NUSC 1165 unit 2 review

What are carbohydrates?

* serve as basis of our diet
* located in variety of food sources

average energy we get from carbs in our diet?

4kcals/g

what is the nutritional impact of carbs?

Nutritional impact of carbs depend on whether its refined or unrefined

what are carbs in the modern diet?

* its a fuel source- they are the preferred source of energy for our brains
* Also primary fuel (first fuel) for body after eating mixed meal \[absorptive state\]

CHO is what?

carbohydrates

CHO is found as energy source for what?

found as energy source for plants in their underground roots and tubers

what is another energy source of CHO?

also found as energy source for developing embryo in seed or grain (endosperm CHO source for germ layer)

what is CHO not found in (based on what we eat)?

CHO not found in meats we eat unless added

what are refined carbs?

foods that underwent processing

What are unrefined carbohydrates?

foods that remain in its natural state

what does nutritional impact depend on?

on whether CHO is refined or not

what are examples of CHO in "Whole Foods"/foods in natural state?

fresh fruits, veggies, dairy, whole grains

what is refining CHO?

separates their vitamins, minerals and fiber

what does refining CHO have effects on?

* Micro-and macro nutrients
* Phytochemical profile
* Glycemic index

what is phytochemical profile?

helps lower inflammation or keep body in health state; have health promoting properties like helping with antioxidants/anti-inflammatory

what is the dietary CHO recommendations for female/male 15-20?

45-65 kcal or 130g

what is enriched flour?

adding nutrients to a product after it was lost during processes

what are the parts of the grain kernel structure?

endosperm, bran, germ

what is the endosperm?

largest portion of grain kernel, contains starch and protein, some vitamins and minerals

what is the bran?

protective outer shell high in fiber and b Vitamins; concentrated source of dietary fiber, vitamins, and minerals

what is the germ?

kernel base, embryo where sprouting takes place, source of vegetable oils and vitamin E

what are refined grains?

made largely from endosperm and mostly starch

in US refined grains are...

- enriched with thiamin, riboflavin, niacin, and iron- fortified with folate (as folic acid)- lacking magnesium, vitamin E, some B vitamins + other nutrients of whole grains

what was the CHO intake in the US like between 1909-1963?

total CHO decreased

decrease in whole grains and fiber (losing some good sources of nutrients)

what was CHO intake like in US from 1960-now?

total CHO increased

* fiber didn't increase with it (means. we have increased consumption of refined carbs; not the healthiest thing)
* ex: high sugars in diet

what is the reasoning behind the increase of CHO in our diet?

mostly due to refined CHO (ex: sugar and increase in white flour/caloric beverages in diet)

how much of refined sugars are in our diet?

~16% of calories in American diet = empty calories

how many calories do we get from beverages?

~400 kcal/day

what is the dangers that come with allowing or having lots of sugar in our diets?

Lots of sugars can reduce life span even if we have healthier diet later on (irreversible damage if over consumed)

what is High-Fructose Corn Syrup (HFCS)?

developed in 1960s

Cheaper, more stable

Not sweeter than table sugar

Highly prevalent in processed foods

is corn syrup worse than table sugar?

pretty identical';

Evidence suggests that one is worse than the other is currently lacking. In other words, they're both equally bad when consumed in excess.

is replacing high fructose corn syrup with table sugar better?

pretty identical; pretty much have same negative effects so doesn’t matter but there is increasing amounts of HFCS in our diets now, which is bad.

what are simple carbohydrates?

broken down quickly by the body to be used as energy

* found naturally in: fruits, milk, and milk products.
* found processed in: refined sugars like candy, table sugar, syrups, and soft drinks.

What are examples of simple carbohydrates?

monosaccharides and disaccharides

what are complex carbohydrates?

made up of sugar molecules that are strung together in long, complex chains

* made up of sugar molecules that are strung together in long, complex chains

what are examples of complex carbohydrates?

oligosaccharides, polysaccharides, starch, glycogen, fiber

what is something that simple and complex carbohydrates share?

Both are turned to glucose (blood sugar) in the body and are used as energy

What are monosaccharides?

simplest forms of sugar and the most basic units from which all carbohydrates are built

* ex: glucose, fructose, galactose

what is glucose?

(blood sugar)

main provider of energy for the body

where can glucose be found?

produced by plants during photosynthesis

in foods: component of disaccharide or starch

what is galactose?

component of lactose. also converted to glucose in liver.

what is fructose?

(fruit sugar)- sweeter taste compared to glucose- fruits, veggies, honey- high fructose corn syrup

What component of the grain kernel stores starch?

endosperm

What are disaccharides?

sucrose, lactose, maltose

what is maltose?

formed when starch broken down in intestine

what is sucrose?

(table sugar): sugar cane, sugar beets, honey, maple syrup

what is lactose?

(milk sugar): occurs naturally in animal foods

What are oligosaccharides?

(3-10 monosaccharides)

* some formed during polysaccharide breakdown in gut- food sources: beans, onions, bananas, garlic, artichokes (prebiotics)
* not digested by enzymes in digestive tract
* nutrient sources for bacteria in gut

what are Polysaccharides??

(often longer than oligosaccharides)

* glycogen
* stored in muscles and liver
* carbohydrate loading

glycolysis is what?

the breakdown of glucose into 2 pyruvate molecules

What is cellular respiration?

Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen

what are steps of cellular respiration?

1. glycolysis
2. acetyl-coA formation


1. citric acid cycle
2. the electron transport chain

what has research shown about carbs and heart disease?

* diets high in sugar may raise blood lipid levels and increase heart disease risk
* diets in whole grains have been found to reduce risk of heart disease

what can soluble fiber help with?

lower cholestrol in the body

What are saturated fatty acids?

Fats with the maximum number of hydrogens (no double bonds)

what are saturated fatty acids made up of?

* comprised of carbon, hydrogen, and oxygen atoms
* contain single bonds in between carbon atoms in their chemical structure

What are unsaturated fatty acids?

Fatty acids made up of one or more double bonds between carbons. They are usually LIQUID at room temperature.

Ex: EPA and DHA in fish oil, ALA in Flax oil.

What are unsaturated fatty acids comprised of?

* comprised of carbon, hydrogen, and oxygen atoms
* they contain one or more double bonds in their chemical structure

are omega fats unsaturated fatty acids?

yes

what are omega fats?

* omega-3
* omega-6
* omega-9

What's the glycemic index?

It's the ranking of how a food affects blood glucose compared to an equal of amount of carbohydrate from a reference food (ex: white bread or pure glucose)

what do numbers of glycemic index mean?

> 70: High Glycemic Index Food

< 55: Low Glycemic Index Food

how do we classify fatty acids?

length and saturation

what are saturated fats?

lipids with single bonds between carbon atoms

what are unsaturated fats?

fats that are liquid at room temperature and they have double bonds between carbon atoms

polyunsaturated fats and monounsaturated fats are what type of fats?

unsaturated fats

what are polyunsaturated fats?

They have at least two double bonds. They make up omega-3 (alpha-linolenic acid) and omega-6 (linoleic acid). They are found in walnuts, flaxseeds, hempseeds, and vegetable oils.

What are monounsaturated fats?

They have one double bond. They make up omega-9. They are found in peanuts and canola oil.

what are the components of lipoproteins?

* fat soluble portion
* water soluble portion
* protein phospholipid
* triglyceride cholesterol (cholesterol + fatty acid)

what makes up lipid transfer and delivery?

triglyceride, cholesterol, phospholipid, protein

What are chlyomicrons?

transports fatty acids from small intestine to the liver. they are the largest lipoproteins and contain greatest proportion of triglycerides

What are VLDLs?

Very Low-Density Lipoproteins (VLDLs): transports endogenous lipids to the tissues; smaller than chylomicrons but still contain a high proportion of triglycerides

what's are LDLs?

they contain higher proportion of cholesterol than do other lipoproteins

What are HDLs?

high density lipoproteins (good/hight cholesterol) → have high protein content

what does a normal artery look like?

wall of normal artery is lined with layer of epithelial cells that are surrounded by smooth muscle

what does a damaged artery look like?

the lining of artery causes inflammation and begins process of plaque formation.

* injury attracts white blood cells, which mature into macrophages, and makes lining more permeable to LDL particles.
* Inside artery wall: LDL oxidized to form oxidized LDL cholesterol.

what is plaque formation in artery?

* inside artery wall: macrophages fill up with oxidized LDL cholesterol → foam cells
* cells get so full they burst, depositing cholesterol.
* accumulation of cholesterol and proteins forms a plaque

what is plaque enlargement in an artery?

* as inflammation continues: plaque builds up, causing artery to narrow and lose elasticity.
* cap of smooth muscle cells and fibrous proteins forms over the plaque, walling it off from the lumen of the artery

what is plaque rupture in an artery?

* if inflammation continues: fibrous cap covering plaque degrades.
* If cap ruptures or erodes: blood clots can rapidly form around it. Then, blood clots can completely block artery at that spot or break loose and block an artery elsewhere

what causes a heart attack?

* blood flow in coronary artery blocked → heart attack results.
* Heart muscle cells cut off from their blood supply and die, causing pain and reducing heart's ability to pump blood

what are the steps that lead to a heart attack?

1. normal artery
2. damaged artery
3. plaque formation
4. plaque enlargement
5. plaque rupture

= heart attack

what is feasting?

storing excess energy

what is fasting?

using energy from stores

what is lipoprotein lipase?

its an enzyme that breaks down the triglycerides from the chylomicron and VLDL into glycerol and fatty acids

what is hormone sensitive lipase?

its an enzyme specific to breaking down stored triglycerides into fatty acts during the fasting state

ATP is used for...

energy

if you skip breakfast, where does your body get ATP?

People burn more calories on days they skip breakfast, but that the habit may increase dangerous inflammation.

what is hydrogenation?

* addition of hydrogen atoms to the carbon-carbon double bonds
* more saturated
* ex: hydrogenated or partially hydrogenated vegetable oils in shortening

what happens to blood glucose regulation during the feasting state?

* insulin released in response to high carb meal
* insulin facilitates uptake and storage of glucose into the muscle, liver, and fat-storing cells

what happens to blood glucose regulation during the fasting state?

* glucagon is released in response to low blood glucose levels
* increased glycogen breakdown to glucose
* increased gluconeogenesis

what is the blood glucose peak?

its a result of the insulin response

the glucose is stored in cells

why does blood glucose dip?

its a result of the glucagon response. the release of glucose from liver into the blood.

what happens when blood glucose dips (body wise)?

feeling hungry, trembling or shakiness, and sweating. In more severe cases, you may also feel confused and have difficulty concentrating.

what happens to glucose during cellular respiration?

* broken down to provide energy
* delivered to tissues via blood stream

chemical formula for chemical respiration?

C6H12O6+6O2 →6CO+6H2o+ATP

What is hydrolysis?

the chemical breakdown of a compound due to reaction with water.

What is dehydration?

insufficient amount of tissue fluid

What is a dehydration reaction?

when two monomers bond together through the loss of a water molecule

hydrolysis and dehydration synthesis:

breaking down and building of molecules using water

What are triglycerides?

This term refers to the body's most concentrated energy source and the form in which most fats are stored in the body.