Dietary Carbohydrates Flashcards
What is glycemic index?
The change in blood glucose that occurs from eating food; high-glycemic index raises your blood glucose a lot, while low-glycemic index raises your blood just a little.
What is a major limitation of the glycemic index?
It only captures blood glucose – not fructose.
The best studies for evaluating the health effects of diet are ________________.
long-term interventional studies, in which one group receives an intervention (such as telling them to eat healthy and exercise) and one doesn’t
What four things have been associated with increased risk for diabetes?
- Increased intake of dietary carbohydrates
- Increased intake of high-fructose corn syrup
- Reduced intake of whole grains
- Obesity (which is also associated with carbohydrates)
Uniquely, fructose can cause _______________.
insulin resistance in the absence of weight gain
How does fructose metabolism differ from glucose metabolism?
Fructose bypasses the regulatory enzyme phosphofructokinase and goes into the TCA cycle. Thus, it can add to TCA cycle energy production or lipogenesis without being regulated.
The greatest risk for development of diabetes seems to come from ______________.
a diet rich in high glycemic index food and low in fiber
For a 70 kg person with an average energy expenditure, energy intake should be roughly ________.
2,100 kcal/day
What percent do the macronutrients make up in a typical person’s diet?
Protein: 15%
Fats: 30%
Carbohydrates: 55%
The average American consumes _______ per day in added sugars.
94 grams
What three things make fructose problematic in sugar metabolism?
Its entrance is not regulated by insulin.
It bypasses phosphofructokinase and thus passes straight into the TCA cycle (increasing triglyceride levels through lipogenesis).
It does not stimulate a rise in insulin release.
What chemical structure explains the high glycemic index of starchy foods such as white bread, potatoes, and pasta?
Amylopectin – a highly branched polysaccharide that allows many points of catabolic degradation
True or false: insoluble fiber creates more bulk than soluble fiber (gram for gram).
False. Soluble fiber absorbs water and thus achieves a larger bulk than insoluble fiber.
Ultimately, the Finnish trial and other gold-standard trials have shown that diets with ______________ are best at preventing diabetes.
high carbs but low calories
(this effect might be due to weight loss, as other trials have shown that low-carb and low-calorie diets are even better at preventing diabetes)
