liveonearth: (Default)
liveonearth ([personal profile] liveonearth) wrote2010-12-02 09:38 am

IOM changes RDA for Vitamin D and Calcium

The Institute of Medicine is trying to catch up with modern medical practice and has bumped up the recommended daily allowances of Vitamin D and Calcium in response to overwhelming evidence that most North Americans are deficient.

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

[identity profile] rick-day.livejournal.com 2010-12-03 06:03 am (UTC)(link)
its not enough. Should be 4000 IUs/day

[identity profile] liveonearth.livejournal.com 2010-12-03 06:19 am (UTC)(link)
Yep. Or maybe those who are dosing 100,000 IUs once a week are on the right track. We don't have any really good info about what sustained supplementation will do, but we do know what longterm deficiency does. 4,000 is probably a good bet for indoor dwelling North Americans.