Nutrition (Week 4--Pregler) Flashcards Preview

Block 3: GI, Endocrine, Reproductive > Nutrition (Week 4--Pregler) > Flashcards

Flashcards in Nutrition (Week 4--Pregler) Deck (20):
1


What were people told to eat in the 1980's and 1990's?


Food pyramid

High carbohydrate, low cholesterol, low fat

(USDA makes food pyramid and has grain lobbyers)

2


What did the advice to eat lots of carbohydrates do?


Caused people to become obese and thus get Type 2 Diabetes

3


What is the Mediterranean diet?


38% fat (but monounsaturated)

42% carbohydrates

20% protein

Associated with lower risk of CAD than typical Western diet or low fat diet

4


What happened when an Israeli study compared a low fat diet, Mediterranean diet, and low carb diet?


The low carb diet (Atkins) had the most weight loss, lowest TGs, lower LDL, highest HDL

Low fat diet was the worst

5

Monounsaturated fats

TGs containing fatty acids with one double bond

Good!

Associated with low LDL and high HDL

Get it from olive oil, canola oil

6


Polyunsaturated fats


Omega-6 fatty acids: lower LDL and HDL, but controversial because may cause CVD if higher omega 6 to omega 3 ratio; in nuts, avocados, olives, soybeans

Omega-3 fatty acids: little effect on LDL, HDL but reduce TGs, suppress cardiac arrhythmias, lower BP, reduce cardiovascular mortality; in fish oil, plants

7


What determines your cholesterol levels?


More intake of fatty acids than dietary cholesterol

8


Essential fatty acids


Linoleic acid (omega-6 fatty acid; precursor to prostaglandins, leukotrienes, thromboxane)

Alpha-linolenic acid (omega-3 fatty acid)

Make sure these are in formula for babies or parenteral IV nutrition for people in hospital

9


Are there essential carbohydrates?


No!

We only need glucose (and this can be made from AAs, other things?)

10


What does fiber do?


Soluble fiber forms viscous gel when mixed with liquid so delays gastric emptying

Lowers LDL by increasing fecal bile acid excretion and interfering with bile acid reabsorption

Absorbs 10-15 times its weight in water, decreases risk of constipation, hemorrhoids

11


What does it mean to have a high glycemic index?


Means once you eat it, your blood sugar level spikes higher and faster ("gusher"), as opposed to lower and longer ("trickler")

12


What type of diet caused people to gain LESS weight?


High protein

Low glycemic index

13


When do we tend to see severe nutritional problems?


If you eat only one type of food

Alcoholics who don't eat because get calories from alcohol

14


Athletes or body builders on high protein and very low carb diet will have what problem?


Brain needs glucose so will deaminate AAs to get glucose and will degrade tissue proteins to get it

15

Water soluble vitamins


B complex necessary for energy release

Folic acid and B12 necessary for hematopoesis

B6 necessary for AA metabolism and other enzymatic reactions

Vitamin C (ascorbic acid) is antioxidant, co-factor for formation of collagen

16

Fat soluble vitamins


Vitamin A: vision, growth, spermatogenesis, maintenance of fetus, differentiation of epithelial cells

Vitamin D: Ca2+ and phosphate homeostasis, bone formation, maybe immune response to specific organisms

Vitamin E: antioxidant

Vitamin K: clotting

17


Water soluble vitamin deficiencies


B1 (thiamine) in alcoholics esp with gastric bypass

B6 (pyridoxine, pyridoxamine, pyridoxal) in homeless people taking isoniazid (for TB)

B12 in elderly with autoimmune destruction of parietal cells so no intrinsic factor, or vegans or gastric bypass

Folic acid (not anymore because grain enriched)

18


Fat soluble vitamin deficiencies


Vitamin D in elderly women

Vitamin K in newborns (no intestinal bacteria), people with liver disease, malnourished

19


Should "food secure" people take vitamins?


Hasn't shown to be effective (except folic acid to prevent birth defects and maybe vitamin D)

20


Does taking B vitamins to lower homocysteine lower risk for CVD?

Lowers homocysteine, but does NOT reduce risk for CVD

Example of how mechanism should cause certain outcome but does not