Our skin, bones, muscles, hair, nails and cartilage are made mainly of proteins. Proteins are also needed to make our body tick and most enzymes and hormones are made of them.
One gram of protein provides the body with 4 calories of energy, as well as amino acids – molecules that become part of us from our cells to our immune system response.
Proteins are made up of these amino acids. Of the 20 amino acids found in the human body, our body is only able to synthesise 11 of them and the remaining 9 must be obtained from our diets. Some research suggests that 10 of the 20 are essential but in any case, our bodies can not synthesise all 20 and therefore it is essential we consume these in our diets. These 9 (or 10) are known as essential amino acids.
There are 2 types of dietary proteins, complete and incomplete. Protein from animal sources is considered complete because it contains all essential amino acids. On the other hand, plant based sources typically lack one or two of these essential amino acids and therefore are considered to be incomplete. Soy and quinoa are two exceptions to this rule as they have a more balanced ratio of amino acids and are often thought of as complete proteins.
Protein digestion occurs mostly in the stomach and ends in the small intestine. When food is digested, protein breaks down into amino acids that can then be transported to the cells throughout the body to perform a variety of functions. Protein can supply the body with energy as the amino acids can be converted into glucose – however this is very labour intensive and therefore not the body’s preferred fuel source. Generally the body prefers to use the amino acids in proteins, to be used in the body and form body proteins. These are needed for the repair work in our bodies, for the production of neurotransmitters and for building new muscles and cells.
Even though most plant foods are incomplete on their own, they can give us all the essential amino acids we need if we eat a variety of them.
Some individuals choose to combine their protein sources within their meals so that they consume all essential amino acids. If you eat vegetable based proteins from different botanical sources, it can create a complete protein by filling in the ‘gaps’. For example eating seeds with lentils, lentils with brown rice, chickpeas and seeds or even hummus (as this is made from chickpeas and tahini).
It’s worth considering balance again when it comes to what we eat. If we don’t get enough protein in our diet, it can lead to decreased muscle mass and therefore decreased metabolic rate, strength loss, feelings of hunger after meals, impaired immune system and lack of the building blocks your body needs to make all the enzymes, neurotransmitters and hormones that are needed for your body to function (this can then affect your mood).
Although high protein diets are popular, too much protein may cause unhealthy levels of saturated fats in our bodies and may even stress the kidneys and liver. Excess protein will not be stored as muscle and will be stored as fat, plus it may increase your chances of dehydration.
Although many of us feel as though we don’t get enough protein, we can all easily obtain adequate protein levels from our diets whether or not we consume animal foods. There are many ‘high protein diets’ around at the moment, and as with anything it’s important to remember bio-individuality and that there is no one size fits all diet. Generally, we will be able to fill our protein requirements by having a palm sized portion of protein with every meal.
If you’re stuck on where to find protein then here are some sources:
If you’re vegan or vegetarian, you can find protein in grains, nuts, beans, soy, vegetables and seeds.
Otherwise you can find protein in animal sources such as meat, eggs, fish and dairy.
If you’re going to eat animal products then consider sourcing local, sustainable options and be mindful portion sizing –
Balance animal foods with plant foods as diets too high in animal foods are at risk of deficiencies.
To listen to the podcast episode, click on the links below: