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OCT 2017 FOOD FOCUSTHAILAND
STRATEGIC
R & D
say people should go higher, to about 30 ng/mL to get the full health
benefits of vitaminD.
HowMuchVitaminDDoYouNeed?
The recommended dietary allowance for vitamin D is 600 IU
(international units) per day for adults up to age 70. People aged 71
and older should aim for 800 IU from their diet. Some researchers
recommendmuchhigher doses of vitaminD, but toomuch vitaminD
canhurtyou.Above4,000 IUperday, the risk forharm rises,according
to the Instituteof Medicine.
Daily “D” for BreastfeedingBabies
Breast milk is best, but it doesn’t have much vitamin D. Breastfed
babiesneed400 IUofvitaminDuntil they’reweaned to fortified formula
andcandrinkat least one liter (about 4¼cups) everyday. Startingat
age 1, babies drinking fortified milk no longer need a vitamin D
supplement.Becareful not togive toomuchvitaminD tobabies.High
doses can causenausea, vomiting, loss of appetite, excessive thirst,
muscle aches, ormore serious symptoms.
VitaminD forOlder Children
Mostchildrenandadolescentsdon’tgetenoughvitaminD fromdrinking
milk. They should have a supplement with 400 IU to 600 IU. That
amount isoften included inchewablemultivitamins.Childrenwithsome
chronic diseases such as cystic fibrosismay be at increased risk for
vitaminDdeficiency.Talk toyourchild’sdoctorabout theneed forextra
vitaminD.
HowMuch IsTooMuchVitaminD?
Some researchers suggest taking farmore vitaminD than the600 IU
daily guideline for healthy adults. But toomuch be dangerous. Very
high doses of vitamin D can raise your blood calcium level, causing
damage tobloodvessels,heart,andkidneys.The InstituteofMedicine
sets theupper tolerable limitat4,000 IUof vitaminDperday.Youcan’t
get toomuch vitaminD from the sun. Your body simply stopsmaking
more. But sunexposurewithout sunscreen can raise your riskof skin
cancer.
VitaminD andMultipleSclerosis
Multiple sclerosis (MS) is more common far away from the sunny
equator.For years, expertssuspecteda linkbetweensunlight, vitamin
D levels,and thisautoimmunedisorder thatdamages thenerves.One
newer cluecomes fromastudyof a raregenedefect that leads to low
levels of vitamin D – and a higher risk of MS. Despite these links,
there’snotenoughevidence to recommendvitaminD for theprevention
or treatment of MS.
VitaminD andDiabetes
Some studies have shown a link between a low vitamin D level and
type 1 and type 2 diabetes . So, can boosting your vitamin D levels
help ward off the disease? There’s not enough proof for doctors to
recommend taking thissupplement toprevent diabetes. Excessbody
fat may play a role in type 2diabetes and low levels of vitaminD.
VitaminD andWeight Loss
Studieshave shown that peoplewhoareobeseoftenhave lowblood
levels of vitaminD. Body fat traps vitaminD, making it less available
to the body. It’s not clear whether obesity itself causes a low vitamin
D level or if it’s the other way around. But one small study of dieters
suggests that adding vitamin D to a calorie-restricted diet may help
overweight peoplewith low vitaminD levels loseweight more easily.
VitaminD andHeart Disease
Low levels of vitamin D have been linked to a greater risk of heart
attack, stroke, andheart disease. Still, it’s not clear whether boosting
vitaminDwill reduce heart risks and howmuch vitaminD is needed.
Very high levels of vitamin D in the blood can actually harm blood
vessels and the heart by increasing the amount of calcium in the
bloodstream.
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ง/References
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Health.”
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Bertone-JohnsonER. Nutritional Review. August 2009.
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Diabetes Forecast, “TheRoleof VitaminD inType2Diabetes,” December 2011.
FoodandDrugAdministration: “Infant OverdoseRiskWithLiquidVitaminD.”
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