Folate Flashcards
how are the folate requirements expressed?
As dietary folate equivalents, to take into account the different forms and their availabilities.
What is the most bioavailable form?
Synthetic folic acid (1.7x more bioavailable)
what are the folate requirements?
adults - 400ug/d
Pregnant = 600ug
lactating = 500ug/d
UL = 1mg/d
What vitamin deficiency can high doses of folate mask?
B12 deficiency symptoms can be masked.
What are 3 main sources of folate?
liver, dark leafy greens, legumes
What is the bioavailability of folate?
food folate is <50%
What causes low folate bioavailabilty?
- poly- versus mono-glutamate (easier for transport)
- trapped by plant material
- organic acids inhibit conjugase activity
- losses during preparation
what is folate conjugase?
the enzyme that converts the lower bioavail form poly-glu to mono-glu
how is short and long term folate balance determined?
Short-term = serum folate
Long-term = RBC folate* more reliable
What are the 4 effects of folate deficiency?
- megaloblastic anemia
- Cancer
- Vascular disease
- Birth defects
What can cause folate deficiency?
- poor diet
- malabsorption
- metabolic disorders, alcohol + drugs
Which enzyme in the folate cycle is affected by a SNP? And what can be the result/illness of this gene mutation?
MTHFR polymorphism
Neural tube defect where the neural tube does not close.
Which is the most common NTD?
Spina bifida
