I have always known that protein was important for bodily function, but until I actually started studying nutrition and how the digestive system works, I had no idea exactly how important it was.
Protein provides us with the raw materials that make up all of our body tissues. Our organs, muscles, nails, hair, hormones, enzymes, neurotransmitters and blood cells are all made from protein. Protein is made up of amino acids and when we eat proteins, our body breaks them down to the amino acid components which it then reassembles to form the various proteins needed for all the different body parts and functions.
The human body uses 20 amino acids (there are over 100 found in nature). They are the building blocks for proteins and there are many different combinations of these 20 amino acids that make up the various proteins needed for every aspect of our bodily functions.
Of these 20 amino acids, 9 are essential which means that they have to be obtained from food as they cannot be made at all or cannot be made in sufficient amounts to meet the body’s need. The other, non-essential amino acids can be synthesised by the body if they need to be. The essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Other amino acids may required to be obtained from food sources at various times in our lives or due to certain conditions such as phenylketonuria (PKU) where tyrosine becomes conditionally essential and must be obtained from foods.
So, obviously protein is necessary for proper functioning of our bodies and it is often associated with body builders and people who exercise a lot, but what about our brains and our mental health?
The brain and its long spidery neurons are essentially made of fat, but they communicate with each other via proteins. The hormones and enzymes that cause chemical changes and control all body processes are made of protein. Key neurotransmitters (except acetylcholine) are made from amino acids (obtained from protein). The amino acids tryptophan, tyrosine and phenylalanine are the precursors for the neurotransmitters serotonin, dopamine and norepinephrine. These neurotransmitters are involved in mood, sleep, nervous system function, anxiety, sexual function, immune function, alertness, motivation, concentration, memory, learning, appetite, blood pressure and more. Additionally, research has linked major depression with altered levels of the amino acids glutamic acid and aspartic acid as well as other amino acids such as serine, glycine. If our bodies are lacking in these amino acids then they will not be able to make adequate amounts of these important neurotransmitters and our mental health will suffer.
Almost all complete proteins come from animal sources. This means that they contain all of the essential amino acids and many of the non-essential ones too (gelatine is the only incomplete protein from animal sources as it lacks the amino acid tryptophan). Most plant sources are incomplete and therefore anyone following a vegetarian or vegan diet needs to ensure that they are careful to combine food sources so that they get all the amino acids each day. Serious physical and mental health issues can arise from a lack of essential amino acids in the body.
If the body is not supplied with adequate amino acids from food then it is forced to break down its own proteins to obtain the amino acids it needs to function. This leads to all sorts of problems including severe muscle wastage. On the other hand, the body cannot store excess protein so any amount consumed over and above the needs of our bodies will be stored as fat – yes, too much protein can make you fat. In most modern societies we consume protein in abundance so, even for people who exercise a lot, supplements and powders are rarely necessary as long as their nutrition is adequate.
So how can you ensure that you are getting enough protein in your diet to maintain physical and mental health? Make sure you include a portion of protein in every meal. Add extras such as eggs, tuna, chicken or cheese to a salad (with healthy fats from avocado, eggs, olive oil to ensure that the fat soluble vitamins can be absorbed). Combine lentils or beans with rice to get the full complement of essential amino acids and don’t consider fruit salad to be a meal! Baked treats made with coconut flour and eggs will pack a decent protein punch. There are plenty of these options here. If you are vegetarian or vegan and are struggling with physical or mental health issues then you need to ensure that you are getting enough of the right combinations of protein. Depending on the reasons for your decision to avoid meats or animal products, you might choose to consider including some more complete protein sources in your diet.
When choosing animal products try to choose grass fed and finished or free range meats, poultry and eggs as these have a higher omega – 3 to omega – 6 ratio. Animals fed on grains and factory farmed have a ratio that is too high in omega-6 fatty acids which are inflammatory and can lead to physical and mental health issues.
Photo courtesy of GiniMiniGi