How Proteins Help In Weight Loss

We all need a dose of positive reinforcement every now and then.

That little extra push to keep us going and does not make us lose our focus.

It’s applicable to our weight loss goals. But when it comes to weight loss, motivation alone does not work. You got to see good and quick results to keep you motivated.

Out of the million, weight loss tips that we have come across, eating proteins to shed those kilos is the one that has impressed me the most.

Yep, this weight loss tip carries a lot of weight! Let’s find out how?

Why do we Need Proteins?

Protein is considered the ‘king of macronutrients’ among all the different dietary nutrients. Proteins are long chains of smaller units called amino acids.

There are 22 amino acids out of which 9 are essential amino acids- they have to be obtained from the diet as they can’t be synthesized by our body.

Proteins play a number of important roles in our body:

The most famous one: Proteins are building blocks of our body. They are essential for repair and maintenance.

They are efficient sources of energy. Small amounts of protein provide abundant energy. 1 gram of protein contains 4kcal of energy.

  • Proteins make up enzymes that carry out different biochemical processes eg: digestive enzymes break down food.
  • Hormones that regulate body function like insulin are made up of proteins.
  • Proteins also aid in the transport of biochemical molecules eg: hemoglobin transports oxygen.
  • Proteins make up structural tissues of our body like muscles and connective tissue.
  • They also form a part of the immune system as antibodies that fight infection.
  • DNA associated proteins mediate cell division and expression of genes.

Note: Proteins are extremely essential dietary components that find its use in a number of biochemical processes.

How do Proteins Affect you Weight?

Proteins affect our energy balance and weight in a variety of ways. So this is how things work.

1. It boosts your metabolism

We expend our calories in three ways: resting metabolism, diet-induced thermogenesis and physical activity.

Diet-induced thermogenesis is heat generated by processing of foods.

Every nutrient is processed differently and therefore each one of them utilises different calories.

Protein breakdown uses the highest amount of energy- 20-30% of energy content of protein is utilised in digestive degradation; glucose breakdown utilises 8% calories while fat uses only 2%.

High protein diet is proven to provide energy in the form of glucose and simultaneously it stimulates fat burning.

High protein diets have a greater thermic effect than high fat and high carbohydrate diet and it stimulates fat oxidation.

Most of these studies present that protein raises metabolism to an extent that it 80-100 calories are burned.

A study was conducted to compare the effects of high protein, low-fat diet and high carbohydrate diet on post-meal thermogenesis.

Interestingly thermogenesis was 2 folds higher in high protein diet than high carbohydrate diet and this lasted for more than 2 hours after meal intake.

Scientists concluded that this added advantage of energy expenditure linked with high protein, low-fat diet can make increase its preference among other diets for weight loss.

In a study evaluating the effect of overfeeding of proteins in humans, it was demonstrated that high protein diets stimulate energy expenditure more than low protein diets and in this study, 260 calories were expended as a result.

Now that is equivalent to the number of calories you spend while playing volleyball or doing light housework or any other moderate-intensity physical activity!

Generally, people tend to consume proteins in the evening.

But it is proven that if you evenly space out your protein intake over three meals you favour the process of protein synthesis in your body.

In fact, including proteins in breakfast can increase your metabolism and reduce subsequent calorie intake.

What does this mean? Consuming proteins can raise the metabolism and studies show an expenditure of 80-300 calories.

2. It controls your appetite and cravings

Apart from raising metabolism another reason why protein diets are preferred for weight loss is that they are effective in controlling appetite.

Leptin is the satiety hormone.

It interacts with our brain cells to reduce intake and increase the burning of calories.

Even fat cells secrete leptin, therefore the levels of leptin are proportional to the amount of fat.

However, in obese individuals, leptin levels increase to the extent that the cells become insensitive to its activity.

Results of a scientific study showed that keeping carbohydrate levels constant increasing dietary protein from 15-30% energy content can promote satiety and reduce intake by 440 calories! This is attributed to increased sensitivity of brain cells to leptin.

Ghrelin exerts the opposite action.

It is a hormone that stimulates hunger. High protein breakfasts promote weight loss, prevent fat gain and reduce appetite by suppressing ghrelin.

Protein acts on another enzyme involved in appetite regulation known as peptide YY in order to control appetite.

In fact, high protein breakfasts can reduce post-meal cravings for sweet food items. Yep, you read it right! Protein can reduce your cravings.

Food cravings may seem like a lack of self-control or discipline but in biochemical terms, it is a complex process involving the brain chemicals.

A study conducted on overweight and obese men showed that higher protein diets reduced late night food cravings and obsessive food thoughts by 60% in comparison to normal protein diets.

What does this mean? Protein interacts with satiety hormones and influences brain related chemicals in order to control appetite and cravings.

Proteins Help In Weight Loss

3. It preserves lean mass over fats during weight loss

As mentioned earlier, proteins serve as building blocks and they are responsible for the development of muscles.

Science supports the idea of high protein intake for developing muscle mass and increasing outcome of resistance training.

A healthy weight loss outcome in one in which you get rid of fat but preserve muscle mass.

A clinical trial was conducted where obese individuals were given a supplement rich in whey and leucine ( an amino acid) during a weight loss program.

Weight loss of more than 3kg was observed and muscle mass was preserved as well its strength and function improved.

High soy protein diet is proven to mediate weight loss without loss of muscle mass in obese subjects.

Many studies provide evidence that protein restricts loss of muscle mass during calorie restriction.

Dr. Donald Layman, University of Illinois suggests that a leucine-rich diet along with low carbohydrates effectively perpetuates weight loss.

Leucine directly signals muscle tissue to prevent loss of muscle during weight loss.

That is why high protein diets lead to loss of fat and not muscle whereas in high carbohydrate weight loss diet, muscle mass is lost.

Leucine interacts with insulin which helps in preserving muscle mass and also signals muscle to utilise glucose as fuel which translates as the burning of calories.

What does this mean? Protein facilitates healthy weight loss- it preserves muscle mass and burns fat.

4. It helps in maintaining weight loss over the long term

Not only does protein facilitate weight loss, it also helps in maintaining it over the long term.

A study was conducted for a period of 12 months where individuals were given a high protein or a high carbohydrate diet.

Despite of being on an equal calorie diet, the high protein group lost 53% more fat than high carbohydrate diet and overall the protein diet was found to better in terms of weight maintenance.

So if you want to lose weight and maintain it permanently, protein should be your choice.

What does this mean? High protein diets aid in weight maintenance.

Animal protein v/s Plant proteins: Which is better?

Not only does the quantity of protein matters but also quality.

There are complete proteins which have all essential amino acids and incomplete which lack a few.

Research states that complete proteins cause a greater increase in energy expenditure than incomplete proteins.

Animal proteins, meat and fish, provide all essential amino acids and since they are similar to our proteins they are used more rapidly than plant proteins. ( Read Meat Causes Weight Gain: Myth or Truth, Can Eating Fish Help In Weight Loss?)

Plant proteins lack one or two essential amino acids.

Although vegetarians need to be aware of this, that does not mean animal protein is better than vegetable protein.

It all comes with its pro and cons. A 6-ounce portion of T-bone steak provides 40g of protein and also 12g saturated fat.

Plant proteins, on the other hand, provide fibre, vitamins, and minerals in addition to proteins. However, they are low in protein content in the first place.

So to match up to animal protein, it is generally recommended that you should have a combination of plant proteins.

Vegetarians should consume tofu and other soy-based products, legumes and lentils, beans and peas, and artichokes.

Non-vegetarians should consume less of red meat as it is high in saturated fats and should opt for healthier options like seafood.

Note: There is no ‘better’ protein as such. If animal proteins provide all essential amino acids then plant proteins provide a number of other nutrients. You can eat a combination of plant proteins to get all amino acids.

Dairy Proteins: A Good source of Proteins for Vegetarians

Milk contains two types of proteins: casein (80%) and whey (20%).

Protein Digestibility-Corrected Amino Acid Score is a method of rating protein quality on the grounds of essential amino acid availability and digestibility.

This rating scale states that milk provides higher quality protein than beef, soy, and wheat.

Whey protein is a popular supplement taken by athletes and bodybuilders. It is obtained from the watery portion of milk after cheese production.

Whey protein supplementation stimulates weight loss, preserves muscle mass and increases strength.

For more details on dairy protein and weight loss click here: 7 Reasons Why Dairy Products Are Good For Weight Loss

Note: Dairy protein especially whey protein is another great source of dietary protein. Whey protein consumption preserves muscle mass during weight loss.

How Much Protein Should You Consume?

The amount of protein you consume depends on your needs whether you aim for weight loss or weight gain, your level of physical activity and your age.

WHO recommends 0.75-0.8g/kg for young as well as old individuals. Research studies recommend a range of 0.8-1.2g/kg per day for weight loss and maintenance.

Individuals who consume 1.0-1.6g/kg per of protein day are said to have a lower risk of cardiovascular diseases and they also maintain a healthy weight.

Most of the studies we reviewed suggested that energy content from protein should be 30%. So for a 2000 calorie requirement that would 600 calories.

To find out your ideal calorie requirement check out: How Many Calories Are Ideal For Weight Loss?

Note: 30% of energy content of your daily diet should be from protein.


One concern about consuming high protein diets is its effect on kidney function.

Protein breakdown leads to the production of toxic by-products like urea and uric acids.

To eliminate them the kidneys pump a lot of water to flush them out.

In this manner, high protein diets exert a diuretic effect. Now what happens is that while flushing out toxins minerals from bone are also lost leading to osteoporosis.

However many studies have proven that high protein diets do not have a detrimental effect on those who have healthy kidneys but those suffering from kidney diseases should restrict protein intake.

It is worth investigating whether high protein diets could resolve the fluid retention problem in some obese individuals.

And as far as osteoporosis is concerned most long term studies suggest that increased dietary protein improves bone health and reduces the risk of osteoporosis.


Proteins are an extremely essential class of food nutrients.

Keeping weight loss in mind, not only do proteins help us lose fat but also build and preserve muscle mass and provide a number of health benefits.

It also helps in long term weight maintenance.

Small portions of the protein are satiating and there is a great choice of protein sources making weight loss diets more flexible.

Now that is a great relief in comparison to other weight loss regimes which are difficult to adhere to. So go ahead and grab a protein-rich snack right away!




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