What is Protein?
Proteins are a type of macronutrient and the primary building blocks of the body. They are used in the building of tissues like muscles, organs and skin down to the production of smaller molecules such as hormones, enzymes and brain chemicals. In a nutshell, protein is really important for the body for more than a few reasons.
Proteins are made up of smaller building blocks called amino acids. There are 21 different types of amino acids that can be combined by the body to make a protein. So when we talk about eating protein, what we really mean is eating a combination of amino acids.
According to The School of Life Sciences, 9 out of the 21 amino acids are essential as they cannot be produced by the body. Unlike fats and carbohydrates, amino acids are not stored by the body for later use and must come from the foods that we eat. For vegans, this usually means eating a lot of plant based protein such as nuts and seeds or high protein vegetables like broccoli and spinach.
How Much Protein Do I Need?
There is common myth about protein: The more you train, the more you should eat.
However this is not necessarily the case. It is true that protein will help in the repair of muscle tissue post exercise, and that not getting enough in your diet can inhibit muscle growth. But eating too much can be counterproductive, as excess any from a high protein diet will be stored as fat. Of course, given the important roles proteins have on our body (it is essential for life to exist), not getting enough protein also has its health risks.
The British Nutrition Foundation recommends having 0.75g of protein for each kilogram of bodyweight for adults. So for an adult that weighs 80kg they would need 60g of protein per day.
For bodybuilders and athletes, the Academy of Nutrition and Diatetics recommends 1.2g to 2g per kilogram of protein per day. The important thing to note is that this higher number comes from the fact that those who are more active require a higher number of calories to maintain or increase their weight. A balanced diet is still important and as Mike Roussell puts it:
“If you're eating more than 30-35 percent of your daily calories from protein, that's too much”.
There are many articles out there that suggest having too much protein can cause health risks. However a study by the Journal of the International Society of Sports Nutrition found that strength trainers who consumed more than 4.4g of protein per kilogram (that’s more than 5.5 times the recommended amount) saw no increase in fat.
Another myth is that too much protein can lead to kidney failure. For those who have kidney disease, it is best to avoid a high protein diet. But for most people with healthy kidneys, studies have shown that there is no detrimental effect.
“Claims that a high protein diet promotes dehydration or adversely "strains" the kidney remain speculative.”
What is important is where you get your protein from, as eating animal proteins can stress the kidneys. So sticking to plant based and vegan protein sources will not increase your risk of kidney disease.
Understanding Amino Acids
Amino acids are the building blocks of protein. The human body uses just 21 of these to make all the protein it needs.
Complete protein sources contain all 9 of the essential amino acids the body requires and cannot produce on its own. The National Academy of Medicine states these foods as complete sources of protein: fish, eggs, meat, poultry, yoghurt, cheese, milk, soybean and quinoa. These are all high protein foods, but vegans limited to a handful of complete plant based protein. There are vegetables with protein that contain all essential amino acids, but these are found in small amounts.
Vegan protein sources are not just limited to a small selection of foods. Through a varied diet it is possible to have a combination of foods that do not contain all essential amino acids and still meet dietary requirements. Consuming foods with different amino acids in order to cover the 9 essential amino acids is enough for the body to use these and synthesis protein. The good news is that you can eat these foods throughout the day - you do not have to cover all of them with each meal. These plant based protein foods will be covered further down this post.
Sources of amino acids
Unless you are sticking to soybean or quinoa every day, knowing what foods to eat in order to get all of your amino acids can be a bit tricky. So I have put together a table to help give you some ideas on what to eat. Remember that you should aim to cover all the essential amino acids on a daily basis, but you don't need to cover them all with every meal.
This is a list of the 9 essential amino acids – the ones your body cannot produce and must be obtained through food.
Histidine, isoleucine, leucine, methionine, phenylalanine, threonine, tryptophan, valine and lysine.
To give an idea of what to eat, I have put this image together to show foods that have complete proteins, and ideas of food pairings that when combined provide complete sources of protein. Remember that you should aim to cover all the essential amino acids on a daily basis, but you don’t need to cover them all with every meal.