Chapter 7 Diet and the Prevention of type 2 Diabetes

Question 0

What is the prevalence and incidence of type 2 diabetes? 7.2.1

Answer 0

Risk for individuals born in the US in 2000 is 32.8% for men and 38.5% for women.
lowest rate found in rural communities where people retain traditional lifestyles
Ethnic groups more at risk:
asian indians, hispanics, native americans

Question 1

What are the 6 key points of diet and the prevention of type 2 diabetes? (ch 7)

Answer 1

1. prevalence of type 2 diabetes is increasing rapidly in all parts of the world.
2. obesity and physical inactivity are major modifiable risk factors
3. Cohort studies indicate that cereal fibre a major source of insoluble fibre is most potent for preventing diabetes, WHEREAS intervention studies indicate that soluble fibre is most effective
4. cohort studies shows an association between the glycemic index and the glycemic load of the diet and the risk of diabetes
5. saturated fat appears to increase the risk whereas polyunsaturated fat appears to be protective
6. Diets poor in mg may increase the risk of diabetes

Question 2

What are some metabolic changes that occur during he development of type 2 diabetes? 7.3

Answer 2

• resistance to action of insulin
• beta cells of pancreas respond by increasing output of insulin in order to maintain normal glucose levels.
• early stages of the disease glucose tolerance may be normal but hypersecretion of insulin is usually insufficient to maintain normal glucose levels indefinitely
• now gradual progression to impaired glucose tolerance (IGT) and IFG (impaired fasting glycemia)
• insulin secretion declines at a variable rate and disease progresses to overt diabetes

Question 3

What are some of the metabolic abnormalities that impaired glucose tolerance (IGT) and increased fasting glycemia (IFG) and type 2 diabetes associated with?

Answer 3

central obesity,
hypertension
hyperuricemia
increased plasminogen activator inhibitor-1
abnormal blood lipid pattern–increased triglycerides and decreased HDL cholesterol

Question 4

What is the role of obesity in the development of Type 2 Diabetes? 7.5.1

Answer 4

risk of diabetes is 20 fold greater in obese women.

distribution of body fat is a more reliable predictor…abdominal fat is at greater risk.

Question 5

What is the role of physical inactivity in the development of Type 2 diabetes? 7.5.2

Answer 5

inactivity leads to obesity etc.
guidelines used today typically recommend moderate exercise on at lease 5 day/week but do not specify target heart rate ranges.
possibly vigorous exercise is required to increase insulin sensitivity.

Question 6

what is the relationship between saturated fat and type 2 diabetes? 7.5.7

Answer 6

saturated fat has been associated with poor glucose tolerance and higher fasting levels of both glucose and insulin
Whereas the intake of polyunsaturated fat has been associated with lower fasting and 2h glucose levels and lower risk of type 2 diabetes

Question 7

What is the recommendations on magnesium for Type 2 diabetes? 7.5.8

Answer 7

there have been several studies that indicate mg has a strong inverse relationship with the association of type 2 diabetes…however in the absence of any randomized clinical trials it would be premature to make specific recommendations concerning mg intake.

Question 8

What is the relationship between fibre intake and blood insulin levels? 7.5.4

Answer 8

inverse relationship.
most pronounced effects is with soluble fibre.
studies have shown a need approx 24-26.5 g fibre in women and 29.7g in men
recommendation is to eat generous amounts of whole grain cereals, legumes, vegetable and fruit.

Question 9

Discuss the potential value of giving advice on GI and GL of specific foods for type 2 diabetes. 7.5.6

Answer 9

evidence is quite strong that a diet with a high GI and GL can increase the risk of diabetes but according to the textbook this does not constitute a strong reason to incorporate this into dietary recommendations because there is a lack of strong evidence for an association with other health problems such as obesity.
Also it is confusing for people to follow recommendations for a low GI diet and mixed dishes are hard to define GI values
Therefore it is encouraged that people simply follow the well established diet recommendations.

Question 10

What is the appropriate intervention strategy for the prevention of type 2 diabetes? 7.7

Answer 10

have daily recommended amount of fibre esp soluble fibre, limit sugary beverages,
daily recommended protein, diet higher in polyunsaturated fats and low in saturated fats.
exercise regularly to try to lose weight 1 hr/day
some studies have shown that replacement of foods with a high GI with that of lower GI is another beneficial step