Concepts of Nutrition


macro-nutrients are needed in large amounts on a daily basis, they are the biggest proportion of dietary intake.

  • Carbohydrates are a source of energy, 1g of carbohydrates contain 4 kcal of energy. They can be separated into two groups which are simple and complex, simple carbohydrates are things like fruits and complex carbohydrates are things like wholegrain, wheat etc.
  • Proteins have a unit called amino acids, the body requires twenty amino acids but the body cannot make eight amino acids so this must be obtained from a diet on a daily basis. The essential amino acids we needs are eggs, milk, fish, meat and other dairy products. Protein mainly builds and repairs the tissue but it can be used as an energy source when there is a short supply of fat and carbohydrates.
  • Triglyceride's form the basic building blocks of fats. Each triglyceride consists of one unit of glycerol and three fatty acids. When digested, fats break down into these two components. Fats are classified as saturated or unsaturated. Saturated fats, such as butter and those found in meat, eggs and dairy. Unsaturated fats are things such as sunflower oil. 1g of fat = 9kcal. Fats also surround and protect vital organs, keep us warm and provide structural material for cells. Fats are also a source of fat soluble vitamins A, D, E and K.

Essential and Non-essential

  • Carbohydrates support health and performance and its recommended that around 50-60% of the daily calorie intake should be carbohydrates. Athletes need a bigger intake of carbohydrates as they will burn many calories off and will need an energy source. The average person will need at least 50% of their daily calorie intake to be from carbohydrates, the majority should come from starchy food.
  • Protein is required for more active people in order for them to promote growth and repair from training or competitions. The recommended protein intake should be at least 12-15% of the daily energy intake. Regular exercise will need a higher protein intake as the muscle are more in use and will need more protein to repair and grow.
  • Fats should take up at least 30-35% of the total calorie intake. Most athletes will need to reduce the fat intake as they will need a higher intake in carbohydrates for more energy.

Functions within the body:

The carbohydrates give the body energy to perform during sport. The proteins repair and build the tissue and act as a secondary energy source when there are small amounts of fat and carbohydrates. The fats provide the body with protection and warmth, they also provide the body with vitamins A,D,E,K.

  • Vitamins help the bodies immune system get stronger and prevent disease. They also facilitate to provide energy.
  • All minerals are essential for healthy development as they play key roles in enzyme and hormone production, immune system functioning, body structures and muscle contraction.

  • Fibre is a complex carbohydrate so foods like wholegrain, cereals, fruit and vegetables etc. will have fibre in them.

  • Nutritional requirements vary depending on age, sex, activity, health and other factors. For example, more calcium is required during childhood.

  • Its recommended that 50-60% of total calorie intake comes from carbohydrates. However, an athlete will require more. The majority of carbohydrate should be obtained from starchy sources. The daily protein intake should be 12%-15% of your dietary intake. Fat consumption should also be 30%-35% of your daily intake.

Common terminology

  • Recommended daily allowance, now more commonly referred to as Dietary reference values (DRV) these terms explain how much of each nutrient we should have daily.

  • Optimal level refers to the process of calculating how much of a nutrient is required based on an individual level. The individual requirements and lifestyle elements should be considered.

  • This figure represents an amount of nutrient that is thought to be high enough to meet the needs of the majority of people without causing risk to health.

  • These requirements are the most commonly used to assess daily energy requirements.

  • Self intake known as (SI) is used to indicate the intake or range of nutrients. It represents an intake that is enough for most people's body's but its not so large to cause any effects on health.

  • Estimated average requirements which is known as (EAR) are used to assess the energy requirements. Most people require more than the estimated average requirements but there are also a lot of people that require less.