The Pros and Cons of a High Protein Diet
by Dr. Surya Bhagwati on Aug 17, 2020
Protein is one of the three main nutrients or macronutrients – carbohydrates, protein, and fats. It is therefore an essential part of any healthy diet. Protein is vital for muscle growth and repair, which is why it is so popular with athletes and body builders. The nutrient is also needed for the maintenance of the organs, bones, ligaments, and tissues. At the same time, high protein intake is associated with some risks, especially if your protein intake is higher than recommended. This can happen if your diet focuses exclusively on high protein foods or if you consume protein supplements, but don’t count them in your caloric intake. A better understanding of the benefits and risks of high protein diets can help highlight the importance of getting more protein in a safe manner.
The Pros of High Protein Diets
Better Appetite Regulation
This is one of the main reasons why high protein diets help with weight loss. Protein intake triggers an increase in levels of the hormone that causes a feeling of fullness - peptide YY. At the same time, it reduces levels of the hormone that increases the feeling of hunger – ghrelin. This results in better appetite regulation and a lower risk of food cravings. This is backed by evidence, with studies showing that an increase in protein intake (from 15 to 30% of food calories) could lead to a reduction in daily calorie intake of about 450 calories.
Muscle and Strength Gains
Amino acids in protein are the building blocks of muscles, which is why a more apt slogan than ‘no pain, no gain’ would be ‘no protein, no gain’. It is the single most important reason why bodybuilders and athletes take protein supplements. Studies demonstrate that high protein diets can promote an increase in muscle growth and mass if accompanied with weight lifting or strength training. Good protein intake can also help prevent muscle loss if you are on a low calorie diet and trying to lose weight.
Your body uses some amount of energy to digest and absorb nutrients in foods. This is described as the thermic effect of food. Foods that have a higher thermic effect will boost metabolism as they require more energy to be broken down. We know from research that protein has a higher thermic effect at about 20–35% as compared to the 5–15% for fats and carbs. Not surprisingly, study findings also point to a metabolic boost from high protein diets.
Amino acids in protein aren’t just required for muscle growth, but also for recovery and tissue repair. In fact, improved recovery and tissue repair itself promotes muscle gains and increased strength. However, this protein benefit is also important for anyone who has suffered an injury or illness as protein is needed for any tissue repair. There is plenty of evidence supporting the use of high protein foods and supplements in recovery diets for convalescing patients or in individuals who have suffered injury.
The Cons of a High Protein Diet
High protein diets can aid weight loss, but if you aren’t careful you will easily end up gaining weight. Excess protein from food is stored as body fat, while the excess amino acids are excreted. Over time this is going to add up and lead to increases in weight, rather than weight loss. This risk is higher if you consume protein shakes and supplements but do not include those calories in your daily calorie count.
A high protein diet significantly increases the risk of nutritional imbalances and deficiencies as most protein rich foods are meat based. For this reason, high protein diets can lead to a reduction in fiber and carb intake. While protein intake can be increased safely within 25% of total calories and in proportion to your bodyweight it gets harder to achieve this safely as your protein requirements increase. Inadequate fiber can cause a variety of problems, most notably increased constipation. Additionally, high protein intake increases the risk of bad breath, possibly because of ketosis.
Poor Cardiac Health
High protein diets can significantly increase the risk of heart disease, especially if most of your protein is coming from red meats and full-fat dairy. These foods are also higher in saturated fats and cholesterol, which could be the cause for this increased risk. This is also evident from studies, which show that high intake of red meat and high-fat dairy can make you more vulnerable to coronary heart disease, while the risk is lower if protein comes from poultry, fish, eggs, nuts, and vegetarian sources.
To be fair, the risk of kidney damage is not high for everyone on a high protein diet. However, it can be dangerous for anyone who suffers from kidney disease or has an undiagnosed kidney condition. This is because excess protein and byproducts like nitrogen are excreted via the kidneys. This increases stress on the kidneys, which can prove excessive if you already suffer from kidney damage. This risk is not associated with healthy adults on high protein diets, but its best to err on the side of caution and to keep protein intake within the daily recommended limits.
Like every nutrient, protein plays an important role in human health. How it impacts your health depends on how you use it. If you increase your protein intake carefully, choosing the right foods, ensuring balanced nutrition, and making sure to maintain or reduce your calorie intake, a high protein diet can help significantly.
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