Encourage HBV (High Biological Value Protein) protein with each meal.
Most animal sources are complete proteins, and some plant proteins are as well. By combining several types of plant proteins (beans and rice for example), even non-meat eaters get complete protein.
The biological value of a protein:
Let’s dive a bit deeper now. When a protein contains the essential amino acids in a proportion similar to that required by the body, it has a high Biological Value. When one or more of the essential amino acids are missing or present in low numbers, the protein is has a low biological value.
The biological value of a protein is a number from 100 down to 0, that describes how well it is absorbed by the body. More precisely, it is a measure of the percentage of the protein that is actually incorporated into the proteins of the human body.
The table of biological values shows that the proteins in eggs (white AND yolk) have the highest biological value. Rice (brown) and quinoa have higher biological value than beef or chicken! Of course, this is per gram of protein consumed. Beef and chicken are much denser in protein per serving than rice is.
Why is biological value so important?
Unlike carbs or fats that can be stored in the body for future use, unused amino acids (protein) are excreted. Consuming a lot of food with a protein that has low biological value will not be very effective because most of the protein will not be utilized.
The biological value is determined by the amino acid composition of the protein and can only be as high as the amount of limiting amino acid present – the amino acid present in the smallest amount in the protein. In many cases, the limiting amino acid is lysine, which is not as common as the other amino acids.
The limiting amino acid tends to be different in different proteins, so when two plant based protein sources are eaten at a meal, say a grain (rice) and a pulse (lentils), the amino acids of one protein may compensate for the limitations of the other, resulting in a combination of higher biological value.
Other factors influencing Biological Value:
Methods of food preparation also have an impact on the biological value of protein in a food source; they may damage some of the essential amino acids.
High protein diets automatically reduce the biological value of all proteins consumed, because the body is getting more amino acids than it can actually metabolize at any given time.
The table of biological values provides information for an individual food consumed in a sterile lab situation. Everyday consumption is very different – with a combination of protein sources being eaten at the same time. The result is normally a higher biological value.