This presentation addresses the dietary factors responsible for the development of certain non-communicable diseases.

1. NUTRITIONAL FACTORS
IN
SELECTED DISEASES
DR. FAIZA LIAQAT

2. CARDIOVASCULAR DISEASES
• Plasma cholesterol has a very high statistical significance with the
incidence of CHD.
• Various studies have supported the role of elevated blood levels of
cholesterol and low density lipoproteins (LDL) in the development of
atherosclerosis.
• Greater intake of polyunsaturated fatty acids (PUFA) and less intake of
saturated fats, while restricting the intake of fat calories to less than 30% of
the total calories, may lower the risk that CHD will subsequently develop.

3. 1. CHOLESTROL:
• Cholesterol occurs in all foods of animal origin.
• The plasma cholesterol is determined by:
a. the amount absorbed from food
b. the amount synthesized in the body
c. the rate of catabolism and excretion in the bile
d. intestinal reabsorption of bile acids
e. the equilibrium between plasma and tissues.

4. 2. LIPOPROTEINS:
Cholesterol is carried in plasma lipoproteins.
• VERY LOW DENSITY LIPOPROTEIN (VLDL): Dominated by its triglyceride
content. (risk factor for CHD)
• LOW DENSITY LIPOPROTEIN (LDL): Dominated by its cholesterol content.
(involved in atherosclerotic process)
• HIGH DENSITY LIPOPROTEIN (HDL): Functions in removal of cholesterol from
cells. (protective effect in CHD)

5. 3. FATTY ACIDS:
• SATURATED FATTY ACIDS: increase plasma cholesterol.
• UNSATURATED FATTY ACIDS: lower plasma cholesterol.
• POLY-UNSATURATED FATTY ACIDS: inhibit platelet aggregation (prevent thrombus).
4. TRIGLYCERIDES:
• Blood concentration is markedly increased in individuals with raised cholesterol level.
(risk factor for CHD).
• The most important determinant of TG level is the activity of the enzyme, lipoprotein
lipase in the endothelial lining of the capillaries and in a variety of tissues. This enzyme
removes TG from VLDL and converts these to the lipoproteins of higher density.

6. 5. CARBOHYDRATE:
• Coronary heart disease rates are lowest in populations eating high
carbohydrate diets.
• Fiber intake decreases the risk of CHD.
6. SALT:
• Highest incidence of hypertension is seen in Japan because of sodium intake
more than 400 mmol/day.
• Hypertension can be treated with low sodium diet. (less than 10 mmol/day)

7. DIABETES
• In a diabetic, there is impaired metabolism of glucose in the body which leads
to excess of glucose in blood and urine.
• Insulin deficiency leads to accelerated utilization of energy reserves from fat
stores.
• Due to insulin deficiency excess of fatty acids are converted to triglycerides.
• Studies in England showed that diabetics ate an average 1000 kcal per day
more than non-diabetics.

8. OBESITY
• The basic cause of obesity is overnutrition.
• A diet containing more energy than needed may lead to prolonged
postprandial hyperlipidemia and to deposition of triglycerides in adipose tissue
resulting in obesity.
• A relative insulin resistance takes place in obesity in peripheral tissues, mainly
adipose tissues, while the insulin secretion is normal or increased.

10. CANCER
A. DIETARY FAT:
• Population surveys have shown a strong positive correlation between cancer colon
and dietary intake of fat.
• Dietary fat is believed to increase the secretion of bile acids in the bowel which are
then metabolized by bacterial flora into carcinogen or co-carcinogens.
• A positive correlation between per capita consumption of dietary fat and breast
cancer rates has also been noted. A reduction in dietary fat may alter the risk of
breast cancer perhaps by increasing estrogen production or prolactin release.

12. B. DIETARY FIBER:
• Several studies indicate that the risk of colon cancer is inversely related to the
consumption of dietary fiber.
• It may protect against intestinal carcinogens or precursors by dilutional or other
effects.
C. MICRONUTRIENTS:
• Micronutrients may also have a protective influence since cancers of the lung and
several other sites have been associated with a low intake of vitamin A.
• The risk of stomach cancer has been related to a deficiency of vitamin C which
may act by inhibiting the formation of carcinogenic nitrosamines in the stomach.

13. D. FOOD ADDITIVES AND CONTAMINANTS:
• Food additives and contaminants (e.g., preservatives, artificial colors, artificial sweeteners,
pesticides, flavors, anti-oxidants) have always been under suspicion as possible
carcinogens in their long-term effects.
• Nitrosamines are responsible for certain types of gastric carcinoma.
• Aflatoxin is a carcinogenic metabolite.
• Coffee intake has been associated with bladder cancer and recently with pancreatic cancer
but causal relationships have not been established.
E. ALCOHOL:
• Heavy drinking increases the risk of liver cancer.
• It is estimated that alcohol contributes to about 3% of all cancer deaths.
• Beer consumption may be related to cancer rectum.