High Protein Diet Weight Loss – How It Works, The Science

High Protein Diet Weight Loss – How It Works, The Science

high protein foodBy Dr Joe

Is there evidence that high protein diet weight loss actually works? As you know there are several ways to shed fat from our bodies.

One of them is the use of high protein diet. When I first started considering lightening up my body weight, I figured I could use the high protein diet weight loss method.

My plan was to replace a lot of my carbs with a lot more protein. This method of weight loss is called the low carb, high protein system.

Technically this was a feasible option and I used this option for a couple of weeks to hit my preset target weight.

I will explain later why I made this decision with this article.

What is a high protein diet?

A high protein diet is one where you consume more than the required amount of daily protein requirements. Sometimes two to three times the recommended daily allowance.

Proteins are essential for growth, wear and tear of daily living, bone development and in the case of children brain development as well in addition to the aforementioned uses.


Where do I get my proteins from on a high protein diet?

We get our proteins from 2 sources – animals and plants.

Animal sources will include cows, deer, pigs, goats, fish, birds like chicken, goose, turkey, duck etc. This will include your:

  • Milk
  • Cheeses
  • Crab
  • Prawns
  • Lamb
  • Chicken
  • Pork
  • Beef
  • Tuna
  • Cod
  • Ham and
  • Eggs

Plant sources include:

  • Legumes
  • Lentils
  • Pulses
  • Soya
  • Almonds
  • Tofu
  • Walnuts
  • Peanut

Proteins are made up of amino acids connected together in a variable amount of chain lengths to form polypeptides. Upon digestion, proteins are broken down back into their little units – amino acids. There is a concept of essential amino acids.

> Essential amino acids can’t be made by the body, so external sources are needed to provide these essential amino acids.


How much protein do I need on a high protein weight loss diet?

There are 3 ways you can calculate how high many grams of protein needed on a high protein diet.

The first method is using a simple percentage proportion. A high protein diet can be expressed as a percentage of your overall dietary intake. If you make the protein content of daily nutritional requirement above 35%, then you are within the realms of a high protein diet.

A second method of calculating how much protein you need on a high protein diet weight loss plan is to express your protein requirement per kilogram body weight or per lean body mass. It’s much simpler to calculate it on the basis of overall body weight because lean body mass calculations can be notoriously inaccurate.

Using overall body weight, a high protein diet would be along the lines of 1.2 g/kg body weight. If you weigh 100 kg, you would be eating about 120 g of protein daily (1.2 X 100 = 120 g of protein).

A third method of working out how protein you need on a high protein diet weight loss program is to use a factor of 0.08 and multiplying that by the number of calories you are eating daily. If for instance, your daily calorie intake is 1800, your high protein requirement daily would be 144 g (1800 X 0.08 = 144 g of protein)

Something else I need to mention is that consuming all of your protein needs for the day in one meal is not a good idea.

> A better plan for high protein diet weight loss plan is to spread your daily protein content over at least 3 meals. This way of eating is less stressful for your liver and your kidneys because both organs have to deal with detoxification and excretion of the by-products respectively.


If you were to have 120 g of protein for the day, you could eat 35 gm with your breakfast, another 35 gm with your lunch and the remaining 50 gm with your dinner (35 + 35 + 50 = 120 g of protein). That’s a better spread than consuming all the 120 gm in one meal.

Where do we get our essential amino acids from?

Our diet.

It is thought that animal proteins are more complete in terms of essential amino acids provision compared to plant proteins. However, plant eaters who consume quite a variety of plants needn’t worry about the completeness of their diet.

Different plants provide different amino acids.

Amino acids that plant A can’t provide, plant B would. You are covered.

I will recommend Michael Eades book below available here on Amazon.com and if you live in Europe, on Amazon.co.uk here.

high protein diet weight loss

How much protein do I need daily?

Opinions vary but research has shown that the average folk can get by with 0.6 gm/kg body weight. The average folk who is mild to moderately active could use that amount of protein and be just fine.

This also along the lines of government recommendations. Someone weighing 80 kg (176 lbs) will need only 48 g of protein daily.

Individuals who are really physically active like athletes and body builders will need between 0.8 g/kg body weight and 1.1 g/kg body weight.

The main reason being these guys have a lot of wear and tear. Therefore, their protein turn over will be higher, so they need more for repair.

How does high protein diet make you lose weight?

Several mechanisms are at play here when it comes to high protein diet weight loss. We shall talk about some of them. People always want to know if they can lose weight on a high protein diet.

Yes, you can lose weight on a high protein diet when done correctly. Indeed, weight loss is one the benefits of high protein diet. Most individuals who start a high protein diet actually do so because of the benefit of weight loss.

So, how does a high protein diet enable you to lose weight?

We explain how this happens and each of the mechanisms below can be interpreted as real benefits of a high protein diet too whichever way you look at it.

  1. High protein diets manipulate your hormonal system to your advantage

For a start your urge to eat relies on a number of factors some of which take place in the brain. The ability to feel hungry and feel full as well is actually signalled from an area in the brain namely the hypothalamus.

Hormones are the messengers here.

To feel hungry, the hormone ghrelin has to be involved in the signalling process. When ghrelin is released, hunger ensues and you get the urge to eat.

To feel full, hormones like Glucagon-like Peptide-1 and Peptide YY are released and your brain is informed that you have had enough of food. Time to call it a day.

Both hormones decrease pleasure from food, motivation to eat and indeed the frequency and quantity of food consumed.

Some production and secretion of both Glucagon-like peptide-1 and peptide YY also takes place at the level of the small intestines.

High protein meals have the ability to suppress ghrelin whilst boosting Glucagon-like Peptide-1 and Peptide YY.

> High protein diets favour the secretion of Glucagon-like peptide-1 and Peptide YY with less preference to ghrelin. This singular action has the potential benefit of making feel less hungry, less often. You eat less often which translates to fewer overall calories.


2. High protein diets are energy suckers

When you eat, the food has to be digested, has to be absorbed, has to be transported to the liver via the bloodstream, transported across the cell membrane (coating around the cell) into the cell.

The end point being final transportation into the energy-production machinery inside the cell called the mitochondria.

Now all of these activities need energy at every step of the way for them to be accomplished to keep us alive and well.

Compared to the other 2 macronutrients, (fat and carbohydrate), proteins use up a lot more energy to have all of those activities accomplished.

The point being some of the energy that your food is supposed to provide is used up just to process the food up to the point of energy release for your daily activities.

> This process of energy consumption for food processing is called thermic effect of food.


The thermic effect of protein is about 25% whilst that of carbohydrate is about 8% and the thermic effect for fat is 3%. One reason for this high thermic effect of protein is that proteins take a lot longer to digest.

As an example, if you ate a high protein meal that is supposed to provide you with about 1000 calories, you end up with about 750 calories because 250 calories will be used up for that thermic effect.

Compare that to similar 1000-calorie carbohydrate meal. This will provide you with a lot more calories – 920 calories to be precise after a thermic effect loss of just 80 calories.

So, high protein diet assists your weight loss by reducing your energy output from your high protein meal.

high protein diet weight loss

3. High Protein diet gifts you with satiety

Controlled studies have been shown to consistently prove that consumption of a high protein diet is associated with sustained levels of satiety. There have been experiments in durations ranging from 6 days to 6 months.

The mechanism seems to be as earlier described. High protein meals signal the secretion of glucagon like peptide-1 and Peptide YY. There is some potential additive effect from another hormone called cholecystokinin.

Meals between 25% and 81% protein content have been tested and have yielded improved satiety results. The overall effect is that high protein dieters looking to lose weight actually end up eating less calories from the effect of feeling satisfied for a longer time.

4. High Protein diets are cravings busters

One of the things that contribute to obesity is endless food cravings. This is a phenomenon that leads to snacking to satisfy those cravings.

You would have noticed that obese people tend to snack all day and at night before bedtime to satisfy those food cravings.

The more you snack, the more the overall calories you consume. It all adds up.

> One of the factors responsible for cravings is the dopamine activity going on in our brains. An inverse relationship has been observed between levels of food cravings and levels of dopamine activity in our brains.


This study lends credence to that view.

Researchers randomised teen age overweight girls with an average BMI of 28.6 and average age of 19, to 2 groups.

One group was given 35 g of protein in their 350-calorie breakfast alternating with 13 g protein but same 350-calorie content for 6 days. Girls in the second group were made to skip breakfast for the 6 days.

Homovanillic acid concentration is an index of the level of dopamine activity going on in our brain. The more homovanillic acid you have circulating in your blood, the less food cravings you will have.

Scientists can measure the level of homovanillic acid in our blood.

What the researchers found.

The researchers found both protein breakfast meals did reduce post-meal cravings for sweet and savory foods. There was also increased blood level of homovanillic acid in the girls having the protein breakfast meals.

Between breakfast meals, the High Proten (35 g protein) breakfast produced greater reductions in post-meal savory cravings and also elicited sustained increases in Homovanillic acid concentrations prior to lunch.

There was a positive correlation between the concentration of homovanillic acid and the protein concentration in the meal.

> With high protein dieting blunting your food cravings, you consume less calories thereby enabling weight loss.



5. High Protein diet is muscle-protective

One of the saddest things that happens to anyone trying to lose weight is that they also lose muscle. Whereas the initial intention was to lose fat, you end up losing some muscle in practice.

Why does losing muscle matter?

Losing muscle matters because muscle is one of the most metabolically active tissue in the body. The more muscle you have, the more calories you burn per unit amount of food. Your calorie output is higher with more muscles.

The converse being the less muscle you have, the fewer calories you expend. You don’t want to conserve calories when you want to lose weight. If anything, you want to burn more calories.

> Therefore, losing muscle during a weight loss plan is an unwelcome development but this muscle loss is almost inevitable. A third of the weight you lose is attributable to muscle loss.


Eating a high protein diet protects muscle. High protein diet reduces the amount of muscle loss to less than a third.

Muscle protection helps your weight loss effort and if you add resistance training to your high protein diet weight loss plan, you lose even more weight by burning lots more calories.

How much carbs can you have on a high protein diet weight loss plan?

Starting a high protein diet can be somewhat daunting at first. You are never sure how much of the other macronutrients to exclude or include in your high protein diet.

One of the first questions you will ask yourself is: how much carbs can I eat on a high protein diet?

There is no definitive one answer to that “how much carbs on a high protein diet” question. It all depends on how high you want your proteins to be. But you want your carbs to be as low as possible.

You should adopt the low carb, high protein strategy which is the more popular strategy. In this case, you want your carbs to be less than 20% of your meal arrangements for the entire day.

In real terms, the amount of carbs you need in your high protein diet weight loss plan should be less than 80 gm per day. If your protein content is very high, then the carb content should be in the region of 20 – 30 gm per day.

> Carb-Protein balance should be a see-saw effect. If you push up your protein content, the carb content should be drop correspondingly.


Most people struggle to lose weight because they are eating the wrong foods. They get what they consider to be good advice from “experts”, go along with it only to discover that they are no further forward months later. Why? Bad food advice and bad food choices but they just don’t know it.

You need to get the basics right. My friend, Mike, talks about some of those foods sabotaging your fat loss efforts. Some of the foods he talks about will surprise you. Continue to see Mike’s story here.