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A health conscious person might wander around these days and see a lot of advertising going on, that says: "Eat More Protein!"
If you go to a site that calls itself healthline you are even presented with the title: "10 Science-Backed Reasons to Eat More Protein"
Is this really the case? For everyone? What are scientifically valid reasons that might object to such a broad and general advice?
It depends on the diet and the person. However, protein myths abound because people look at extreme ends of the scale, and assume that outlier needs are suitable for the masses.
If you are looking for homeostasis and general maintenance, then the upper limit that has been shown in studies to be beneficial is 1.6g/kg/d, or about .73g/lb/day. 1g/lb/day is a little bit of overkill, but is an easy mark to remember. Where the outlier comes in is people using steroids for bodybuilding, which allows greater protein use than in a naturally training person.
If you are looking for weight/fat loss with lean mass maintenance (i.e. losing as little muscle as possible while cutting calories), then a higher rate of protein intake is recommended to help make up for caloric deficits in carbohydrates. It is also noted that the higher the level of athlete, the less you need the protein (i.e. elite level athletes need less protein than beginners, as counterintuitive as that sounds).
From a meta analysis by Philips and Loon:
Our consensus opinion is that leucine, and possibly the other branched-chain amino acids, occupy a position of prominence in stimulating muscle protein synthesis; that protein intakes in the range of 1.3–1.8 g · kg−1 · day−1 consumed as 3–4 isonitrogenous meals will maximize muscle protein synthesis. These recommendations may also be dependent on training status: experienced athletes would require less, while more protein should be consumed during periods of high frequency/intensity training. Elevated protein consumption, as high as 1.8–2.0 g · kg−1 · day−1 depending on the caloric deficit, may be advantageous in preventing lean mass losses during periods of energy restriction to promote fat loss.
That article is an excellent read, and contains many links and references to studies on various protein intakes for low to elite level athletes and body builders.
From another very well written article:
To check if maybe there still isn't a slight benefit of going higher in protein that all these studies couldn't find, I co-authored a meta-analysis with some of the world's leading fitness researchers. We again a cut-off point at exactly 1.6g/kg/d beyond which no further benefits for muscle growth or strength development are seen.
Based on the sound research, many review papers have concluded 0.82g/lb is the upper limit at which protein intake benefits body composition (Phillips & Van Loon, 2011). This recommendation often includes a double 95% confidence level, meaning they took the highest mean intake at which benefits were still observed and then added two standard deviations to that level to make absolutely sure all possible benefits from additional protein intake are utilized. As such, this is already overdoing it and consuming 1g/lb ”˜to be safe' doesn't make any sense. 0.82g/lb is already very safe.
Examining the article you link in the question, the end includes:
Even though a higher protein intake can have health benefits for many people, it is not necessary for everyone. Most people already eat protein at around 15% of calories, which is more than enough to prevent deficiency. However, in certain cases, people can benefit from eating much more than that, or up to 25-30% of calories.
(Emphasis mine)
It then links to an article on "how much protein you should be eating", which notes:
A common recommendation for gaining muscle is 1 gram of protein per pound of body weight, or 2.2 grams of protein per kg. Numerous studies have tried to determine the optimal amount of protein for muscle gain and many of them have reached different conclusions. Some studies show that over 0.8 grams per pound has no benefit (13), while others show that intakes slightly higher than 1 gram of protein per pound is best (14). Although it's hard to give exact figures because of conflicting results in studies, 0.7-1 grams (give or take) per pound of body weight seems to be a reasonable estimate.
(Emphasis mine)
So while all the articles agree that a general intake of around 1g/lb/day is the upper limit of beneficial, they also agree that in specific diets and goals, increasing the amount of protein can aid in weight loss and lean mass retention. I believe that is the intent of your original article, despite the somewhat click bait title.
Short answer yes, unless you have got any condition stopping you from doing so.
Now the long answer:
Protein is the building block of the body. If we consider the human body as a huge network of interconnected chemical reactions, we can appreciate it a little better. Mostof chemical reactions in the body use enzymes as catalyst and most enzymes are proteins. A quick google search will provide you info on that matter.
Coming to topic at hand the protein RDA for a normal sedentary individual is 0.8-1g/kg:
https://www.health.harvard.edu/blog/how-much-protein-do-you-need-every-day-201506188096
This value pales in comparison to the protein intake of athletes and especially body builders. As you increase your physical activity your body's demand for protein increases,as you're breaking down muscle to build more: https://www.ncbi.nlm.nih.gov/pubmed/11023001?dopt=Abstract https://www.ncbi.nlm.nih.gov/pubmed/21660839?dopt=Abstract
This is the reason for the association of high intake of protein with physically active individuals.
For someone doing moderate amounts of resistance training 1.6-2g/kg should be fine. https://www.ncbi.nlm.nih.gov/pubmed/22150425
High intensity strength training individuals have been reported to take around 3g/kg.
For better explanation may I suggest this video https://www.youtube.com/watch?v=JeKn-ym6sgE
