Water Soluble Nutrients

Question 1

Characteristics/features of vitamins, are they micronutrients or macronutrients? How many kcals do vitamins provide?

Answer 1

Vitamins are micronutrients

Do not provide energy (no kcals)

Question 2

Where do water-soluble vitamins get absorbed?

Answer 2

The small intestine

Question 3

Basic function of a coenzyme

Answer 3

Coenzymes are ions or small molecules that interact with enzymes, enabling the enzymes to function

Most b vitamins function as components of coenzymes

Question 4

Water soluble vitamins can be destroyed by what during cooking/preparation?

Answer 4

Can be destroyed by exposure to heat, light, air, and alkaline substances

Question 5

Best cooking techniques to preserve water soluble vitamins

Answer 5

Steaming, stir frying, and microwaving

Question 6

Thiamin, riboflavin, niacin – common food sources and common functions

Answer 6

Functions:
Thiamin: coenzymes form participates in glycolysis and in the citric acid cycle
Riboflavin: coenzymes in citric acid cycle
Niacin (B3): acts as a coenzyme in glycolysis, citric acid cycle
*Releasing energy from energy-yielding nutrients

Food sources:
Meats
Whole, fortified, or enriched grains
Milk, cheese, beans, mushrooms, yogurt, etc..

Question 7

Which nutrient may lower the risk for neural tube defects?

Answer 7

Folate

Mandatory fortification of refined grains since 1988:
Supplies 200 ug/d
Reduce neural tube defects by 1/4

Question 8

Megaloblastic anemia may develop from ___ ?

Answer 8

Anemia: decreased oxygen carrying capacity of the blood (can be caused by many factors, iron deficiency or blood loss).

Deficiency of folate and/or Vit B12

Characterized by large, immature RBCs (red blood cells)

Question 9

Which population would be at risk for B12 deficiency?

Answer 9

Older adults:
Affects 20% of older adults
causes= atrophic gastritis, impaired synthesis or function of R-protein, proteases, or intrinsic factor

Those with malabsorptive disorders:
Complex digestion absorption of Vit B12

Long Term vegan or vegetarian diet

Infant ingestion of breast milk from Vit B12 deficient mothers

Question 10

B12 digestion, absorption, and storage is unique – know role of intrinsic factor, and for how long B12 can be stored

Answer 10

Unique:
Foods of animal origin are the only reliable source of vit B12
Only vitamin that contains a mineral (cobalt) as part of its structure

Intrinsic factor is a substance in gastric juice that enhances vitamin B-12 absorption (protein like compound produced by parietal cells in the stomach to enhance vitamin B-12 absorption)

*Liver can store enough B12 to last several years

Question 11

What water-soluble vitamin helps with the formation of collagen?

Answer 11

Vitamin C

Question 12

Releasing energy from energy-yielding nutrients

Answer 12

Thiamin (B1)

Riboflavin (B2)

Niacin (B3)

Question 13

Amino Acid Metabolism

Answer 13

Thiamin (B1)

Folate

Vitamin B12 (cobalamin)

Question 14

Neurotransmitter synthesis

Answer 14

Niacin (B3)

Vitamin B6 (pyridoxine)

Folate

Vitamin C

Question 15

Thiamin (B1): Food sources

Answer 15

Pork, tuna

whole, fortified, enriched grains

milk, cheese, yogurt

dried beans (lentils, soybeans, black, navy)

Question 16

Thiamin (B1): Function

Answer 16

Coenzyme form participates in glycolysis and in the citric acid cycle

Question 17

Thiamin (B1): Deficiencies

Answer 17

Beriberi

Symptoms: extreme weakness, paralysis, and fatigue; brain and nervous
system are especially affected because of their reliance on glucose

At risk populations:
Alcoholics
Elderly
Malabsorptive conditions

Wernicke-Korsakoff Syndrome: degenerative brain disorder associated
with deficiency of thiamin (also known as cerebral Beriberi)

• Related to alcohol abuse → decreased thiamin absorption, poor dietary intake, and increased thiamin excretion
• Affects central nervous system
• Symptoms: abnormal eye movements, staggering gait, distorted
  thought processes

Question 18

Riboflavin (B2): Food sources

Answer 18

Milk, yogurt, cheese, cottage cheese

Whole, fortified, or enriched grains

Eggs

Mushrooms

Beef liver, steak

Question 19

Riboflavin (B2): Functions

Answer 19

Coenzyme in Citric Acid Cycle

Fatty acid breakdown

Electron Transport Chain

Activates other B-vitamins

Antioxidant function by
synthesizing glutathione

Question 20

Riboflavin (B2): Deficiencies

Answer 20

Ariboflavinosis: primarily affects mouth, skin, and red blood cells

Symptoms: cracked tissue around the mouth; inflamed throat, tongue

Populations at risk:
* Alcoholics
* Malabsorptive disorders
* Poor diets

Question 21

Niacin (B3): Food sources

Answer 21

Meats (all types)

Whole, fortified, or enriched grains

Dried beans, nuts

Milk, cheese, yogurt

Coffee

Mushrooms

Salmon, Cod, Shrimp, Clams, Halibut

Question 22

Niacin (B3): Functions

Answer 22

Acts as a Coenzyme in:
* Glycolysis
* Citric Acid Cycle
* Pyruvate to Lactate
* Fatty acid synthesis
* Alcohol metabolism

Question 23

Niacin (B3): Deficiences

Answer 23

Pellagra

Symptoms:
4 D’s – diarrhea, dermatitis, dementia, death

Question 24

Niacin (B3): Toxicity

Answer 24

UL for niacin is 35 mg/day
Megadoses (>250 mg/day) are prescribed to:
* Reduce elevated LDL cholesterol levels
* Increase HDL cholesterol levels

Side effects:
* Flushing of skin, itching, painful tingling, GI tract upset, liver damage

Question 25

Vitamin B6 (pyridoxine): food sources

Answer 25

Meat (pork/beef) and poultry Fish (Halibut, Herring) Enriched, fortified cereals Seeds: sesame and sunflower Garbanzo beans White potato

Question 26

Vitamin B6: functions

Answer 26

Involved in Transamination reactions/Amino Acid Metabolism Involved in Synthesis of: Heme - forms the protein hemoglobin, a compound that contains iron Neurotransmitters – serotonin, dopamine and norepinephrine

Question 27

Vitamin B6: Toxicity

Answer 27

The UL for vitamin B‒6 is 100 mg/day Megadoses occur from supplementation Recommended to treat premenstrual syndrome (PMS) and morning sickness, however, there is not enough evidence to support this use Can cause peripheral neuropathy -- severe sensory nerve damage

Question 28

Folate (folic acid): food sources

Answer 28

*Fortified or enriched grains *Orange juice Dried beans (kidney, pinto, black, lentils) Broccoli, asparagus, artichokes, beets, avocado *Dark green leafy vegetables (mustard & turnip greens, romaine lettuce, spinach)

Question 29

Folate: functions

Answer 29

Amino acid metabolism DNA synthesis & function Red blood cell formation Neurotransmitter synthesis

Question 30

Folate: deficiences

Answer 30

Factors lead to deficiency * Low intake * Malabsorption * Increased requirements (pregnancy) * Excessive excretion * Use of certain medications Associated with elevated blood levels of homocysteine * Recognized risk factor for CVD Neural Tube Defects * Spina bifida – spinal cord or spinal fluid bulge through back *recommended all women capable of becoming pregnant consume 400micrograms of folic acid daily from supplements or fortified foods

Question 31

Vitamin B12 (cyanocobalamin):

Answer 31

Unique: Foods of animal origin are the only reliable source of vit B12 Only vitamin that contains a mineral (cobalt) as part of its structure Intrinsic factor is a substance in gastric juice that enhances vitamin B-12 absorption (protein like compound produced by parietal cells in the stomach to enhance vitamin B-12 absorption) *Liver can store enough B12 to last several years

Question 32

Vitamin B12: food sources

Answer 32

Meats (beef/pork/chicken) Seafood(salmon/tuna/shrimp/oysters/crabs/clams) Milk, cottage cheese, yogurt Eggs Fortified soymilk and cereals Food sources: naturally present only in foods of animal origin * Plants do not synthesize B12 * Synthesized by microorganisms, mainly bacteria * Animals acquire B12 from soil ingested while eating and grazing * Dietary vitamin B-12 is protein-bound

Question 33

Vitamin B12: functions

Answer 33

Coenzyme functions * 1-carbon transfer reactions * Amino acid metabolism * Metabolize some fatty acids * DNA regulation * Red blood cell formation * Nerve function by maintaining the myelin sheath * Example: Folate and Vit B12 are needed for AA conversion of homocysteine to methionine →

Question 34

Yes or no: folate and vitamin b12 work together

Answer 34

In body cells * Inactive folate is activated by the removal of the methyl group from the folate compound by inactive Vit B12 * When Vitamin B12 acquires the methyl group, it becomes activated Folate and B12 are closely linked= a vitamin B12 coenzyme is required to recycle the folate coenzyme needed for DNA synthesis, deficiencies can produce identical signs and symptoms

Question 35

Vitamin B12: deficiencies

Answer 35

Pernicious anemia: * Result of impaired B-12 absorption secondary to atrophic gastritis and lack of intrinsic factor Neurological changes Elevated plasma homocysteine Population at risk: Older adults * Affects 20% of older Americans * Causes = atrophic gastritis, impaired synthesis or function of R-protein, proteases, or intrinsic factor Those with malabsorptive disorders * Complex digestion and absorption of Vitamin B12 Long-term vegan or vegetarian diet Infant ingestion of breast milk from vitamin B-12-deficient mothers

Question 36

Vitamin C: food sources

Answer 36

Citrus fruits 100% juices (cranberry/apple/orange) Strawberries Broccoli, cauliflower, kale, brussels sprouts Green and red pepper

Question 37

Vitamin C: functions

Answer 37

Antioxidant Donates electrons to inactivate free radicals and prevents them from damaging lipids, DNA, and proteins Regenerate the active form of Vit E Collagen synthesis *does not cure the common cold

Question 38

Vit C requirements

Answer 38

Minimum requirements: 10 mg/d RDA: * 90 mg/d for adult men * 75 mg/d for adult women Increased needs: * Smokers (+35 mg/d) * Oral contraceptives

Question 39

Vitamin C: Deficiency

Answer 39

Scurvy – deficiency disease of Vitamin C First signs/symptoms appear about 20-40 days into a diet free of Vitamin C Disrupts synthesis of collagen (major fibrous protein that holds together the various structures of the body, it is very strong and elastic) Without Vitamin C → collagen is weak and fragile Symptoms: bleeding swollen gums and joints, impaired wound healing, pinpoint hemorrhages of the skin → (spots on the skin are caused by slight bleeding, Person may experience poor wound healing, all signs and symptoms of defective collagen synthesis)

Question 40

Vitamin C: toxicity

Answer 40

UL: 2000 mg/day Consequences: * Gastrointestinal effects (bloating, diarrhea) * Kidney stone formation * Excess iron absorption * False readings on medical tests Intakes >100 mg/d increase urinary excretion