Nutrition II Flashcards
Micronutrient types
- Vitamins
* Minerals
Vitamins definition and role
- Do not serve as source of energy
- Participate in various essential chemical processes
- Lack -> overt symptoms of deficiency
Vitamin types
Fat soluble: A, D, E, K
Water soluble: B-vitamins, C
Fat-soluble vitamins features
- Absorbed like fat into lymphatic system
- Stored in larger quantities in fatty tissue
- Less vulnerable to cooking losses
Water-soluble vitamins features
- Absorbed into bloodstream
- Stored in small amounts
- Vulnerable to cooking losses
Vitamin A roles
- Promoting vision
- Participating in protein synthesis and cell differentiation
- Supporting reproduction and growth
- Role in immunity
Vitamin A types
- Provitamin A carotenoids
* Preformed vitamin A
Vitamin A sources
Provitamin A carotenoids: in plant foods • leafy vegetables • carrots • apricots • red palm oil
Preformed vitamin A: in animal foods • chicken liver • cod liver oil • whole egg • fortified milk
Vitamin D role
- Maintain serum levels of calcium and phosphate
* Maintenance of skeletal integrity
Vitamin D sources
- Fortified milk
- Cereal
- Fatty fish (mackerel, salmon, sardines)
- Egg yolks
Vitamin E roles
Acts as antioxidant to prevent free radical damage
Vitamin E sources
- Vegetable oils
- Unprocessed cereals and nuts
- Meats
Vitamin K roles
- Carboxylation of clotting factors
- Bone formation
- Regulation of multiple enzymes systems
Vitamin K sources
- Green leafy vegetables
* Liver cheeses
Vitamin A deficiency symptoms
- Night blindness
- Corneal drying (xerosis)
- Triangular gray spots (Bitot’s spots)
- Softening of cornea (karatomalacia)
- Corneal degeneration
- Blindness (xerophthalmia)
Vitamin D deficiency symptoms
- Rickets
* Osteomalacia
Vitamin E deficiency symptoms
Peripheral neuropathy (degeneration of large caliber axons in sensory neurons)
Vitamin K deficiency symptoms
- Haemorrhages
- Increased bruising
- Increased hip fractures incidence
Vitamin C roles
- Hydroxylation reactions of collagen and carnitine synthesis (helps to keep skin healthy)
- Improves iron absorption
- Antioxidant
Vitamin C sources
- Citrus fruits
- Green vegetables
- Tomatoes
- Organ meats
Vitamin B1 name
Thiamine
Vitamin B1 roles
- Coenzyme (thiamin diphosphate TDP) for energy transformation
- Coenzyme for synthesis of pentoses
- Involved in neurotransmission and nerve conduction
Vitamin B1 sources
- Lean pork
- Beef
- Liver
- Yeast
- Unpolished rice
Vitamin B2 name
Riboflavin
Vitamin B2 roles
• Precursor of FAD oxidation-reduction reactions
Vitamin B2 sources
- Milk
- Organ meats
- Grains
- Broccoli
Vitamin B3 name
Niacin
Vitamin B3 roles
• Precursor of NAD oxidation-reduction reactions
Vitamin B3 sources
- Meat
- Legumes
- Milk
- Eggs
- Yeast
Vitamin B5 name
Pantothenic acid
Vitamin B5 roles
• As Coenzyme A acyl group transfer reactions
Vitamin B5 sources
- Meat
- Grains
- Liver
- Yeast
- Egg yolk
- Legumes
- Some produced by GI bacteria