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Lecture 8 : Lifestyle Factors(2)
Overview
• FOOD COMPONENTS
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Carbohydrates
Fats
Proteins
Minerals
Vitamins
Fibre
Additives
• GEOGRAPHICAL IMPLICATIONS
Food Components
a) Carbohydrates (sugars and starches);
b) Fats (fats, oils, etc.);
c) Proteins (made up from amino acids);
d) Minerals (e.g. calcium);
e) Vitamins;
f) Fibre;
g) Additives.
Major Components
• Carbohydrates. Western diets tend to be too rich in
carbohydrates, especially sugar (which is often used as a
food additive)
• Fats. Western diets are also believed to contain too much
fat. Rates of cancer of the breast, womb and bowel
increase with fat intake.
• Coronary heart disease is also associated with fat-rich
diets. However, it is argued that neither the rise nor the
subsequent decline in CHD rates was associated with
dietary changes.
• Proteins. Proteins are essential for health as they are
broken down into amino acids and reassembled by the
body into new proteins.
Breast cancer rates and fat consumption
Minor Food Components
• Minerals are essential in trace quantities for good health.
• Vitamins are also essential in small quantities. Many
diseases are known to be caused by a deficiency of a
particular vitamin.
• Fibre contains no nutritional value and passes through the
body. However, it is believed to reduce the risk of bowel
disorders. Its bulk also helps reduce the risk of over-eating.
• Additives. Processed food contains various additives (e.g.
stabilisers, emulsifiers, colouring) to preserve shelf-life
and to disguise what might otherwise be unpalatable. Some
are believed to cause health complications.
Vitamin Deficiency Diseases
B1 (thiamine)
Beriberi
B3 (niacin)
Pellagra
B12
Pernicious Anaemia
C
Scurvy
D
Rickets
‘B17’ (nitriloside, laetrile,
amygdalin)
Cancer ?
Geographical Implications
• Diets vary between countries. Malnutrition and undernutrition are obvious factors in global health inequalities.
• Diets also vary within countires. They may therefore
account for some of the observed spatial variations in
health.
• Diet also contributes to social class inequalities in health.
More people in the higher social classes eat the
recommended foods.
Diet And Social Class
A
B
C
D
White Bread
18.0
25.0
28.0
31.0
Brown Bread
4.9
3.4
2.8
3.3
Sugar
9.3
11.0
13.0
15.0
Potatoes
29.0
39.0
49.0
52.0
Fruit
23.0
24.0
20.0
17.0
Ounces consumed per week of different foods by social class (A=high)