What Happens to Body Composition by Simply Increasing Protein Intake?

When one thinks body composition change, often the first things that come to mind are resistance training and calorie restriction. But there is a third category that gets largely overlooked by the general population, OPTIMAL PROTEIN INTAKE.

These 3, work hand in hand, synergistically, at different levels and to different degrees, to aid individuals in body composition change and building the physique they so desire.

Resistance training and calorie restriction are both pretty straight forward. We know for the most part, what to expect when implementing them. As we start a resistance training program, we can expect to gain initial strength, over time we can expect to build new muscle mass, and the longer you do it the more muscle mass you build. As we begin a regiment of calorie restriction, we can expect to lose weight. And when done appropriately (paired with resistance training), we can prioritize that weight to come from fat as opposed to muscle mass.

But what happens when an individual increases their average protein intake? What would happen if one was to only increase their protein? No change in daily calorie intake, no change to daily exercise. What would happen to their muscle mass? Their body fat levels?

Luckily, we have a study in which this was looked at! The study included 47 women with normal weight obesity (meaning they had normal body weight, with above normal body fat levels), between the ages of 30 and 60. All were had a body fat percentage of 30% or more and were otherwise healthy (no chronic diseases or medications). Anyone who had seen a large amount of weight loss in the previous 3 months or that had been previously following a high protein diet were excluded from the study. Participants had to be able to maintain at least a 90% consistency with the diet or be disqualified (2 participant were disqualified).

Researchers then split the women into 2 groups, HIGH PROTEIN and STANDARD PROTEIN. That was it!! Nothing else!

So, what happened?

The researchers instructed one group of subjects to increase their daily protein intake and they instructed the other group to consume a standard protein diet for 12 weeks. The subjects were repeatedly told to not take any supplements and not to change their lifestyle during the 12-week study. At the beginning and end of the 12- week study, the researchers measured the subjects’ body composition using bioelectrical impedance analysis.

Both groups were provided with a 12-week diet that was designed to be at each subjects’ maintenance calories. The goal for this study was to make sure that the subjects were not prescribed a diet that would have resulted in weight gain (if their calories were too high) or weight loss (if their calories were too low). The researchers wanted the protein intake to be the only thing different between the two groups. The high protein group ingested 0.8 grams of protein per pound of bodyweight while the standard protein group ingested 0.5 grams/pound of bodyweight.

Again, there was NO EXERCISE DONE in this study!! The researchers were very strict about the participants not changing anything about there lives. One participant was removed because she began a workout routine.

We must keep in mind that the significance of this study was that the amount of protein taken in by each group was the only differential between the two. Any outcomes that resulted from this study can only be attributed to the different protein intakes of the participants of the study.

So, what outcome-based variables did they track? The researchers tracked changes in body weight, lean mass, body fat percentage via bioelectrical impedance analysis.

The first thing they notice when looking at the results of this study is that the subjects were able to execute the diets that the researchers prescribed. The High Protein group consumed significantly more protein during the study than the Standard Protein group. Specifically, the High Protein group increased their total protein intake from 0.5 grams per pound to 0.8 grams per pound. The Standard Protein group essentially had no change in protein intake during the study, going from 0.47 grams per pound to 0.5 grams per pound.

The High Protein group was able to hit their higher protein intake not because they added more total calories to their diet, but rather because they substituted some carbohydrates for protein. One thing that was very interesting is that the High Protein group decreased their caloric intake during the study by over 6% (from 1,956 total calories at baseline to 1,827 total calories at the end of the study).This reduction in calories did not reach the level of statistical significance, but it is interesting that by simply increasing protein intake there was a noticeable drop in the total number of daily calories taken in.

The Standard Protein group took in a daily average of 1,956 calories, 69 grams of protein, 274 grams of carbohydrates, and 62 grams of fats. The High Protein group took in a daily average of 1,827 calories, 115 grams of protein, 199 grams of carbohydrates, and 63 grams of fats.

There was a significant difference in the amount of lean mass gained between the two groups and in the amount of body fat lost between the two groups. The Standard Protein group saw a  -0.6lbs decrease of lean muscle mass, +0.4lbs of fat mass gain, and an overall +0.6% increase in body fat percentage. The High Protein group saw a +2.8lbs increase to lean muscle mass, -2lbs decrease in fat mass, and a -1.4% decrease in body fat percentage.

The Standard Protein group literally went the wrong way!! They gained body fat while losing lean mass, which is the perfect formula for increasing your body fat percentage. On the other hand, by simply increasing their protein intake the High Protein group was able to drop 2lbs of body fat and gain 2.8lbs of lean mass resulting in lowering their overall body fat percent by 1.4%!

So, how is this applicable?

I loved this study! It points out very clearly that there are some very simple steps a person new to a fitness and nutrition journey can take that can lead to some very drastic changes. This is part of why I start off with what I refer to as a “priming phase” in which we find where you as the client are in your average intake. This is a period in which we find the clients maintenance calories, or the number of calories that neither cause weight gain nor loss, so that we can have a solid baseline from which to make changes to intake as needed.

Once we have this number determined we move onto setting their macro split and daily calorie allotment. Most of the time people expect to be put on a regiment that reduces their calories. But, they are WRONG!! They are often surprised to find that we end up simply increasing their protein. Nothing else changes. I'm not naïve. I know that when I work with a client to increase their protein intakes, they will now be more conscious of all the food choices they make. This is good! Remember, they are starting this journey from a place of education (which foods have higher amounts of protein) rather than from a foundation of dieting.

My goal is to teach people to create Real Attainable Transformations and how to SUSTAIN them!

If you want to check the study out for yourself you can find it here: https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/effect-of-12-weeks-of-euenergetic-highprotein-diet-in-regulating-appetite-and-body-composition-of-women-with-normalweight-obesity-a-randomised-controlled-trial/8FB0C6CF8F3D246197100EAD55D17754