Vitamins

Vitamin A

1048708 RDA 700-900 ugd UL 3000 ugd

1048708 chemical forms retinol β-carotene (can be

converted to Vit A but need 6x amount)

1048708 food sources liver milk (fortified) vegetables (β-

carotene)

1048708 status determined by blood retinol concentration

1048708 lower levels indicate lower stores

1048708 primarily liver storage

3

Functions (essential for)

1048708 1 vision

2 epithelial tissue

3 growth of bone

4 reproduction

1048708 Deficiency is prevalent in developing countries

1048708 blindness sickness (1048708 immune function) death

1048708 provide Vit A supplementation develop rice with higher Vit A

4

1048708 Overdose (chronic 4x acute 100xRDA)

1048708 headaches edema fatigue anorexia skin disorders

1048708 Retinoic acid as a drug directly applied to the skin results in rapid turnover of skin cells

1048708 Retin-A acne Renova antiwrinkle

1048708 highly toxic serious birth defects if taken during pregnancy

1048708 supplementing Vit A does not help acne

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β-carotene

1048708 Vitamin A precursor

1048708 Plant sources brightly coloured eg deep orange

dark green

1048708 effective antioxidant

1048708 may reduce risk of chronic diseases

1048708atherosclerosis

1048708cancers

1048708macular degeneration (blindness in elderly)

6

chemical name cholecalciferol

1048708 function regulation of calcium and phosphorus including bone formation and maintenance

1048708 status by blood concentration

1048708 deficiency rickets and osteomalacia (bone disease in children and adults respectively)

1048708 very toxic calcium deposits in heart amp kidneys

1048708death UL 50 ugd (10x RDA)

1048708 Enjoying a resurgence in interest especially as rickets is making a comeback

7

Vitamin D 5 ugd AI

1048708 Food sources liver eggs butter fish fortified milk and margarine

1048708 Sunlight UV radiation converts precursor molecule (cholesterol backbone) in skin

1048708 duration specific to race facial area for 15 min 3-7 xweek

10487083 h for dark-skinned

1048708 Manitoba latitude April to Oct use liver stores in winter

1048708 risk of skin cancer not Vit D toxicity

8

Chemical name tocopherol

1048708 Function antioxidant in cell membranes integrity of cells (lung RBC WBC) exposed to high oxygen concentrations

1048708 Status blood concentrations and breakability of RBC

9

Deficiency is rare

1048708 hemolytic anemia (premature infants)

1048708 weakness impaired reflexes (muscle amp nerve function)

1048708 fat absorption and storage problems

1048708 Toxicity is rare

1048708 Latest evidence is that is does not protect against heart disease

10

Vitamin E 15 mgd RDA

1048708 Food sources

1048708 plant foods eg grains

1048708 associated with linoleic content in vegetable oils

11

Vitamin K

1048708 Danish ldquokoagulationrdquo

1048708 Function blood clotting amp bone synthesis

1048708 Status by blood clotting test

1048708 dicumarol (drug) interferes with Vit K and

blood clotting test before surgery

1048708 Deficiency rare except newborns (easy bruising)

1048708 Toxic in excess (infants pregnancy) sold as single

vitamin by prescription

12

Vitamin K 90-120 ugd AI

1048708 Bacterial production in colon (~12 required)

1048708 affected by absorption problemsillness

1048708 antibiotics decrease production

1048708 Food sources (~12 required)

1048708 green leafy vegetables cabbage family

1048708 liver eggs milk

1048708 beans

13

Summary

Fat soluble vitamins

1048708 dissolve in lipid

1048708 require bile for absorption

1048708 stored in tissues eg liver adipose

1048708 may be toxic in excess

1048708caution with supplements

14

The B Vitamins (8)

1048708 Involved in energy metabolism

1048708 thiamin riboflavin niacin

1048708 biotin pantothenic acid

1048708 B6 folate B12 (amp red blood cell function)

15

Thiamin

1048708 Deficiency disease beriberi (polished rice)

1048708 depression weakness polyneuropathy

1048708 Functions

1048708 coenzyme (TPP) reactions involving CO2

1048708releasing energy from glucose amp fat

1048708 synthesis of acetylcholine (neurotransmitter)

1048708 synthesis of ribose (RNA component)

1048708 alcohol metabolism

16

Thiamin Beriberi

17

Riboflavin

1048708 Deficiency disease ariboflavinosis

1048708 2 months to evolve may exist with other B vitamin deficiencies (same food sources)

1048708 affects skin eyes mouth tongue

1048708 Functions

1048708 coenzyme (FMN FAD) in energy production releasing energy from glucose and fat

18

Niacin

1048708 Deficiency disease pellagra (4 Drsquos)

1048708 dermatitis diarrhea dementia death

1048708 diet cornmeal salted fat pork molasses

1048708 Functions

1048708 coenzyme (NAD NADP) in energy production

releasing energy from glucose and fat

1048708 synthesis of fatty acids amp steroids (cholesterol)

19

Thiamin Riboflavin Niacin

1048708 DRIs based on energy requirements

1048708 higher in growth pregnancy lactation high physical activity athletes

1048708 NE (niacin equivalents) niacin (1 mg) synthesized from tryptophan (60 mg)

1048708priority proteinneurotransmitter function

1048708 Supplements do not stimulate energy production unless one is deficient in one of these vitamins

20

Thiamin Riboflavin Niacin

1048708 Food sources (also sources of tryptophan)

1048708 enriched (added back to the natural level) amp whole grains cereals and baked products

1048708 legumes

1048708 leafy green vegetables mushrooms

1048708 meat fish eggs

1048708 milk amp milk products (especially riboflavin)

1048708 corn tortillas lime water increases bioavailability of niacin from corn

21

Thiamin Riboflavin Niacin

1048708 Toxicity of thiamin amp riboflavin is rare

1048708 Niacin is used as a drug for lowering blood cholesterol and treating schizophrenia

1048708 Niacin toxcity (supplement linked)

1048708flushing of skin red skin rash

1048708tingling sensation in handsfeet

1048708stomach pain nausea diarrhea

1048708 Body adapts to high doses but monitor for liver damage

22

Biotin

1048708 Deficiency feeding raw egg white protein (contains avidin) to rats resulted in hair loss dermatitis and neuromuscular dysfunction

1048708 avidin binds biotin amp denatured by cooking

1048708 rare in humans (malnutrition)

1048708 Function cofactor in

1048708 energy production from glucose and fat

1048708 gluconeogenesis

1048708 amino acid metabolism

23

Biotin 30 ugd AI

1048708 Produced by bacteria in colon

1048708 Food sources widespread

1048708 No increased needs or toxicity described

24

Pantothenic Acid

1048708 Deficiency rare general failure of body

1048708 Functions (100+ steps)

1048708 cofactor (CoA) in energy metabolism amp synthesis of fatty acids cholesterol steroid hormones neurotransmitters hemoglobin

1048708 AI 5 mgd linked to energy needs

1048708 Food sources widespread

25

Vitamin B6 (Pyridoxine)

1048708 Deficiency weakness irritability convulsions microcytic anemia greasy dermatitis

1048708 eg heating infant formula amp destruction of B6

1048708 Functions (coenzyme = PLP)

1048708 NB amino acid amp protein metabolism and neurotransmitter synthesis

1048708 50+ steps in energy metabolism

1048708 synthesis of hemoglobin

1048708 synthesis of niacin from tryptophan

26

Vitamin B6

1048708 RDA 13 mgd linked to protein intake

1048708 Food sources green leafy vegetables meat fish poultry legumes fruits whole grains

1048708 Toxicity from supplements gt1000 mgd numbness due to nerve damage reversed when quit supplements

1048708 Supplements may be some benefit in carpal tunnel syndrome

27

Folate (Folic Acid)

1048708 Deficiency affects rapidly dividing cells

1048708 macrocytic anemia

1048708 nerve function amp neural tube defects (NTDs)

104870811000 births 2nd most common birth defect

1048708At risk

1048708 pregnant women premature infants

1048708 elderly (folate interacts with medications)

1048708 alcoholics (1048708 folate absorption)

1048708smoking (folate inactivation in lungs)

28

Folate

1048708 Functions

1048708 coenzyme for synthesis of DNA RNA amino acids

1048708NB Growth early embryonic life and tissue turnover (intestine skin RBC)

1048708 Low folate status may contribute to hyperhomocyteinemia a risk factor for cardiovascular disease

29

Folate (ldquofoliagerdquo)

1048708 RDA 400 ugday

1048708 additional 200 ugday during pregnancy

1048708 recommendations for folate supplementation before pregnancy

1048708 Food sources leafy green vegetables asparagus fruit legumes seeds liver

1048708 Folate fortification of flour

1048708 Potential problem masking Vitamin B12 deficiency

30

Vitamin B12 (cobalamin)

1048708 Deficiency pernicious anemia (macrocytic) neuromuscular dysfunction

1048708 Functions

1048708 myelin in nerve fibers (nerve transmission)

1048708 coenzymes in energy amp amino acid metabolism

1048708 B12 binds intrinsic factor (IF) in stomach amp facilitates absorption in small intestine

1048708 B12 absorption in elderly

31

Vitamin B12 (RDA 24 ugday)

1048708 If no intrinsic factor injections of B12

1048708 Food sources animal origin fermented products fungi algae fortified soymilk

1048708 Risk of deficiency breastfed infants of vegan mothers (Adults have body stores for 5 yrs)

1048708 Folate supplementation masks B12 deficiency ie improves anemia but progressive malfunctioning of nerves and muscles creeping paralysis

32

Vitamin C (Ascorbic Acid)

1048708 Deficiency scurvy

1048708 Function

1048708 collagenconnective tissue (bones teeth skin

tendons)

1048708 antioxidant protection

1048708 promotes iron absorption

1048708 enhances immune function

1048708 synthesis of thyroxine (regulates basal metabolic rate and body temperature)

33

Scurvy symptoms gums and skin

34

Vitamin C

1048708 RDA 75-90 mgd (old RNI 20-40 mgday)

1048708 additional 35 mgd for smokers (and passive smoke)

1048708 Food sources citrus vegetables

1048708 Low toxicity but problems if gt2 gday eg Altered insulin response to carbohydrate

1048708 Vit C supplements amp common cold Placebo effect

35

Summary

1048708 Water soluble vitamins

1048708 dissolve in water

1048708 are easily absorbed amp excreted

1048708 are not stored extensively in tissues

1048708 seldom reach toxic levels

36

Controversy

1048708 Dietary Antioxidants Food or Pills

1048708 Epidemiological studies show protective effects of food sources (diets high in fruits and vegetables)

1048708 Foods contain many protective chemicals in addition to vitamins eg phytochemicals

1048708 The theory of free radicals antioxidants and disease

37

Research on supplementation

1048708 Positive outcome (last year-now debateable)

supplementation of Vitamin E may provide additional antioxidant protection and decrease chronic disease risk eg heart disease or may increase mortality in some susceptible

Individuals

1048708 Negative outcome supplementation of β-carotene increased incidence of lung cancer in smokers

rarrresearch study stopped

38