Chapter 10: Nutrients for energy metabolism Flashcards
Structure of Vitamins
organic individual units
Structure or minerals
inorganic individual units
function of vitamins and minerals
Do not yield energy; assists enzymes to release energy, vitamins can be broken down, minerals cannot
Food contents of vitamins
micrograms (ug) to milligrams (mg)
Food contents of minerals
micrograms (ug) to grams (g)
The bioavailability of vitamins and minerals
influenced by the amount in food, amount absorbed and used by the body
Factors that influence biodiversity
-Efficiency of digestion, time of transit
-nutrient status
-food preparation method
- source of nutrient
- other foods present, vitamin C enhances iron absorption and calcium inhibits it
Precursors
Some vitamins are present in a precursor form and activated inside the body
Chemical nature
some vitamins can be destroyed by light, heat or oxidation, minerals cannot
Water Soluble vitamins
Thiamin
riboflavin
niacin
biotin
pamtothenec acid
vitamin B6 and 12
folate
Vitamin C
Fat Soluble vitamins
Vitamin A
Vitamin D
Vitamin E
Vitamin K
Major Minerals
Na
K
Cl
P
Ca
Mg
S
Trace Minerals
Sl
F
I
Cr
Mn
Fe
Zn
Cu
Coenzyme
A small organic molecule that associates closely with certain enzymes, several B vitamins form part of the coenzyme that helps get energy from carbs, fats and protein
Thiamin
Pyruvate to acetyl CoA in the TCA cycle
major role in energy metabolism
controls nerve and muscle activity
RDA 1.2 mg/d for men and 1.1 mg/day for women
Thiamin deficiency
dry Beriberi: damage to the nervous system (muscle weakness in the arms and legs)
Wet Beriberi- damage to the cardiovascular system (dilated blood vessels, strain on the heart that leads to edema
Riboflavin
coenzyme in TCA (accepts and donates 2H)
RDA: 1.3mg/day for men and 1.1 mg/ for women
deficiency symptoms include inflammation of the membranes of the mouth, skin, eyes and GI tract
No know toxicity symptoms
Niacin
TCA to ETC (NAD and NADP) RDA 16mg and 14 mg for women
Niacin deficiency
pellagra
4 Ds
- Diarrhea
- dermatitis
- Dementia
- Death
Niacin toxicity
Rare from food
niacin flush
painful tingling sensation
Biotin
Delivers a carbon to pyruvate to replenish oxaloacetate which can be a limiting compound in the TCA
AI 30 ug/day
-No RDA or UL
deficiency: skin rash, hair loss, neurological impairment produced by bacteria in GI tract
Pantothenic Acid
Part of coenzyme A
AI is 5 mg/day. Deficiency is rare and there is no UL
B6
Pyridoxal phosphate
amino acid metabolism
stored in muscles
recommendations: 1.3 mg/day
deficiency and toxicity are rare
UL is 100 mg/day
Folate
Synthesis of DNA
THF
RDA is 400 mg/day
recommended as a supplement for anyone who could become pregnant
Deficiency of folate
Neural tube = brain and spinal cord, can lead to death
mandatory fortification
Folate deficiency
GI deterioration and anemia caused by inadequate intake of impaired absorption
has some drug interactions
B12
Closely related to folate
maintain sheath on nerve cell and bone cell activity and metabolism
bone cell activity and metabolism
B12 absorption
requires HCL and IF
recommendations:2.4 ug a day
poor absorption of pernicious anemia lead to neurological symptoms exclusively in meat and nutritional yeast
what can supplements do
correct deficiencies
support inc nutrient needs
improve nutrition status
improve body defences
reduce disease risk
who needs supplements
specific nutrient deficiency
low engine intakes
vegans and older adults
lactose intolerance
medications
stages of life cycle
vit D in the winter
medical conditions
