Fat-Soluble Vitamins:
A, D, E, K
Water-soluble Vitamins
B-complex:
- B1: Thiamin
- B2: Riboflavin
- Niacin
- Pantothenic acid
- B6: Pyridoxine
- Folate
- B12
- Biotin
- C: Ascorbic acid
Characteristics of vitamins
- Complex organic substance
- Required in only very small amount
- Essential (exception of Vit C)
- Function as “catalysts/coenzymes”
- Their removal from diet produces known deficiency disease
Characteristics of Fat-soluble vitamins:
Vit A+D: Stored well in liver (excessive intake is possible, liver toxicity)
Characteristics of Water-soluble vitamins
-do serve as coenzymes
- often considered “non-toxic”
- not stored (except B12)
- excess is excreted in urine
Function of water-soluble vitamins: Thiamin
required as a coenzyme in energy production, especially from carbohydrate
: as part 2 coenzyme: TPD + TDP
Thiamin Deficiency: ‘BeriBeri’
- Still occurring where refined grains (rice) eaten (Philippines)
- western countries: alcoholism
1. B1 is a coenzyme that breaks down alcohol
2. reduced absorption of B1
3. Tend to suffer from a poor diet
Symptoms of thiamin deficiency: ‘Beriberi”
- muscle weakness
- nerve (neurological) changes: coordination (arms and legs)
- Tingling, numbness
- depression
- death
Riboflavin (B2) function
Part of 2 coenzymes: FAD + FMN
- involved in processes where glucose and fatty acids
Riboflavin (B2) Deficiency
super unlikely “Angular cheilitis”
- Dry/cracking at corners of mouth
Niacin (Nicotinic Acid) function
Part of 2 enzymes (NAD + NADP: Central role in obtaining out kcal from fat, carbs, and protein)
Niacin Deficiency: “Pellagra”
-Weakness
- 3Ds of Pellagra: Dermatitis, Diarrhea, Dementia, (Death)
Niacin from Tryptophan:
1 Niacin equivalent= 1mg niacin=60mg Tryptophan
symptoms of B6 deficiency
- Anemia
- convulsions, neurological symptoms (seizures)
RDA for Vitamin C
75mg/day (women)
90mg/day men
Function(s) of vitamin C
reducing agent (donate electrons)
antioxidant
Vitamin C deficiency
Scurvy
symptoms;
- weakening of collogen in whole body and reopening of previously closed wounds
- arterial breakdown
-depression and fatigue
what circumstances require the human body to require more vitamin C>
-stress
-oral contraceptives
-smokers
cobalamin- vitamin B12
functions as coenzyme in reactions that transfer methyl (CH3) groups from 1 biomolecule to another
food sources of B12
ONLY in foods of animal origin and supplements
Vitamin B12 deficiency
- Neurological disorders
- megaloblastic anemia
what is ‘Pernicious Anemia’?
-not a dietary lack of B12
- clinically “looks” like megaloblastic Anemia
- lack of intrinsic factor
folic acid (folate) and Neutral tube defects (NTDs)
spina bifida in babies
