We know that we need protein but what is it? Well, for starters Protein (or sometimes referred to as ’proteins’ with an ’S’) is a macronutrient. It is one of the four macronutrients that provide us with energy (the other three macronutrients are carbohydrates, fat and alcohol).
The protein in your food is actually made up of something called ’amino acids’. Most people refer to amino acids as the ’building blocks’ of proteins. Several thousand amino acids linked together in chains form a protein. Every protein in your body and in your food is formed from the bonding of various amino acids into different configurations.
There are 22 amino acids in total. Out of the 22 amino acids, nine are considered ’essential’ meaning you must consume them in your diets since your body cannot make them out of other material. The other 13 are considered non-essential, meaning your body can make them through various metabolic pathways.
While all 22 are required by our bodies to function properly, it is the 9 essential amino acids that we need to get from our diet that make it important that we eat protein on a somewhat regular basis.
The common view in most fitness magazines is that the main role of protein in the body is to aid in the recovery and growth of the muscles after a workout. However this view is extremely short sited. It is true that as a major constituent of the diet, protein serves as the foundations for health, repair and replenishment, but not just for muscles.
Our skin, hair and connective tissue are all made up of protein. As are important chemical messengers such as enzymes, neurotransmitters and hormones. In fact, protein is vital for practically every process that occurs within the body such as metabolism, digestion and the transportation of nutrients and oxygen in the blood. It is this role that makes protein an essential part of your diet
We can get protein from both animal and vegetable sources (and to a much lesser degree fruits and nuts). In general animal protein and vegetable protein probably have the same effects on our health (however other compounds within the foods such as the fatty acids or phytosterols may have very different health effects).
Some of the protein you eat contains all the essential amino acids, and is thus called a complete protein. Most animal sources of protein tend to be complete.
If a protein source lacks one or more ’essential’ amino acids then they are called incomplete proteins, these usually come from fruits, vegetables, grains, and nuts.
Vegetarians need to be aware of this fact since they do run a small risk of creating a nutrient deficiency if they do not ensure they eat a variety of protein from different vegetable sources. People who don’t eat meat, fish, poultry, eggs, or dairy products should eat a variety of protein-containing foods each day. They don’t have to ’protein combine’ at every meal, but they should make a point of consuming protein from a variety of sources.
Interestingly, the same could be said for non-vegetarians as well, increasing the variety of protein sources you consume is probably a good idea in general.
Protein is also available in supplement form. It can come in powders, bars and gels or, as amino acid supplements. While the protein in supplements is typically the same as found in foods (In terms of nutritive value) it can act differently in the human body.
Highly processed proteins such as whey protein or casein tend to enter the body very quickly (this is true even of the so-called slow release micellar casein protein powders). This rapid rate of entry can cause a more pronounced insulin spike compared to the proteins from foods (Yes, protein can spike Insulin). In the vast majority of people this effect is inconsequential, however it may be important for those people who are highly sensitive (such as those on various medications) as they could suffer from something called leucine-induced hypoglycemia.
There is also a small risk of creating amino acid imbalances by consuming large quantities of single amino acids, however this is rare and does not seem to occur with the more popular amino acids supplements such as Branched Chain Amino Acids.
In general, protein supplements are just that - a quick and convenient way to supplement daily protein. With that said, reaching average protein requirements should almost always be possible with food based proteins alone.
In summary proteins are large chemicals found in our foods that supply us with calories (roughly 4 Calories per gram, but it varies depending on the amino acid make up of the protein). Protein also supplies building blocks for our bodies (amino acids), and act as messengers for many metabolic reactions (leucine ’turns on’ protein synthesis in fat and muscle cells).
Protein is a necessary component of your diet and getting your protein from a variety of sources is a good rule of thumb to follow no matter what style of diet you have. Vegetarians and especially vegans will need to pay a bit more attention to how they mix and match foods on a daily and weekly basis to ensure they get all of the essential amino acids required for optimal intake and health.
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