Protein Intake: How many grams of protein per day

[Background]

Protein is the building block of our cells, antibodies, hormones, and enzymes. Since it's so important, it'll leave us wondering how many grams of protein should we eat per day.

Yet, when we think of protein intake, the first thought is often: Muscle. 

For someone who visits the gym frequently, this is the most important macronutrient for both muscle preservation, and other fitness related goals (such as fat burning). 

However, one area that is often less discussed is how inadequate protein is detrimental not only to your fitness goals, but also to your general health. Impaired immunity, mood and cognitive abnormalities, and bone health or fracture risk are all issues that arise due to lack of protein [1, 2, 3].

This is partly due to the lack of awareness of protein importance. But if you’re reading this article, chances are you are motivated to not only look better and fitter, but also be healthier.

Here are some science based general guidelines for reference, on how much protein you should consume per day for various goals. Whether that is to get as lean/shredded as possible, gaining as large muscle as possible, or for general health benefits.

[Outline]

• Background
• Protein per Day: General Health
• Protein per Day: Gaining Muscle Mass
• Protein per Day: Burning Fat and Getting Lean (Coming Soon)
• Conclusion (Coming Soon)
• References
  

[Protein per Day: General Health]

Many individuals believe that protein is important only if you want to preserve muscle. It turns out however, that protein is just as important for the general population. The World Health Organization [4] has the following guidelines on the protein amount requirements for people of various demographics:

Table 1. Protein Requirements for men and women. Based off of World Health Organization: https://iris.who.int/bitstream/handle/10665/43411/WHO_TRS_935_eng.pdf

Meanwhile, the nutrition societies of Germany, Austria, and Switzerland (D-A-CH) has suggested higher levels for REQUIRED protein intake [5].

Table 2. Protein Requirements for men and women. Based off: https://pmc.ncbi.nlm.nih.gov/articles/PMC6492513/

That means that if you are of the age 26 years old, male, and weigh around 80 kg, you should target a daily protein intake of at least 64 g/day (80kg * 0.8g/kg) according to the D-A-CH nutrition society guidelines. 

It is important to note that these figures are the REQUIRED amount of protein. To realize the full benefits of protein, it is best to consume a higher amount assuming moderate exercise level.

For example, protein is deeply tied to mood and cognition. In a 2020 study [2], mice who have undergone protein deficiency typically exhibit behavioral abnormalities. This was fortunately reversible by adequate protein supplementation.

Protein is also linked to bone mineral density, as a 2021 study (LINK) [3] has shown that participants who consumed more than 1.1g of protein per kg of body weight had 1.8 - 6% higher bone mineral density compared to those who consumed 0.8g/kg. This 1.1g/kg figure is greater than the 0.66g/kg and 0.8g/kg figure proposed by WHO and D-A-CH’s nutrition societies. Once again, the WHO and D-A-CH numbers are the REQUIRED amounts. The optimal protein intake for further health benefits is likely to be greater than this. (Note: The 1.1g/kg and 0.8g/kg figures correlates to 15% and 13% energy from protein intake over total energy intake (TEI) respectively. The % TEI is the primary figure of comparison).

[Protein per Day: Gaining Muscle Mass]

For those who are looking to gain as much muscle mass as possible by combining high-protein intake with caloric surplus (also known as bulking), the topic of how much protein per day is highly debated in the fitness community which may be confusing at times.

However, a 2017 systematic review that stands out, which compared more than 40 studies (more than 1800 participants), with an eligibility criteria of “randomized controlled trials with RET>= 6 weeks in duration and dietary protein supplementation” [6]. They showed that protein supplementation did indeed cause greater strength and muscle size. The sweet spot? 1.62g of protein per kg of body weight per day. 

So for example, if your bodyweight is 80kg, try hitting 129.6g of protein. 

(Calculation: 80kg * 1.62g/kg = 129.6g)

It is important to remember that if the goal is to bulk, protein intake should be combined with caloric surplus. There are 2 main ways of bulking:

• “Clean” bulking: Where you put on muscle mass while avoiding fat gain. 
• “Dirty” bulking: Where you put on as much mass as possible, resulting in much higher muscle mass achieved compared to clean bulking.

Dirty bulking is when you eat as much food (including protein) as possible, regardless of whether the food is healthy or unhealthy (e.g. fries full of saturated fats). The drawback in dirty bulking (specifically excessive calories) is that while you do end up gaining more muscle mass, you also gain a significant amount of fat at the same time. This is because our body has a upper limit in the amount of muscle that can be gained per day (a mean of 0.3kg per day according to the same 2017 systematic review)[6]. Any remaining calories that haven’t been used to build muscle, will be significantly allocated to fat gain. 

For this reason, many people either follow a dirty bulk with a cut (a cut means weight loss that specifically targets fat burning and muscle preservation), or stick with clean bulking.

To clean bulk, a slight caloric surplus is necessary, typically in the range of 5% to 15% more calories than their maintenance [7]. This is so the surplus calories can be directed towards muscle gain, and minimized to prevent fat gain. Keep in mind that the authors of the same study which suggested 5-15% caloric surplus also acknowledged the possibility that increased fat gain may also increase the fat-free mass at a greater degree.

Exercise is also important to send the proper signals to your body to put on muscle mass. To understand more on how to properly train to optimize muscle gain, you may read our article on here.

[Disclaimer]

The full disclaimer can be found here: 

https://shluuup.co/pages/disclaimer

[References]

1. https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.665968/full
2. https://pmc.ncbi.nlm.nih.gov/articles/PMC7079559/
3. https://pmc.ncbi.nlm.nih.gov/articles/PMC8599066/
4. https://iris.who.int/bitstream/handle/10665/43411/WHO_TRS_935_eng.pdf
5. https://pmc.ncbi.nlm.nih.gov/articles/PMC6492513/
6. https://pubmed.ncbi.nlm.nih.gov/28698222/
7. https://pmc.ncbi.nlm.nih.gov/articles/PMC10620361/