The word protein comes from the Greek word proteos, meaning primary. This indicates its importance. Protein is a vital nutrient that has many critical roles in the body. Proteins are made up of units called amino acids. There are 22 different amino acids used in the human body. Nine of these have to come from the food we eat and are called essential. The body can make the others though they may also be found in food. Amino acids are joined together to make the many different types of protein found in the body.
Here are just some of the many functions of protein:
Structure, Repair and Maintenance
Protein is vital for building, maintaining and repairing body tissue. Hair, skin, eyes, muscles and organs are all made from protein. Children need more protein per pound of body weight than adults because they are growing new tissues made from protein.
Protein is a source of energy. If you consume more protein than you need for body maintenance and other necessary functions, it can be used for energy. If it is not needed for energy it will be converted to fat and stored on the body.
hormones are protein based. Hormones help control many body functions. For example, insulin is a protein based hormone that regulates blood sugar.
Enzymes are proteins that increase the rate of chemical reactions in the body. For example, digestive enzymes are involved in the digestion of protein, carbohydrate and fat.
Transportation and Storage of Molecules
Transport proteins bind and carry molecules within cells and throughout the body. For example, haemoglobin is a protein that transports oxygen in the blood. Protein is also used to store certain molecules such as the protein ferritin, which combines with iron for storage in the liver.
Protein forms antibodies which identify and help to destroy antigens such as bacteria and viruses. For example Immunoglobulin G (IgG).
Protein in Food
All whole foods contain differing combinations of amino acids. In general, animal proteins like meat, dairy, and eggs contain all the essential amino acids and are called complete protein. Soya beans are one of the few plant foods that are considered to be a complete protein. Other plant foods such as beans, grains and nuts are rich in some amino acids but may be low in others. Combining a range of protein containing plant foods usually ensures a balanced intake of amino acids.
How Much Protein Do We Need?
According to the British Nutrition Foundation it is recommended that adults eat 0.75g of protein per kg of body weight per day. However, needs vary depending on body size and activity level. Endurance exercise and strength training may increase protein needs. Protein requirements also increase during periods of growth such as childhood, pregnancy and lactation, and when recovering from injury or surgery.
Between 10 and 35 percent of calories should come from protein each day.
Too Much or Too Little
Protein deficiency is rare in developed countries. Those at risk include people on diets who don’t, or can’t, eat a wide range of foods, people with eating disorders, or those who can’t cook, for example, due to lack of time, when travelling, in older age or due to inadequate cooking facilities.
Chronic Protein deficiency may lead to:
- poor growth and repair of body tissues
- loss of muscle mass
- reduced immunity
- weakening of the heart
- respiratory problems
Excess protein intake may increase the risk of:
- liver or kidney problems
- weight gain
- calcium loss in the urine
Consuming more than 2.5 g of protein per kg of body weight may be dangerous to health.
Dietary Sources of Protein
Eggs, meat, fish, poultry, nuts, seeds, tofu, tempeh, beans, peas, lentils, quinoa, sea vegetables, green vegetables.
Extra Sources of Protein
For those with higher protein requirements or who need an easy source of protein on the go:
Designed to aid those with extra requirements for protein without wanting to take in the extra fat or carbohydrates that usually comes with it. It is a high protein, low fat, low carbohydrate blend enhanced with metabolism-boosting compounds such as green tea and L-Carnitine. It can be taken after training to replenish and repair muscles or as a meal replacement at any time of day. Whey protein is easily utilised by the body due to its amino acids profile.
A good option for vegans, vegetarians or anyone needing a tasty snack. They are high in plant based protein, low in sugar, low in calories and great tasting. They can be used to support weight loss regimes, as post exercise snacks, or to take on journeys.
A delicious source of nutritious protein that may aid blood sugar control. Eating a low carbohydrate diet that replaces some staple foods with nuts, such as peanuts or almonds, has been shown to reduce weight, improve blood glucose, and regulate blood lipids in patients with type 2 diabetes. Tom Oliver Peanut butter is a perfect snack for spreading on bread or crackers or eating straight from the jar!