by Rod Navajas
Ask anyone who exercises regularly and I bet they’ve all heard at some point about the importance of consuming protein to improve body composition parameters.
But the question is: Does protein consumption really matter when you are trying to improve body composition and how much you actually need?
Let’s start by talking about Macronutrients and Micronutrients.
Macronutrients are nutrients that provide us energy or calories. It includes Protein, Fat, Carbohydrate and…Alcohol.
Micronutrients on the other hand, do not provide us with energy, but are vital for the optimal functioning of the body. Micronutrients include mostly Vitamins and Minerals, but also Phytonutrients.
Protein is the macronutrient constantly linked to fitness and body composition. But why?
There are a couple of reasons why protein is frequently mentioned when we are talking about body composition.
One of the big arguments is that the protein intake recommended by government agencies are too low. A quick search on the Dietitians Australia website and you will find that the recommended daily protein intake to prevent deficiency ranges from 0.75g/kg of body weight/day for an adult women and 1g/kg of body weight/day for an older adult (over 70yo).
For example, for an adult woman weighting 60kg, the recommended intake would be 45g of protein/day.
How to measure protein intake
The most common mistake people make when measuring their protein intake is to think that the protein content in protein rich foods like meat and seafood, is equal to the actual weight of that particular food. This is actually not true.
On average, 20-25% of the raw weight of red meat, chicken and seafood is made of protein. In comparison, only 8% of tofu and 3% of cooked white rice is made of protein (1). You can see a comparison table on figure 1.
So, for the example given above, our 60kg adult woman, would need to consume 100g of lean chicken breast (22g of protein), 100g of tofu (8g), 2 eggs (12g) and 100g of cooked rice (3g), to reach the recommended amount of 45g of protein per day/day.
Remember that this is the amount necessary to avoid health complications from protein deficiency.
But what if your goal is to improve body composition?
Well, then simply avoiding protein deficiency may not be enough.
A meta-analysis and scientific review of 49 studies that included 1863 participants, concluded that the optimal amount of protein intake for a healthy adult to be 1.6g/kg of body weight/day if you want to maximize training stimulus to improve body composition (2).
In our previous example, our 60kg adult women, would then need to consume 95g of protein per day. This would equate to 200g of chicken breast (44g of protein), 200g of tofu (16g), 4 eggs (24g), 200g of cooked rice (6g) and 100g of natural yoghurt (5g).
I can safely say that most people are consuming less than 1.6g of body weight/day.
What happens when we reduce our total energy intake and consume more protein?
It appears that even a higher amount of protein per day is necessary during an energy restricted diet to improve body composition parameters.
For example, individuals who followed a 40% energy restricted diet for 4 weeks, and consumed a higher protein intake diet (2.4g of protein per kg of body weight/day), not only decreased their body fat mass more than the group that consumed a lower protein intake (1.2g of protein per kg of body weight/day), but also increased their lean mass more than the lower protein intake group (3).
Long term fat loss success is highly dependent on the ability to preserve or increase lean mass.
What happens when we increase our total energy intake and consume more protein?
A higher protein intake, also appears beneficial during an overfeeding diet (40% energy surplus) (4).
Although the increase of body fat mass across 3 groups consuming different protein intakes was similar (as expected all groups increased their body fat mass), participants who consumed 3g of protein per kg of body weight/day, not only had a lower increase of body fat mass than the group that consumed less protein (1.79g of protein per kg of body weight /day), but also had a higher increase of lean mass gain.
Interestingly, the authors also included a very low protein intake group (0.68g of protein per kg of body weight/day). Not surprisingly, this group had the worst body composition outcomes. Despite consuming 40% more calories than baseline, this group decreased their lean mass (as oppose to the other 2 groups), and had the highest increase in body fat mass than the other 2 groups.
Protein is your macronutrient ally when it comes to positive changes in body composition.
If you are someone who is looking to improve body composition, a higher protein intake than the recommended amount to avoid deficiency is necessary.
An individualised protein intake amount will be dependent on other factors such as age, training experience, training schedule and intensity and long term goals.