Nutrition Final: Carbohydrates

What is the problem with small frequent meals?

potential for overeating, increased caloric intake

What is a glycated protein?

protein with a sugar/carbohydrate molecule bonded, without the controlling action of an enzyme

Why is carbohydrate protein-sparing?

-carbs preserve lean muscle mass -body can burn carbohydrates for energy and does not need to burn muscle protein

Compare and contrast HFCS and sucrose?

-chemically, not much difference, HFCS-55 nearly identical to sucrose -sucrose doesn't have a bad reputation, increases blood glucose -fructose doesn't increase blood glucose -HFCS contains "free" fructose and glucose

Why do cocoa puffs have a lower GI than corn flakes?

-cocoa puffs are glucose and sucrose -corn flakes are just glucose

Why is a high-fiber diet beneficial?

-disease prevention --soluble fiber is hypoglycemic, hypolipidemic --insoluble fiber is nonfermentable 00 prevents diverticular dz, gallstones, IBS, constipation --colon cancer prevention -increased satiety

How does fructose induce lipogenesis?

-fructose processed through liver --> liver converts it to triglycerides -fructose blocks glucose metabolism in liver and synthesis of glucose into glycogen --> creates glucose traffic-jam in liver

Glycemic Load information

-high GI and low GL: low amount of carbohydrate per serving -low GI and high GL: high amount of carbohydrates per serving

What is protective pathway of glucose metabolism?

-liver says "do i use it, or store it?" -excess sugar not needed at that moment is metabolized, and is converted into fat ---> converts sugar into glycogen --> uses necessary glycogen for energy --> unneeded glycogen converted into fat (triglycerides) -excess glucose in blood is toxic, fat is less damaging in blood than sugar

Does fiber decrease risk of colon cancer?

-not necessarily -cultures with high-fiber diets show lower rates of colon cancer -short-term trials increasing rates of fiber do not show change in colon cancer rate -some evidence that soluble fiber degradation releases carcinogens, decreased absorption of bile salts may put GI epithelium at risk

What is the flaw of chronic disease epidemiology

-refinement of carbohydrates and high consumption of them confounds ability to test hypothesis that high fat intake, animal fat intake, and low carbohydrate intake causes diseases -increased sugar consumption since-mid 19th century was a huge change

How does the liver work to maintain blood glucose?

-removes glucose from blood for glycogen synthesis or energy release -glycogen stored in liver and can return glucose to blood (gluconeogenesis, glycogenolysis) -hormonal influence from other organs also helps to regulate --> pancreatic insulin, glucagon; glucocorticoid hormones of adrenal cortex

What is nutrition transition?

-shift from native/indigenous food culture to more affluent diet (more calories, fat)

What are simple strategies to balance blood glucose?

-small frquent meals (graze) -eat fewer carbohydrates -eat more fat

What is resistant starch?

-starch that escapes digestion in the small intestine -third type of fiber: benefits of both soluble and insoluble fiber -both a dietary and functional fiber -varies glycemic response

What is difference between sugar and starch?

-sucrose (sugar): 50/50 glucose and fructose -starch: 100% glucose

What is the second meal effect?

-the effect the first meal has on blood glucose level after eating the second meal -looks at entire diet pattern instead of individual food selections -looks for blood sugar disregulation issues through the day

What is a side effect of excessive sugar alcohol intake?

GI side effects

What is the difference between glucose and fructose?

Glucose: raises blood glucose, increases leptin and insulin levels Fructose: no increase in blood glucose, no increase in leptin or insulin levels -- increases load on liver

What is difference between glycemic index and glycemic load?

Glycemic index: measure of the quality of a carbohydrate. Qualitative comparisons of carbohydrate Glycemic load: measure of a quantity of carbohydrate impact on blood sugar. Quantitative impact of carbohydrate on blood glucose.

Rank simple carbohydrates according to sweetness

Most sweet to least sweet: 1. Fructose 2. Sucrose 3. Glucose 4. Maltose 5. Lactose

What are problems with glycemic index?

focuses on blood glucose, not potential burden of fructorse

What is an important glycated protein and what is it used for?

hemoglobin A1c is a glycated component of hemoglobin --> used to monitor 3 month glucose levels

Glycemic index information

high GI foods: digested quickly, causes rapid rise in blood sugar Low GI foods: digested slowly, cause a slow rise in blood sugar

How do carbohydrates improve sleep?

insulin carries tryptophan into the brain to make serotonin and melatonin

How are high carbohydrate native diets protective against diabetes and obesity?

low refined food intake

What are the 5 artificial sweeteners available in the US?

1. aspartame (nutrasweet, equal) 2. saccharine (sweet n low) 3. sucralose (splenda) 4. acesulfame potassium (sweet one) 5. neotame -- more heat stable than aspartame

list the adverse effects of dietary fructose

1. fructose is a potenti reducing sugar --> strong potential for oxidation-reduction reaction, easily reduces and causes glycation --> aging, diabetes, renal and CV concerns 2. non-alcoholic fatty liver disease 3. fxnl bowel disturbances --> fructose malabsorption can occur with people who eat more fructose than glucose 4. metabolic syndrome (aka syndrome X, pre-diabetes) -hypertension, elevated triglycerides and subsequent LDL, insulin resistance 5. no increase in leptin or insulin levels --> no hormonal trigger of satiety

Compare and contrast the 2 basic treatment approaches to diabetes

1. improve the function of insulin on the cell membrane --increase exercise, decrease small dense LDL, oral hypoglycemics 2. lower insulin by decreasing carb consumption --fructose and alcohol reduction, starch reduction

What is carbohydrate hypothesis?

1. obesity caused by regulatory defect in fat metabolism 2. insulin plays primary role in fattening process, and resulting hunger and fatigue 3. carbs lead to the chronic elevation of insulin --> especially refined carbohydrates and fructose

How can you lower glycemic response?

1. reduce starch gelatination 2. foods with fibrous coat: beans, seeds, grains - slows digestion 3. high amylose content (resistant starch) - basmati rice, legumes 4. larger particle size 5. viscosity of fiber --> soluble fbers increase viscosity, lower the GI 6. sugar (sucrose) restricts starch gelatinization, causing lower GI 7. acidity --> sourdough, lemon juice, vinegar. Acids slow down gastric emptying, lower GI 8. increase fat --> slows down gastric emptying, lower GI

What is the difference between water-soluble and water-insoluble fiber?

Water-soluble: dissolves in hot water -delays gastric emptying, increases transit time (slower movement), decrease nutrient absorption Water-insoluble: doesn't dissolve in hot water -decrease transit time, increases bulk

What are the 2 other sweeteners used in the US?

1. stevia 2. xylitol: non-fermentable sugar alcohol, GI side effects

What is monosaccharide composition of sucrose?

2 carbohydrates - disaccharide -fructose + glucose

What is monosaccharide composition of lactose?

2 carbohydrates - disaccharide -galactose + glucose

What is the monosaccharide composition of starch?

8+ carbohydrates - polysaccharide -glucose

How does weight gain protect against diabetes

Excess glucose is stored as adipose tissue and does not enter the blood stream