Not All Proteins are Created Equal: Protein Quality
We know that intaking adequate protein is important when looking to increase lean body mass in combination with resistance training.
However, not all proteins are created equal.
We can determine the quality of a protein source by looking at it’s essential amino acid (EAA) composition, digestibility and bioavailability of the amino acids.
Next time you see an explore page graphic stating 100g of broccoli is equal to 100g of steak you can refer to the info given here/ in these studies and make your own assessment. (Hint, they are not equal. Broccoli didn’t even make this list).
This graphic ranks proteins based on a scoring system called the protein digestibility corrected amino acid score (PDCAAS) introduced by the World health organisation (FAO/WHO, 1990) and then adopted as the preferred method for measurement of protein values in human nutrition in 2000 (Schaafsma).
Study the tables from those studies, PDCAAS is the last column on the tables. Note, the values are not ranked from highest to lowest.
Typically animal protein sources are considered to be complete proteins (contain all of the EAAs) and proteins from plant sources are incomplete (generally lacking 1 or 2 EAAs). Thus, animal proteins tend to rank higher on PDCAAS.
Whey protein in particular is the highest scorer, followed by casein, cow’s milk, egg and mycoprotein.
Plant sources rank lower so a diet that’s mostly plant based could benefit from a wider variety of protein sources at meal times or the addition of supplementary EAAs if the person is looking to maximise muscle protein synthesis.
Whether you choose to eat more plant proteins than animal proteins for ethical reasons is up to you. For muscle gain or retention on a hypocaloric diet animal proteins will likely be necessary to hit daily protein targets without creating more dietary stress.
I feel choosing a variety of both plant and animal options is ideal for not only gainz but overall health outcomes in addition to some form of calorie monitoring.
Eating only animal proteins may result in higher saturated fat intake. Plant proteins come with phytochemicals and fibre that animal proteins do not.
Supplementing with whey protein seems the obvious winner for a protein supplement.
Please note: this info if for those interested in maximising muscle hypertrophy, it’s not for general fat loss.