Human Nutrition

• • A balanced diet consists of all of the food groups in the correct proportions
  • The necessary food groups are:
  • Carbohydrates
  • Proteins
  • Lipids
  • Vitamins
  • Minerals
  • Dietary Fibre
  • Water
• Carbohydrates are a source of energy
• Proteins are a used for growth and repair
• Lipids are used for insulation and energy storage
• Dietary Fibre provides bulk (roughage) for the intestine to push food through it
• Vitamins are needed in small quantities to maintain health
• Minerals are needed in small quantities to maintain health
• Water is needed for chemical reactions to take place in cells
• Vitamin C forms an essential part of collagen protein, which makes up skin, hair, gums and bones.

  Vitamin C deficiency causes scurvy
• Vitamin D helps the body to absorb calcium and so required for strong bones and teeth
• Calcium is needed for strong teeth and bones and involved in the clothing of blood

  Deficiency can lead to osteoporosis later in life
• Iron is needed to make hemoglobin, the pigment in red blood cells that transports oxygen
• The amount of energy young people need increases towards adulthood as this energy is needed for growth. Children need a higher proportion of protein in their diet than adults as this is required for growth. Energy needs of adults decrease as they age
• The more active, the more energy required for movement as muscles are contracting more and respiring faster
• During pregnancy, energy requirements increase as energy is needed to support the growth of the developing fetus, add well as the larger mass that the mother needs to carry around. Extra calcium and iron are also needed in the diet to help build the bones, teeth, and blood of the fetus
• Breastfeeding makes energy requirements increase and extra calcium still needed to make high quality breast milk