lecture 6

• Minerals


  Inorganic substances needed by the body for many different functions
• Macrominerals


  • Ca, P, Mg, Na, K, Cl, S
• Microminerals (Trace)


  • Fe, Mn, Cu, I, Zn, Co, F, Se, Cr, Mo
• Calcium (Ca)


  The most common mineral in the human body, most of it found in bones and teeth
• Functions of Calcium


  • Bone and tooth construction
  • Blood coagulation
  • Transport of nerve impulses
  • Muscle contraction
• Poor intakes of calcium

  Can result in poor bone health which can increase the risk of diseases such as osteoporosis later in life
• Taking high doses of calcium supplements

  Can cause stomach pains and diarrhoea
• Too much calcium


  Has been shown to increase the chances of atherosclerosis and kidney stones
• Food sources of Calcium

  • Milk & dairy products
  • Fish with bones
  • Molasses
  • Oil seeds
  • Green leafy vegetables
  • Legumes
  • Dried fruits

  
• Vitamin D


  Regulates the amount of calcium available, lack of vitamin D results in reduced absorption of Ca
• Phosphorus (P)


  Essential for the structure of bones and teeth, cell membranes and for energy metabolism
• Food sources of Phosphorus

  • Red meat
  • Dairy products
  • Fish
  • Poultry
  • Bread
  • Rice
  • Oats

  
• Magnesium (Mg)


  Helps in the osmotic balance and acid-base balance, has an important role in maintaining blood pressure, works with Ca & P for bone and teeth health, important for muscles & nervous system
• Food sources of Magnesium

  • Nuts
  • Legumes
  • Grains
  • Cheese
  • Dark green leafy vegetables
  • Cocoa
• Magnesium deficiency symptoms


  • Muscle cramps & spasms
  • Problems with teeth & bones
  • Cocoa cravings! (menstrual cycle)
• Fluoride (F)


  Needed for the formation of strong teeth and protects against dental decay (caries), a trace element so only a small amount is required
• Food sources of Fluoride


  • Drinking water
  • Tea
  • Saltwater fish
  • Fluoride toothpastes
• Excessive intake of fluoride

  Can lead to mottling or discolouration of teeth, and has been associated with cancer formation in some studies
• Iron


  Its main function is to carry oxygen, needed for the formation of haemoglobin in red blood cells which transports oxygen around the body, essential for cognitive performance
• Non-haem iron absorption


  Vitamin C aids absorption, drinking coffee with or after meals may reduce absorption
• Iron deficiency


  Leads to anaemia with symptoms like feeling of tiredness, lacking in energy, general weakness, poor concentration, paleness
• Excessive iron intake


  Can result in constipation, nausea and vomiting
• Zinc (Zn)


  Essential for normal growth & reproduction and immunity, aids the action of many enzymes
• Food sources of Zinc


  • Protein-containing foods, meat, fish, oysters, peanuts, sunflower seeds

  
• Zinc deficiency


  Leads to loss of appetite, impaired growth and development, skin disorders, white spots on fingernails, loss of taste sensation, poor immunity
• Selenium (Se)


  An antioxidant mineral that protects cells against free radical damages, vital for normal sexual development
• Food sources of Selenium

  • Meat, fish, dairy foods, nuts, avocados, lentils

  
• Excessive selenium


  Can cause hair loss, skin depigmentation and fatigue
• Chromium (Cr)


  Important for the regulation of blood glucose levels, helps reduce sugar cravings, helps regulate blood cholesterol levels
• Food sources of Chromium


  • Red meat, liver, egg yolk, seafood, wholegrain cereals, molasses, cheese

  
• Chromium deficiency


  Can lead to glucose intolerance, increased sugar cravings, raised blood cholesterol levels
• No adverse effects are reported for excess chromium consumption
• Potassium (K)


  Essential for water and electrolyte balance, important for normal functioning of cells, including nerves and muscles, important for the functions of heart muscle
• Food sources of Potassium

  • Fruits (dried fruits, bananas, berry fruits), leafy green vegetables (e.g. broccoli and spinach), meat, nuts, seeds, pulses, coffee

  
• Potassium


  Important in counteracting the harmful effects of Na in hypertensive patients
• Sodium (Na)


  Important for fluid balance, acid-base balance, nerve-muscle work, cell permeability
• Sources of Sodium


  • Table salt, baking powder, baking soda, soy sauce, processed meats, olives, pickles, salty cheese
• Sodium deficiency


  Unlikely, but can be caused by excessive sweating or vomiting and diarrhoea
• Iodine (I)


  Needed by the thyroid gland to produce hormones that regulate basal metabolic rate
• Food sources of Iodine

  • Seafood, iodised salts