How protein can help you lose weight naturally
Protein is by far the most important nutrient when it comes to weight loss and a better looking body. A high protein intake boosts metabolism, reduces appetite and alters the levels of several weight-regulating hormones (1, 2, 3).
Protein can help you lose weight and belly fat and it works through a variety of different mechanisms. This article will provide you with a detailed overview of the effects of protein on weight loss.
Protein changes the levels of several weight-regulating hormones
Your weight is actively regulated by your brain and in particular by an area called the hypothalamus (4). In order for your brain to determine when and how much you eat, it processes a variety of different types of information.
Some of the most important signals for the brain are hormones whose levels change in response to food intake (5). A higher protein intake increases the levels of satiating hormones such as GLP-1, peptide YY and cholecystokinin, while reducing the levels of the hunger hormone ghrelin (6, 7, 8, 9, 10).
By replacing carbohydrates and fat with protein, you reduce the levels of hunger hormones and increase the levels of several satiating hormones. This leads to a significant reduction in hunger and is the main reason why protein helps you lose weight. It can make you automatically consume fewer calories.
Summary: Protein reduces the levels of the hunger hormone ghrelin, while increasing the levels of the appetite-reducing hormones GLP-1, peptide YY and cholecystokinin. This leads to an automatic reduction in calorie intake.
Digestion and metabolism of protein burns calories
After you eat, a few calories are used to digest and metabolize the food you just ate. This is often referred to as the thermic effect of food - TEF for short.
Although not all sources agree on the exact values, it is clear that protein has a much stronger thermic effect (20 to 30%) than carbohydrates (5 to 10%) and fat (0 to 3%) (11).
If we assume a thermic effect of 30%, this means that out of 100 kcal consumed in the form of protein, only 70 remain.
Summary: About 20 to 30% of protein calories are burned as the body digests and metabolizes the protein consumed.
Protein makes you burn more calories (i.e. it increases calorie consumption)
Due to the high thermic effect and several other factors, a high protein intake tends to stimulate the metabolism. High protein intake allows you to burn more calories around the clock, including during sleep (12, 13).
It has been shown that a high protein intake can stimulate the metabolism and increase the amount of calories burned by 80 to 100 kcal per day (14, 15, 16). This effect is particularly pronounced when calorie intake exceeds calorie consumption. In one study, an excess calorie intake in the form of protein-rich food increased the amount of calories burned per day by 260 kcal (12).
By increasing the amount of calories burned, high-protein diets could have a metabolic advantage over lower-protein diets.
Summary: A high protein intake can allow you to burn 80 to 100 kcal more per day, with one study even measuring an increase in calorie consumption of 260 kcal in the context of a calorie surplus.
Protein reduces your appetite and lets you eat fewer calories
Protein can reduce hunger and appetite via several different mechanisms (1). This can lead to an automatic reduction in calorie intake. In other words, you end up eating fewer calories without having to count calories or perform conscious portion control.
Numerous studies have shown that when people increase their protein intake, they consume fewer calories. This is true both on a meal-by-meal basis and for a sustained reduction in calorie intake from day to day as long as protein intake is kept high (17, 18).
In one study, increasing protein intake to 30% of calories consumed resulted in an automatic reduction in daily calorie intake of 441 kcal, which is a huge amount (19).
High-protein diets therefore not only have metabolic benefits, but also have "appetite benefits", which means that it is much easier to reduce calorie intake compared to a low-protein diet.
Summary: High protein diets are very satiating, which means that they lead to reduced hunger and appetite compared to lower protein diets. This makes calorie restriction during a high-protein diet much easier.
Protein reduces cravings and reduces the desire for late night snacks
Cravings are every dieter's worst enemy. They are one of the main reasons dieters fail in their diets. Another primary problem is late night snacking. Many people who are prone to weight gain get cravings in the evening and therefore eat unhealthy snacks. These calories are in addition to the calories they consume throughout the day.
Interestingly, protein can have a strong effect on both cravings and evening snacking. One study compared the effects of a high-protein diet and a diet with normal protein intake in overweight men (20) and found that a protein intake of 25% of total calories reduced cravings by 60% and halved the frequency of evening snacking!
Breakfast may be the most important meal of the day when it comes to loading up on protein. In a study conducted with female teenagers, a high-protein breakfast significantly reduced cravings throughout the day (21).
Summary: Eating more protein can lead to a significant reduction in cravings and snacking. These changes should make it much easier to stick to a healthy diet.
Protein makes you lose weight even without conscious calorie restriction
Protein works on both sides of the calorie equation. It reduces calorie intake and increases calorie expenditure. For this reason, it is not surprising to see that a high-protein diet leads to weight loss even without a conscious reduction in calorie intake, portion size, carbohydrate intake or fat intake (22, 23, 24).
In a study of 19 overweight individuals, increasing protein intake to 30% of total calorie intake resulted in a massive reduction in calorie intake (19). In this study, the subjects lost an average of 11 pounds over a 12-week period.
It is important to keep in mind that these subjects were simply adding protein to their diet and not consciously cutting back on anything.
Although the results are not always as dramatic, the majority of studies show that high-protein diets lead to significant weight loss (25). Higher protein intake is also associated with less abdominal fat - the harmful fat around the organs that can cause disease (26, 27).
Of course, weight loss is not the most important factor - maintaining the new weight and not regaining the lost fat in the long term is what really matters. Many people can lose weight on a diet, but most people gain the weight back (28).
Interestingly, a higher protein intake can also help prevent regaining the lost weight. In one study, even a small increase in protein intake (from 15% to 18% of total calorie intake) reduced weight gain after weight loss by 50% (29).
Protein can therefore not only help with weight loss, but it can also help to maintain the new, lower weight in the long term (3).
Summary: A high-protein diet can induce weight loss even without calorie counting or portion control. A small increase in protein intake can also help prevent weight gain.
Protein helps prevent muscle loss and a slowing of the metabolic rate
Weight loss is not always synonymous with fat loss. When you lose weight, muscle mass tends to decrease as well. However, what you really want is a reduction in body fat - both subcutaneous fat (under the skin) and visceral fat (surrounding the organs).
Muscle loss is a side effect of fat loss that most people don't want. Another side effect of weight loss is that your metabolic rate tends to drop. In other words, you end up burning fewer calories than you burned before losing weight. This is often referred to as "starvation mode" and can add up to several hundred fewer calories burned per day (30, 31).
Eating plenty of protein can reduce muscle loss, which should help keep your metabolic rate higher while you lose body fat (32, 33, 34, 35, 36). Strength training is another primary factor that can reduce muscle breakdown and slow metabolic rate during weight loss (37, 38, 39).
For this reason, high protein intake and heavy strength training are two surprisingly important components of an effective fat loss plan. Not only does this help keep your metabolic rate high, but it also ensures that what's underneath the fat looks good. Without protein and strength training, you could end up looking skinny fat instead of fit and lean.
Summary: Eating plenty of protein can help prevent muscle loss when you lose weight. It can help keep your metabolic rate high, especially when protein is combined with heavy weight training.
How much protein is optimal?
The official recommended daily protein intake is just 0.8 grams per kilogram of body weight. This may be enough to prevent protein deficiency, but it is far from optimal if you are trying to lose weight or build muscle.
Most studies on protein and weight loss base protein intake on a percentage of calorie intake. According to these studies, aiming for 30% of calories in the form of protein seems to be very effective for weight loss.
You can calculate this value in grams by multiplying your calorie intake by 0.075. For example, if you eat 2,000 kcal per day, then you should aim for 2,000 * 0.075 = 150 grams of protein. You can also aim for a specific amount based on your weight.
A common recommendation is 1.5 to 2.2 grams of protein per kilogram of body weight. It's best to spread your protein intake throughout the day and eat protein at every meal. Keep in mind that these numbers are not fixed - anything in the range of 25 to 35% of your total calorie intake should be effective.
Summary: To lose weight, it might be ideal to aim for 25 to 35% of your calorie intake in the form of protein.
How can you increase your protein intake?
Increasing your protein intake is easy. Simply eat more of the following protein-rich foods:
- Meat: poultry, turkey, lean beef and pork, etc.
- Fish: salmon, sardines, trout, cod, etc.
- Eggs
- Dairy products: Milk, cheese, yogurt, cottage cheese, etc.
- Pulses: kidney beans, chickpeas, lentils, etc.
If you are on a low-carb diet, you can also choose higher-fat meats. If you are not following a low-carb diet, then you should focus on lean meats. This will make it easier for you to keep your protein intake high without consuming too many calories.
Using a protein supplement can also be a good idea if you are struggling to reach your protein intake goals. Whey protein has numerous benefits, including increased weight loss (40, 41).
Although eating more protein may seem easy when you think about it, in practice it can be difficult to incorporate a higher protein intake into your life and diet plan.
It's a good idea to monitor calorie and nutrient intake, at least initially, and weigh everything you eat to make sure you're hitting your protein quota. You don't have to do this forever, but it's important in the beginning to get a good idea of what a high protein diet looks like.
Protein is the easiest and tastiest way to lose weight
When it comes to fat loss and a better looking body, protein is the king of nutrients. You don't have to sacrifice anything to benefit from a higher protein intake. It's all about adding protein to your diet.
This is especially appealing because most protein-rich foods taste good. Eating more of these foods is therefore easy and satisfying.
A high-protein diet can also be an effective strategy for preventing obesity and is not just something you can use temporarily for fat loss. By permanently increasing your protein intake, you can tip the "calories in vs. calories out" scales in your favor. Over months, years or decades, the difference in your waistline can be huge.
However, you should keep in mind that calories still count. Protein can reduce hunger and increase your metabolic rate, but you won't lose weight unless you eat fewer calories than you burn. It's definitely possible to overeat and negate the calorie deficit that comes from higher protein intake - especially if you're eating junk food. For this reason, your diet should consist mainly of whole, minimally processed foods.
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Source: https://www.healthline.com/nutrition/how-protein-can-help-you-lose-weight#section10