What are Nutrients?

There are over 40 recognized nutrients but I will highlight the main ones and their bodily functions that exist in food that will help in useful physiological roles:

3 main classes of nutrients supplying energy to our body

  • Carbohydrates (50-60%) – main energy for the brain and nervous system – cereal, potatoes, sugar, grains, veg.
  • Fats(30% of which less than 10% from saturated fats) – main energy source for musles, incl heart muscle, provides essentially fatty acids – meat, dairy products, oily fish, nuts, oil.
  • Protein (20%) – main material of cells, assist in growth, repair ,( mainly amino acids) – nuts and pulses, meat, fish, eggs. dairy, cereal.

2 types of vitamins required in smaller amounts than the 3 main nutrients but play important roles to facilitate processes through the body

Calcium – important for bones and teeth, muscle contraction, nerve transmission, immune function – milk, soya bean products, cheese, greens, bread.

Vitamin A
Main structure and function of skin, body linings (lungs, vision, immune) – liver, cheese, carrots, dark green, mango.

Vitamin D
Helps absorption and regulate calcium in the blood, bone formation and repair – oily fish, egg yolk, sunlight on the skin.

Vitamin E
Protects body cells against damage, oxidation – veg, veg oils, seeds, almonds, wheat germ, peanut butter, avocado.

Vitamin K
Essential for clotting of blood to bind calcium for bone, musles n kidneys – green leafy veg, meat, veg oil, cereals, dried seaweed.
Water-soluble vitamins (excreted daily)

Vitamin B1 (Thiamin)
Helps release energy from carbohydrates, involved in nervous system and heart – whole grains, nuts, meat (esp pork) , fruits, veg, fortified cereals.

Vitamin B2 (Riboflavin)
Helps release energy from protein, carbo and fat. involved in transport and metabolism of iron – milk, eggs, rice, liver, greens, mushrooms.

Vitamin B3 (Niacin)
Helps release energy from food, nervous system – most foods , esp meat.

Vitamin B6
Involved in metabolism of protein and transport iron in body – beef, white fish, poultry, whole grains, eggs, avocado, banana

Vitamin B12
Important for the blood, nerves, prevents folate defidiency and helps release energy from food – milk, meat, liver, oysters, eggs, fortified cereals, green leafy veg

Vitamin C
Important for wound healing, maintain body tissues, helps absorp iron, antioxidant – fresh fruits, esp citrus, green veg, tomatoes, new potatoes.

Major Minerals (vital to health, co-factor in body metabolism, growth, water balances and other processes)

Calcium – important for bones and teeth, muscle contraction, nerve transmission, immune function – milk, soya bean products, cheese, greens, bread.

Phosphorous – for bones and teeth, genetic process, energy transfer – found in many foods.

Magnesium – protein synthesis, muscular contraction, transmission of nerve impulses, bone mineral – wide spread, esp in greens, grains and nuts, tofu, cashews, sunflower seeds.

Sodium and Potassium – electrolytes that maintain fluid balance and involved in energy utilization and nerve function – banana, shellfish, milk, raisins, baked potato, asparagus (potassium)

Trace Minerals (constitute very little in the body but very interactive with the absorption and metabolism of other minerals)

Iodine – to make thyroid hormones, esp growth of early foetus – seafood, milk, seaweed, iodised salt.

Fluoride – formation of bones and teeth , prevents tooth decay – Fluoridated water, tea, toothpaste.

Selenium – antioxidant, immune system function – cereals, meat, brazil nuts, cheese, eggs, canned tuna, shrimp.

Iron – needed for red blood cells, carries oxygen, metabolism and removal of substances from the body – liver, meat, beans, nuts, dried fruits, poultry, fish, whole grains, dark greens.

Zinc – essential for cell division, immune reactions, taste perception, wound healing, making of sperm, development of foetus – milk, cheese, fish, wholegrain, pulses, lamb, steak.