Nutrition Flashcards
T or F? Overweight and obese individuals have relatively low metabolic rates.
False
T or F? Low metabolism contributes significantly to obese individuals’ excess weight gain.
False for most populations
T or F? There are diets available to increase a person’s metabolic rate thereby inducing weight loss.
False
T or F? A person’s metabolic rate decreases during caloric restriction inhibiting the rate of weight loss.
True
What is an alternative energy source for the brain?
Beta-hydroxybutyrate (ketones)
What is stunting and what is it caused by?
It is linear growth failure caused by chronic mild protein energy malnutrition
What is the meaning of underweight?
Defined as weight-for-age >2 SD below mean in kids, BMI<18.5 in adults
What is the meaning of wasting?
It is AKA marasmus and is defined as weight-for-height >2 SD below mean
What is Kwashhiorkor?
Manifested by inadequate protein and it causes wasting with edema and impaired renal function
What are saturated FAs?
No double bonds
What are mono unsaturated FAs?
Single double bond
What are poly unsaturated FAs?
Multiple double bonds
What happens with essential FA deficiency?
Scaly dermatitis
What are the essential FAs?
Linoleic and Linolenic Acid
How does fiber decrease plasma cholesterol levels?
- Sequesters bile to reduce reabsorption
- Slows carbohydrate absorption which keeps insulin low and slows cholesterol synthesis
- Stimulate short chain FA synthesis which inhibits cholesterol synthesis
What are the fat soluble vitamins?
A, D, E, K
What are the water soluble vitamins?
Thiamin, riboflavin, niacin, B6, B12, pantothenic acid, biotin, folic acid, vitamin C
What are the functions of vitamin A?
Involved with vision and gene expression
What happens with vitamin A deficiency?
Night blindness/red gingiva/immune dysfunction
What are the functions of vitamin D?
Maintain serum calcium and phosphorus levels
What happens with vitamin D deficiency?
Rickets/osteomalacia
What are the functions of vitamin E?
Antioxidant in cell membranes
What happens with vitamin E deficiency?
Ataxia with peripheral neuropathy
What are the functions of vitamin K?
Cofactor for blood clotting
What happens with vitamin K deficiency?
Hemorrhaging and poor coagulation
What is a major sign of rickets?
Bow legs
What is vitamin A AKA?
Retinol
What is vitamin D AKA?
Cholecalciferol
What is vitamin E AKA?
Tocopherol
What is vitamin K AKA?
Phylloquinone
What vitamin first comes to mind with chronic alcoholism?
Thiamin
What important enzyme is thiamin a cofactor for?
Pyruvate dehydrogenase
What disease is related to thiamin deficiency?
Beriberi
What enzyme is most affected by riboflavin deficiency?
Succinate Dehydrogenase
What is a symptom of excess riboflavin?
Bright yellow urine
What is niacin made from?
Tryptophan
What is the function of niacin?
Coenzymes as NAD and NADP in ATP synthesis
What is caused by niacin deficiency?
Pellagra
What is the function of vitamin C?
Coenzyme in redox reactions (hydroxylation of collagen)
What is caused by vitamin C deficiency?
Scurvy
What is the function of folic acid?
Coenzyme for methyl transfer reactions (THF)
What important enzymes are related to folic acid?
Thymidylate Synthase
Methionine Synthase
What is the function of cobalamin?
Coenzyme for one-carbon transfers: methionine synthase & methylmalonyl-CoA mutase (methylmalonyl CoA to succinyl CoA)
What is caused by cobalamin deficiency?
Decreased DNA synthesis and increased MeTHF as a “methyl trap” and homocysteine will accumulate
What are the functions of Ca2+?
In bone and as a messenger
What are the functions of P?
Bone, phospholipids and as a messenger
What is refeeding syndrome?
Starved people given glucose and saline will see stimulation of rapid glycogen synthesis, which depletes plasma phosphorus concentration
What is the function of iron?
On heme to bind O2
What transports Fe?
Transferrin
What stores Fe?
Ferritin
Hemosiderin in the liver
What is the function of ceruloplasmin?
Oxidzes ferrous iron to ferric iron for storage
What is caused by Fe deficiency?
Microcytic, hypochromic anemia
What is the function of Zn?
Zinc serves in the Zn finger structures of proteins
What can occur with Zn deficiency?
Anemia, hypogonadism and “dwarfism”; reversed on feeding of meat products
What is the function of iodine?
Essential component of thyroxine (tetraiodothyronine [T4]) & triiodothyronine (T3); essential for proper growth & development
What can occur with iodine deficiency?
Endemic goiter
What is the function of Cu?
It is a constituent of many proteins & enzymes, typically in oxidative capacity; most circulating Cu bound to ceruloplasmin
What are some diseases of Cu deficiency?
Menke’s disease – fatal X-linked disorder, mutation in ATP7A gene results in maldistribution of Cu; characterized by mental retardation; depigmented hair; low serum, brain & liver Cu but elevated in intestinal mucosa, muscle & kidneys – results in faulty connective tissue formation, death often by 3 years
