Protein is essential for growth and other functions, but can we have too much of it? Is there a minimum amount we should have daily? This post will look at all the basic facts about protein.
What Is a Protein Exactly?
To understand the controversy, which swirls around proteins, we first need to know how proteins are formed.
Proteins are made up of amino acids. Amino acids are the building blocks of life, promoting growth and regulating almost every biochemical reaction in the body.
The human body uses 20 amino acids in various combinations to form proteins. While the body can make 11 of them, the other nine—or the so-called essential amino acids—must come from our diet.
The essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
All plant foods provide the nine essential amino acids, but their relative concentrations vary in comparison to animal foods. And this distinction makes all the difference!
Why More Protein Is Not Necessarily Better
While we can all agree that protein is an essential building block for our muscles and cells, the exact amount of protein we need is the subject of hot debate.
One thing for sure is that historically we have struggled to get the number right.
But over time, we have realized that less is better.
This protein ‘craze’ began over 100 years ago and reached its peak in the 1950s when the United Nations declared protein deficiency a serious threat to health worldwide. Around that time, high protein diets started to emerge, and average weight people were encouraged to eat as much as 100 grams per day.
As it turns out, however, there was little evidence of a dietary protein deficiency, and by the 1970s a massive recalculation of human protein requirements was undertaken. Today, as we talked about in our article Protein—Too Much of a Good Thing? the recommended amount is ~54 grams per day (for a 150 lb. person), half of the level suggested in the 50s.
Furthermore, we have discovered that too much protein (versus too little) can pose a serious health risk. The adverse effects associated with long-term high (animal) protein diets include bone and calcium imbalance kidney dysfunction, liver problems, increased cancer risk, and worsening of coronary artery disease.