Proteins are extremely important for good health.
It is a nutrient that must be consumed daily to meet the needs of your body.
The reference food intake (DRI) for protein is 0.36 grams per kilogram of body weight or 0.8 grams per kilogram.
However, many trials support increased protein intake for weight loss and other health benefits.
This article takes a closer look at the beneficial effects of protein and provides tips for getting the best results from a high protein diet.
What is a protein and why is it important?
Protein is one of three macronutrients, along with carbohydrates and fats.
In your body, it fulfills the following roles:
Repair and maintenance: proteins are the main component of muscles, bones, skin and hair. These tissues are continuously repaired and replaced by new proteins.
Hormones: chemical messenger proteins allow cells and organs in the body to communicate with each other.
Enzymes: Most enzymes are proteins, and the thousands of chemical reactions that occur throughout the body are caused by them.
Transport and storage: certain proteins help supply important molecules where they are needed. For example, protein hemoglobin carries oxygen to cells in your body.
Proteins are made up of smaller units called amino acids.
Of the 22 amino acids, 9 are considered “essential” in the sense that they must be consumed in food because your body cannot produce them.
Most importantly, some foods provide better protein than others based on their amino acid profile.
In general, animal products are considered “complete proteins” because they contain all of the essential amino acids in the optimal amounts your body needs. These include eggs, dairy products, meat, fish and poultry.
Plant proteins do not provide adequate amounts of each essential amino acid but can be combined with other plant sources to produce complete proteins. Beans, legumes, grains, soy, nuts and seeds are examples of plant foods high in protein.
While the quality of protein is important, the amount of protein you eat is critical.
Many researchers believe that current protein recommendations may be too low to remain truly healthy in the long term (1).
Summary: Proteins perform a number of important functions in your body. It is made up of individual amino acids, many of which your body cannot create on its own.
Effects of protein on weight loss
Research suggests that increased protein intake can have impressive effects on appetite, metabolic rate, weight and body composition.
Appetite and fullness
Eating more protein can help suppress hunger and appetite for hours after eating.
Protein increases the production of hormones such as PYY and GLP-1, which help you feel full and satisfied. In addition, it helps reduce the levels of ghrelin, also called “hunger hormone” (2, 3, 4, 5, 6).
In a controlled study of 12 healthy women, the group that ate a high-protein diet experienced higher levels of GLP-1, greater feelings of satiety and less hunger than the group that followed a diet. poor in protein (6).
Because of these effects on appetite and satiety, higher protein intake usually results in a natural reduction in food intake.
In another study, when 19 healthy young adults were allowed to eat as much as they wanted on a diet containing 30% protein, they consumed an average of 441 calories less per day than when they followed a diet consisting of 10%. % protein (7).
Interestingly, another reason why proteins are so good seems to be related to the significant increase in metabolic rate that occurs during digestion (8).
A higher protein intake can increase the number of calories burned.
Protein digestion appears to increase the metabolic rate by 20 to 35%, compared to an increase of 5 to 15% for digestion of carbohydrates or fats (9).
In fact, several studies have found that when people eat high-protein diets, they end up burning more calories for several hours after eating (8, 10, 11, 12, 13).
In a study of 10 healthy young women, a high-protein diet for one day increased the metabolic rate after meals by almost double that of a high-carbohydrate diet for a day ( 13).
Weight loss and body composition
Not surprisingly, the ability of proteins to suppress appetite, promote satiety and increase metabolism can help you lose weight.
Several high-quality studies have shown that increased protein intake promotes weight and fat loss (14, 15, 16, 17, 18).
In a six-month study of the diet of 65 overweight and obese women, the high protein group lost an average of 43% more fat than the high carbohydrate group. In addition, 35% of women in the high protein group lost at least 22 pounds (10 kg) (16).
Generally, when you reduce your calorie intake, your metabolism slows down. This is due in part to muscle loss.
However, research suggests that higher protein intake may help protect against muscle loss and maintain a high metabolic rate (15, 17, 19).
In a large review of 24 studies involving more than 1,000 people, protein-rich diets were more effective than standard protein diets in losing weight, preserving muscle mass, and preventing metabolic slowing during weight loss (15).
Above all, standard or protein diets can be effective for everyone.
But it is interesting to note that a European study concluded that on the basis of different types of genes, protein-rich diets would be particularly effective in losing weight and maintaining 67% of the population (14).
Summary: The ability of high-protein diets to reduce hunger, increase feelings of fullness, increase metabolism and protect muscles makes them effective in losing weight and improving body composition.
Other beneficial effects of proteins
In addition to its beneficial effects on weight, proteins can help improve health in many other ways:
Increase muscle mass: Studies have shown that increased protein intake can increase muscle size and strength when combined with resistance training (20, 21).
Reduce muscle loss during aging: many people lose muscle with age. One study found that adding a protein shake daily helped protect the muscle health of healthy older men and those with age-related muscle loss (22, 23, 24).
Strengthen bones: a higher protein intake can promote bone health. In one study, older women with the highest animal protein intake had a huge 69% reduced risk of hip fracture (25, 26, 27, 28).
Improved wound healing: Studies have shown that high-protein diets can improve wound healing related to surgery or injury, including pressure sores (29, 30, 31).
Summary: Research suggests that high protein intake can help build muscle, protect against bone and muscle loss during aging, and improve wound healing.
How much protein should you eat each day?
The optimal amount of protein to consume per day is somewhat controversial.
Based on the DRI of 0.36 grams of protein per pound of body weight, or 0.8 grams per kilogram, a 150 lb (68 kg) person would need approximately 54 grams per day.
While this may be enough to prevent a complete protein deficiency, many experts believe that it is too low for optimal health, including maintaining muscle mass (1, 32).
In fact, studies have shown that older people in particular need more protein than DRI, concluding that 0.6 grams of protein per pound, or 1.3 grams per kilogram, can help prevent muscle loss related to age (33, 34).
In addition, diets that provide twice the DRI at 0.75 grams of protein per pound, or 1.6 grams per kilogram, have been shown to increase weight and fat loss, improve body composition, and protect muscles during exercise. weight loss (1, 17, 18, 19, 35).
However, increasing your protein intake beyond this amount does not seem to provide any additional benefits.
A study found that men who consumed 0.75 grams of protein per pound, or 1.6 grams per kilogram, lost slightly more fat and had similar muscle gain, compared to the group who consumed 1.1 gram per pound or 2.4 grams per kilogram (18).
A high protein diet for weight loss and general health should provide about 0.6-0.75 grams of protein per pound of body weight, or 1.2-1.6 grams per kilogram and 20-30% of calories per day.
For the 150-pound (68 kg) person, this provides a wide range of about 82 to 110 grams of protein per day, depending on calorie intake.
In addition, it is important to distribute protein intake evenly throughout the day, rather than consuming most of it during a meal. This allows the body to use protein most efficiently (32).
Summary: A daily intake of 0.6-0.75 grams of protein per pound of body weight, or 1.2-1.6 grams per kilogram, can promote fat loss and protect against loss of muscle mass during weight loss and aging.
How to follow a high protein diet
A high protein diet is easy to follow and can be customized to suit your food preferences and health goals.
For example, you may want to follow a low-carbohydrate, high-protein diet to control your blood sugar.
If you avoid dairy products, you can eat a protein-free, dairy-free diet.
Even a vegetarian diet can be high in protein if it includes eggs or dairy products and many legumes and other vegetable proteins.
Here are some basic guidelines for following a high protein diet:
Keep a food journal: Start a food journal using an app or website that provides protein values for thousands of foods and lets you set your calorie and macronutrient goals.
Calculate your protein needs: to calculate your protein needs, multiply your weight in pounds by 0.6-0.75 grams or your weight in kilograms by 1.2-1.6 grams.
Eat at least 25-30 grams of protein with meals: Research has shown that consuming at least 25 grams of protein with meals can promote weight loss, muscle maintenance and better overall health (35).
Include animal and vegetable protein in your diet: eating a combination of both helps make your diet more nutritious in general.
Choose high-quality protein sources: focus on fresh meats, eggs, dairy, and other proteins, rather than processed meats like bacon and meat for lunch.
Eat balanced meals: balance protein-rich foods with vegetables, fruits and other plant foods with each meal.
Finally, this list of 20 delicious protein-rich foods can get you started.
Summary: Calculating your protein needs, monitoring your food journal intake and planning balanced meals will help you get the best results from a high protein diet.
Example of a high protein diet
The following sample provides approximately 100 grams of protein per day. However, you can adjust the portions as needed.
Breakfast: 3 eggs, 1 slice of wholegrain toast with 1 tablespoon of almond butter and a pear.
Lunch: avocado and fresh ricotta salad and an orange.
Dinner: 6 ounces (170 g) of steak, sweet potatoes and grilled zucchini.
Breakfast: smoothie prepared with 1 scoop of protein powder, 1 cup of coconut milk and strawberries.
Lunch: 4 oz (114 g) canned salmon, mixed vegetables, olive oil and vinegar and apple.
Dinner: 4 oz (114 g) grilled chicken with quinoa and Brussels sprouts.
Breakfast: rolled oats and a cup of plain Greek yogurt with 1/4 cup chopped pecans.
Lunch: 4 ounces of chicken (114 g) mixed with avocado and red pepper and a peach.
Dinner: Vegetarian chili with meat and brown rice.
Breakfast: Spanish omelet made with 3 eggs, 1 ounce of cheese, chilli, black olives and sauce and an orange.
Lunch: leftover meat with chilli and brown rice.
Dinner: 4 ounces (114 g) halibut, lentils and broccoli.
Breakfast: a cup of cottage cheese with 1/4 cup chopped nuts, diced apples and cinnamon.
Lunch: 4 ounces (114 g) canned salmon mixed with healthy mayonnaise on sprouted wheat bread and carrot sticks.
Dinner: Chicken meatballs with marinara sauce, pumpkin spaghetti and raspberries.
Breakfast: omelet prepared with 3 eggs, 1 ounce of cheese and 1/2 cup of diced potatoes.
Lunch: leftover chicken meatballs with marinara sauce and pumpkin spaghetti with an apple.
Dinner: 3 oz (85 g) shrimp fajitas with grilled onions and peppers, guacamole, 1 cup black beans on a corn tortilla.
Breakfast: protein pumpkin pancakes garnished with 1/4 cup chopped pecans.
Lunch: a cup of plain Greek yogurt mixed with 1/4 cup chopped mixed nuts and pineapple.
Dinner: 6 ounces (170 g) grilled salmon, sautéed potatoes and spinach.
Summary: Meals on a high protein diet should include a moderate to large portion of protein balanced with healthy sources of carbohydrates and fats.
Potential adverse effects of high protein diets
High protein diets are safe and healthy for most people.
Contrary to popular belief, increased protein intake does not cause kidney problems in people with normal kidney function (36, 37).
In addition, one study found that when overweight people with early-stage diabetes and kidney disease consumed a 30% protein weight loss diet for 12 months, their kidney function did not deteriorate (38). .
On the other hand, people who already have moderate to advanced kidney disease usually need to reduce their protein intake in order to maintain their remaining kidney function (39, 40).
High-protein diets can also promote kidney stones in sensitive people. One study found that this was mainly true for high amounts of animal protein rather than vegetable protein (41, 42).
In addition, people with liver disease or other serious health conditions should consult their doctor before starting a high protein diet.
Summary: High protein diets are safe and healthy for most people, but they can cause problems for people with certain illnesses or health conditions.
Protein is an important nutrient.
A higher protein intake is linked to beneficial effects on appetite, weight, body composition, aging and general health.
To get the most out of a high-protein diet, spread your protein intake throughout the day, choose high-quality sources, and balance your intake with healthy fats and carbohydrates.