Revision:Diet and Health

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Discuss the significance of diets that are rich in lipids

Discuss the significance of diets that are rich in lipids, in relation to obesity and coronary heart disease.

• Obesity is 20%+ average body weight for particular height
• Lipids are essential energy source and needed for protection and insulation
• Excess lipids may lead to coronary heart disease

Discuss the Significance of saturated and unsaturated lipids in relation to a healthy diet

• Unsaturated fats (olive oil, peanuts, avocados) are better than saturated fats which (as meat, dairy products) raise cholesterol levels and the chance of angina or heart attack

Outline how the body synthesises and uses Cholesterol

• Cholesterol is a hydrophobic lipid
• Found in membranes of cells
• Essential for functioning of plasma
  • Limits uncontrolled leakage of small molecules
  • Pulls together the fatty acid chains in phospholipids, restricting their movement
  • Used in the liver to make blue salts
• One molecule contains 4 rings of carbon and hydrogen atoms
• One OH^- atom gives the molecule a small negative charge as a result of ionisation

Discuss the Effect of additional dietary cholesterol

• Additional dietary cholesterol may lead to deposits of crystalline collusion and droplets of cholesterol esters.
• May cause thickening of Artery wall (atherosclerosis)
• May lead to heart attack from blocking of Coronary arteries, strokes (brain arteries blocked)

Discuss the main features of the variety of Vegetarian diets

• Vegans No animal products
• Lacto-Vegetarian may eat dairy produce
• Pesco-Vegetarian May eat fish
• Ovo-Lacto Eggs and Diary produce

Explain how these diets can achieve a balance

• Protein Nuts, eggs, beans
• Fats Oils, Avocados

Explain the possibility of Deficiency of Iron, Calciferol, Cyanobalamin

• Fe - Spinach, Egg yolk, green vegetables
• Ca - Water, Fish, Milk derivatives
• Calciferol (D) - Liver Oils
• Cyanobalamin - eggs and dairy produce

Define malnutrition

• The result of feeding on a diet that is not balanced.

Outline the Causes of Malnutrition

• Social - Anorexia
• Economic
  • Too much - America
  • Too little - Bangladesh
• Cultural - Snack food
• Environmental - Natural disasters

Discuss one example of global malnutrition using published data

Discuss Nutritional issues of Osteoporosis

• Disease characterized by the thinning of bones, with a consequent tendency to sustain fractures from minor stresses.
• The disorder is most common in women over the age of 50.
• Results from disturbances of mineral metabolism and nutrition.
• Osteoporosis results from changes in the balance between the amount of new bone that is formed within the body and the amount of bone that is reabsorbed, or broken down and assimilated. The latter process occurs because calcium in the bones is regularly drawn upon to maintain the calcium that circulates in the bloodstream and is needed for normal nerve and muscle functions. When, for whatever reason, the body has insufficient other supplies of calcium to draw upon, it will draw on the calcium held within the bones, and, as the calcium reservoir in the bones decreases, bone loss ensues. In persons with osteoporosis, the rate of bone formation is normal but bone resorption is accelerated, leading to a net loss of bone mass.

State the uses of chemical additives

Chemical additives can act as

• Preservatives
• Antioxidants
• Colouring
• Flavouring
• Acid-regulators
• Stabilisers

State that some additives may have deleterious effects and that Consumer protection necessary

Explain the Importance of hygienic methods of food handling

• Keep raw meat away from cooked meat
• Sterilise work surfaces
• Prevent spread of pathogens

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