Did you know that 30 grams of protein from one food might not build as much muscle as 30 grams from another? It's true, and this discrepancy hinges on protein quality.
Why should you care? Well, your body needs protein for all sorts of important stuff, like building muscles, bones, and even making hormones. It's like the Swiss Army knife of nutrients.
Most people believe that 18 grams of protein from chicken is equivalent to 18 grams from lentils or peanut butter, but this isn't the case.
Not all proteins are absorbed and utilized equally. Protein quality comes down to amino acids. We don't just need protein; we need all the nine essential amino acids that that protein source provides, and they each have important functions. Just to name two, leucine is a very important amino acid for muscle growth, and tryptophan is a precursor for making the hormones melatonin and serotonin.
For example, let’s say you’re trying to build muscle, to match the leucine content, an essential amino acid for muscle growth, of 25 grams of whey protein, one would need 40 grams of soy protein or 38 grams of pea protein. Studies show that women not eating meat have less muscle mass than those who do, despite consuming the same total grams of protein.
The Digestible Indispensable Amino Acid Score (DIAAS) measures protein quality by evaluating how well proteins are digested and their amino acid content.
Animal proteins, like cow’s milk, eggs, beef, and chicken, rank higher on the DIAAS scale compared to plant protein. Plant proteins often lack one or more essential amino acids, which are crucial for muscle growth and other bodily functions. For example, lentils and peanuts are low in lysine, an essential amino acid, which can limit their effectiveness.
Soy and Pea protein powders, while good, still fall short of the quality found in animal proteins. So, DIAAS scores are considering how much and how absorbable the essential amino acids in a food are. A DIASS Score of 100+ means it’s excellent quality protein, 75+ means it’s good quality and below 75 means it’s poor quality.
These are following DIAS Scores of different proteins-
MILK/WHEY- 114
PORK-117
EGGS-113
CHICKEN- 108
SOY- 88
PEA-83
CHICKPEAS-83
RICE- 59
LENTILS(DAAL)- 54
BREAD-47
In developing countries this is even more evident. Where plant proteins dominate (such as India) the challenge is meeting the required amount of utilizable protein. Eating a variety of plant proteins can help meet amino acid requirements, but it often requires consuming more calories. Since on a per gram basis, plant-based foods just pack lesser protein content.
For instance instead of meeting your protein requirement through daal or paneer- a meal of three eggs and a steak provides a better amino acid balance and fewer calories while providing the same amount of protein. It's like choosing between a compact car and a monster truck to get to work – both will get you there, but one's going to use a lot more fuel!
If you're plant-based, don't despair! You can still meet your protein needs by cleverly combining different plant proteins— like putting together a protein puzzle – mix and match your plant proteins to get all the amino acids you need. Just remember, you might need to eat a bit more to get the same protein punch as our meaty options.
For example, in the morning if you prefer eating bread, you can add a couple of eggs. For lunch if you’re eating daal chawal, you can add a cup of yoghurt which has milk protein. (Bonus: It’s a probiotic so it also aids in digestion!)
So, what's the takeaway? Whether you're a carnivore, herbivore, or somewhere in between, understanding protein quality can help you make smart choices about your diet. It's not just about how much protein you eat, but also about the quality and variety of your protein sources.
REFERENCES- https://www.researchgate.net/figure/Difference-in-muscle-mass-index-between-omnivores-and-vegetarians-with-animal-protein_fig1_26740287#:~:text=In%20healthy%20middle%2Daged%20women,ratio%201.23)%20%5B104%5D%20.
https://radixnutrition.us/pages/defining-protein-quality