NEW guidelines issued by the Institute of Medicine released 11/30/10
Raised RDA for Vitamin D:
from 200/400 to 600 IUs/day for people aged 1-70
800IUs for elders over 70
they specifically say that there is no extra benefit for bones of taking more
they don't address the other reasons that people may choose to take more
Raised RDA for Calcium to
700mg/day for children 1-3
1,000mg for kids 4-8
1,300mg for adolescents 9-18
1,000mg adults 19-50 and men to age 71
women at 51 and up, men 71 and up need 1,200 mg
DRI = daily reference intake
evidence based
the problem is that not all evidence is created equal
there's a lot that hasn't been effectively studied
conclusions based on studies that fail to show clear benefits of higher doses, and studies that suggest harm
vit D: 2000IU/day seems harmless but we have no longterm studies
when evidence is in short supply we turn to models/theories to plug the gaps
esp: transcultural comparisons and paleoanthropology.
transcultural comparisons: see variations in health associated with variations in nutrition
support the IOM's conclusion about calcium
most pops consume less than in the U.S., but have fewer cases of osteoporosis
mbdt: more weight-bearing exercise, less dietary protein/acid, more sun exposure-->thus higher D
humans with more sun exposure near equator have higher D levels than house-bound, temperate climate pop
all humans were originally dark-skinned
genetic mutation-->pale (white) skin-->spread in pops away from the equator dt survival advantage
of making more vitamin D
Calcium supp may make sense
supp for adolescent girls and adult women may make sense
for PMS
SOURCES
http://www.webmd.com/diet/news/20101129/guidelines-increase-vitamin-d
http://www.huffingtonpost.com/david-katz-md/vitamind--andcalcium-shouldwe--becautious_b_789842.html
https://www.consumerlab.com/reviews/Vitamin_D_Supplements/Vitamin_D/
http://www.rttnews.com/ArticleView.aspx?Id=1493866