chemical score - biological value

The objective measure according to the WHO reference protein

Many people choose to consume additional protein in hopes of health benefits like a strong immune system, beautiful skin, hair and nails as well as strong muscles. But more protein doesn’t automatically mean more benefits for your health.


What is protein anyway? Protein consists of amino acids, the “building blocks of life”. Protein is a collective term like carbohydrates. Carbohydrates are e.g. starch, fiber and sugar. There are enormous differences between these regarding health benefits. In the case of protein, these differences are even greater. Just because it says protein on the label, doesn’t mean something is necessarily healthy.

The biochemical composition of amino acids is what really matters when looking at protein. More specifically the amino acid building blocks the protein is made up of which  and how many of which building blocks it contains. This composition determines the chemical score. The chemical score based on the reference protein is the most objective measure of the biological value. The chemical score looks at which amino acids the proteins are biochemically made up of and how close the ratio of these amino acids is to the human need to build up the body’s own protein.

A high chemical score is always the basic requirement for a protein that the body can use well. Only then does an additional consideration of digestibility make sense. Digestibility is a factor that is practically only relevant for plant based protein when it comes to determining whether the amino acids contained are actually absorbed by the body.

Why is the chemical score based on the reference protein better than the classic biological value based on whole egg protein?

If your aim is to lay a lot of chicken eggs you should perhaps optimize your protein intake towards the amino acid ratio of the whole chicken egg and stick to the outdated “classic biological value”. Anyone whose goal is less about laying eggs and more about actually using the amino acids as a building material in their own human body is better advised to stick to the WHO reference protein, which represents the ideal ratio of amino acids. In this instance ideal means that the body can use the amino acids delivered in this ratio almost entirely to build up cells of skin, hair, nails, bones, the immune system and of course muscle cells.

How does the WHO know my amino acid needs?

The WHO reference protein is the result of countless studies in which the absorption of amino acids has been closely compared with the excretion of nitrogen waste products. The ratio that produces the least waste is the ratio that at the same time allows the body to use the most amino acids as building blocks in the body. This ratio is the WHO reference protein. The WHO reference protein is therefore not a “real protein”, but simply a specific ratio of amino acids. The ideal ratio for humans. And as humans, our amino acid needs are extremely similar. Minimal deviations, e.g. in the case of illness, sport or pregnancy, aren’t really significant. So the reference protein of the WHO is the best possible approximation for the perfect amino acid intake for all of us.

What happens to the amino acids that cannot be used as building blocks?

The amino acids that the body cannot use as a building blocks for its own protein are used to generate energy with. Depending on the amino acid, sugar is formed in an intermediate step. Wich means these amino acids are “burned” and are therefore calories. The liver detoxifies the resulting ammonia into urea, which has to be excreted through the kidneys.

I'm not interested in calories or biological value, and my kidneys are made of steel; can I now eat as much protein as I want?

High-protein products, and especially protein powders, often contain heavy metals. This applies to plant based protein powders at least as much as it does to protein powders of animal origin. Almost all manufacturers advertise that their products are laboratory tested. But this laboratory test is usually just a check for contamination. Anyone who googles “protein heavy metals” will quickly realize that exposure to heavy metals is to be taken seriously. So, regardless of the chemical score and the biological value that ensures the highest benefit from protein intake, it makes sense to focus on quality when it comes to protein. We eleven doctors from AnovonA guarantee to offer the best possible quality worldwide.