Micronutrients: Vitamins, Minerals & Nutritional Deficiencies Pt 1

Question 1

Vitamins

2 types

Answer 1

• Vitamins are micronutrients
– Our bodies require relatively small amounts of vitamins to support normal health and body functions
• Are organic compounds and DO NOT contain energy
– Essential for intermediary energy metabolism (catabolizing macronutrients to produce ATP)
– Also play important roles in building and maintaining healthy bone, muscle and blood
– Support our immune system
– Ensure healthy vision

• Classified into 2 types
– Fat soluble (A, D, E & K)
– Water Soluble (C & B-vitamins)

we dont generate energy from them

Question 2

fat sol vs water sol vitamins

Answer 2

• Fat soluble vitamins
– Stored in adipose tissue, difficult to be deficient, adverse effects common
– Toxicity can occur from consuming excess amounts, which accumulate in the body

• Water soluble vitamins
– Not store to any extent in the human body
– Excess excreted in the urine
– Toxicity generally only occurs via vitamin supplementation
- difficult to get too much from diet

Question 3

The B-Vitamins
primary role
water sol

Answer 3

• The primary role of B-vitamins is to act as coenzymes
• A coenzyme is a molecule that combines with
an enzyme to activate it and help it do its job
(catalyze its reaction)
enzyme action accelaerated in presence of coenzyme

we metabolize these macronutrients to make energy they are dependent on numerous cofactors

Many of the coenzymes are essential for various metabolic functions, however, this is only a small sample of the thousands of roles B-vitamins have.

Question 4

Thiamin (Vitamin B1)

role

• Food sources with high amounts of thiamine include
– Whole-grain products
– Pork products
– Some green vegetables (peas, asparagus, okra)
– Low in processed foods

Answer 4

• Thiamin is part of the coenzyme thiamin pyrophosphate (TPP)
– Plays a critical role in the metabolism of glucose and branched chain amino acids
– Also plays a role in producing DNA/RNA and in the synthesis of neurotransmitters

Question 5

Thiamin (Vitamin B1)

deficiency causes?
AE

Answer 5

• Deficiency for thiamin causes beriberi: inflamm of nerves that can lead to HF, fatigue, msucle weakness, reduce cog fxn
- ppl were eating grain but not whole grain can cause beberi

• No known adverse effects from consuming excess
thiamin
– Thus no tolerable UL has been established

Question 6

Riboflavin (Vitamin B2)

role - cause water to change yellow

Food sources with high amounts of riboflavin include
– Dairy products (milk)
– Meat products (poultry, fish, eggs)
– Some green vegetables (broccoli, asparagus, spinach)
– Usually low in whole grains

Answer 6

Riboflavin is an important component of the coenzyme
flavin mononucleotide (FMN) & flavin adenine
dinucleotide (FAD)
– Are very important in the regulation of metabolism of
carbohydrates/fat, Krebs cycle
make energy from burning sugar of fat
– Also part of the antioxidant enzyme glutathione peroxidase

Question 7

Riboflavin (Vitamin B2)

deficiency causes?
AE

Answer 7

• Deficiency for riboflavin causes ariboflavinosis
• Because riboflavin is so important towards energy
metabolism, deficiency can produce symptoms such as
fatigue and muscle weakness
– More advanced deficiency can result in irritation, inflammation, and ulceration of body tissues
– Severe deficiency can impair metabolism of vitamin B6 and niacin

• No known adverse effects from consuming excess
riboflavin
– Thus no tolerable UL has been established

Question 8

Niacin (Nicotinamide & Nicotinic Acid)
role

Food sources with high amounts of niacin include
– Meat, poultry, fish
– Whole grain and enriched bread products
– Coffee and some teas

Answer 8

• There are 2 forms of niacin, nicotinamide & nicotinic acid
– Are converted into active coenzymes (NAD & NADP) that assist in the metabolism of carbohydrates and fatty acids
– Also play important roles in DNA replication, repair, and cell differentiation
elongate fatty acids

NAD – nicotinamide adenine dinucleotide
NADP – nicotinamide adenine dinucleotide phosphate

Question 9

Niacin (Nicotinamide & Nicotinic Acid)

deficiency causes?
AE

Answer 9

• Deficiency for niacin causes pellagra (angry skin)
– Characterized by dermatitis, diarrhea, dementia & death (4D)

• Excess niacin via supplements can cause
– *Flushing
– *Itch
– Liver damage
– Glucose intolerance
– Blurred vision & edema of the eyes
bottom 4 are large doses for long periods

whole grain

Question 10

Vitamin B6 (Pyridoxine)
role

Food sources with high amounts of vitamin B6 include
– Meat products, poultry, fish, eggs
– Dairy products
– Whole grain cereals

Answer 10

• Vitamin B6 refers to 6-related compounds
– Pyridoxine, pyridoxal, pyridoxamine, & their respective phosphate forms

• Vitamin B6 influences many important functions
– Amino acid metabolism (transamination)
– Neurotransmitter synthesis (glutamate)
– Carbohydrate metabolism (glycogenolysis)
– Heme synthesis (important component of hemoglobin) –> microcytic anemia, small RBC
– Immune function: maintain lymhocyte activity
– Reductions in cardiovascular disease risk (homocysteine), not enough you can’t break down homocysteine

Question 11

Vitamin B6 (Pyridoxine)

deficiency causes? (5)
AE

Answer 11

• Deficiency for vitamin B6 may result in
– *Anemia
– Convulsions
– Depression
– Skin inflammation
– Increased risk for cardiovascular disease

• Excess vitamin B6 via supplements can cause –
Nerve damage
– Skin lesions
– *Sensory neuropathy (numb in face, neck, hands feet, difficulty manipulating objects)

sensitive to both heat and light so it’s easy it’s one of the certain vitamins, you know when you cook food, you will lose the vitamin because you will destroy it,

Question 12

Vitamin B12 (Cobalamin)
role

• Food sources with high amounts of vitamin B12 include
NEED TO KNOW THIS

Answer 12

• Vitamin B12 plays important roles in the following
– Amino acid metabolism
– Fatty acid metabolism
– Maintenance of the myelin sheath that coats nerve fibres
- dna synth
– Essential for formation of healthy red blood cells, leads to macrocytic anemia with large RBC and poor o2 carrying capacity

– Meat products, poultry, fish & eggs
– Fortified dairy products
– *Vegans need to consume foods fortified in vitamin B12
ONLY MEAT PDTS or fortified pts

Question 13

Vitamin B12 (Cobalamin)

deficiency causes?
AE

Answer 13

• Deficiency for vitamin B12 causes *pernicious anemia
– Feeling of weakness and exhaustion

• Vitamin B12 deficiency can be due to low consumption (vegans) or atrophic gastritis (not enough stomach acid), and symptoms include
– Pale skin
– Loss of ability to perform coordinated movements and maintain body position
– Irritability, confusion, depression and dementia

• There are no known adverse effects arising from
consuming excess amounts of vitamin B12

Intrinsic factor repsonsible for binding B12 and help absorb it

Question 14

Pantothenic Acid
role

Food sources with high amounts of vitamin B12 include
– Chicken, beef, egg yolks, potatoes, oat cereals

Answer 14

• Essential for fatty acid metabolism (AI: 5 mg/day in
adults)
– metabolized into 2 major coenzymes: precursor to
Coenzyme A (CoA) and acyl carrier protein
– Required for synthesizing cholesterol, steroids, and
detoxification of drugs

Question 15

Pantothenic Acid
deficiency causes?
AE

Answer 15

No adverse effects from excess amounts

• Deficiencies are very rare

Question 16

Biotin

• Biotin content has been determined for very few foods

Answer 16

Essential for fatty acid synthesis and gluconeogenesis
through actions on fatty acid, carbohydrate, and protein
metabolism
– Co-factor for various carboxylase enzymes
enlongate fatty acids

Question 17

Biotin
deficiency
AE

Answer 17

Deficiency is rare but can be seen with consumption of
raw egg whites over long periods of time
– Due to avidin protein which binds biotin and prevents absorption from GI tract

Question 18

Choline
role

Widespread in many food sources
– Milk
– Liver
– Peanuts

Answer 18

• Not a vitamin but often grouped with other B-vitamins
– Plays important roles in metabolism
• Some important roles choline participates in include;
– Cell signaling (lysophosphatidylcholine)
– Neurotransmitter (acetylcholine)
– Lipoprotein synthesis & bile formation (phosphatidylcholine)
– Membrane composition (phosphatidylcholine)

Question 19

Folate
role
deifiency

Found in many green leafy vegetables
– Called folate due to its abundance in foliage

Answer 19

• Enzymatic reactions requiring folate are important for 1- carbon metabolism
– Adding 1-carbon units to other organic compounds
• Plays important roles in nucleotide synthesis, amino
acid metabolism, and RBC synth

*anemia and *neural tube defects (rec women take folate supplement early during fetus development)

Question 20

Antioxidant Vitamins

which ones>

Answer 20

• Antioxidants are compounds that protect cells
from damage caused by oxidation ( lose that electron)
– Antioxidant vitamins include vitamins E, C & A

The substance that gains it will then have an unbearable electron become a free radical like super oxide, which is highly reactive and can lead to a number of detrimental effects, and especially in your cell membrane
antioxidants prevent that

Question 21

Vitamin E

role

Answer 21

• Vitamin E is a fat soluble vitamin that primarily
functions as an antioxidant
– Donates an electron to free radicals to stabilize them and prevent them from destabilizing other important molecules
– Protects cellular membranes from being oxidized
– Protects LDL cholesterol from being oxidized
– Protects oxidation of white blood cells (helps immunity and defense against disease)
acts an antioxidant that can react with free radicals to stabilize them can keep membrane function intact

• 90% of vitamin E in our body is stored in adipose tissue (remainder is in cellular membranes)
• The most potent form of vitamin E found in food and
supplements is alpha-tocopherol

Question 22

Vitamin E
deficiency
AE

Answer 22

• Vitamin E deficiencies are uncommon (stored in fat)
– Deficiencies may occur in diseases involving malabsorption of fat (erythrocyte hemolysis and subsequent anemia)

• Vitamin E supplementation may cause
– Nausea
– Intestinal distress
– Diarrhea
– Supplementation >RDA can increase risk for prostate cancer
– Increased risk for bleeding (mild anticoagulant actions)

Question 23

Vitamin C

role

Answer 23

*extracellular and regenerate vit E

• Vitamin C is a water soluble vitamin that primarily
functions as an antioxidant
– Donates an electron to free radicals to stabilize them and prevent them from destabilizing other important molecules
– Protects cellular membranes from being oxidized
– Protects LDL cholesterol from being oxidized
– Enhances immunity (protects white blood cells from oxidative damage that takes place when fighting infection)
– *Also acts as an antioxidant by regenerated oxidized vitamin E

• Also plays a role in regulating thyroid hormone
production
• Critical to the synthesis and maintenance of collagen