International Society of Sports Nutrition found that consuming high amounts of protein (2.5-3.3 grams per kilogram of body weight per day) for 12 weeks did not harm kidney function in resistance-trained individuals.

Moreover, another study published in the Journal of Nutrition and Metabolism concluded that healthy adults with normal kidney function who consumed a high protein diet (2.2 grams per kilogram of body weight per day) for six months did not experience changes in kidney function compared to those who consumed a lower protein diet (0.8 grams per kilogram of body weight per day).

The Effects of Increased Protein Intake on Bone Health

Protein is also essential for maintaining bone health. Bones are composed of collagen, a protein that gives them their structural integrity. Moreover, bones also require calcium and other minerals to remain strong and healthy.

A diet that is high in protein, especially from animal sources, can increase the production of a hormone called insulin-like growth factor 1 (IGF-1), which is crucial for bone growth and repair.

A study published in the Journal of Bone and Mineral Research found that postmenopausal women who consumed a high-protein diet had higher bone mineral density and less bone loss compared to those who consumed a low-protein diet.

Furthermore, another study published in the American Journal of Clinical Nutrition found that a high-protein, low-acid diet increased bone mineral density and reduced bone resorption in elderly women with osteoporosis.

The Effects of Increased Protein Intake on Blood Sugar Control

Finally, protein can also help to regulate blood sugar levels. Protein is digested more slowly than carbohydrates, which means it does not cause a rapid rise in blood sugar levels followed by a crash.

By consuming more protein, you can keep your blood sugar levels stable and prevent hunger pangs and cravings.

A study published in the American Journal of Clinical Nutrition found that consuming a high-protein, low-carbohydrate diet improved blood sugar control and decreased insulin resistance in overweight and obese women compared to a low-protein, high-carbohydrate diet. Furthermore, another study published in the Journal of Nutrition found that a high-protein breakfast improved glucose and insulin responses and reduced food cravings in overweight and obese individuals.

Conclusion

In summary, protein is an essential nutrient that serves many functions in the body. Increasing protein intake can have many positive effects, such as promoting muscle growth, weight loss, kidney function, bone health, and blood sugar control.

However, it is important to consume protein in moderation and as part of a balanced diet that includes all macronutrients and micronutrients necessary for optimal health.