Vitamin D Intake too low-S/B at least 2000 IU/day

[Guest guest]

Orthomolecular Medicine News Service, February 19, 2010

Official Recommended Intake for Vitamin D is Too Low

2,000 IU/Day or More Needed for Optimal Health

by B. Grant, Ph.D.

(OMNS, Feb 19, 2010) Vitamin D has been a natural part of man's experience

forever, and 90% of vitamin D is derived from solar ultraviolet-B (UVB)

irradiance. The health effects of vitamin D can be and have been determined

from a variety of studies including ecological, observational (case-control

and cohort), and cross-sectional studies.

Vitamin D helps both to prevent and to treat chronic diseases including

many types of cancer, cardiovascular disease (coronary heart disease, stroke,

etc.), congestive heart failure, diabetes mellitus (types 1 and 2),

osteoporosis, falls, and fractures. It is also effective against infectious

diseases including both bacteria and viral infections: bacterial vaginosis,

pneumonia, dental caries, periodontal disease, tuberculosis, sepsis/septicemia,

Epstein-Barr virus, and influenza type A such as A/H1N1 influenza. The

autoimmune diseases include asthma, type 1 diabetes mellitus, multiple

sclerosis, and perhaps rheumatoid arthritis.

Pregnancy outcomes are also adversely affected by low serum D levels. 40%

of primary Cesarean-section deliveries in the United States are linked to

low D levels (9% of births in the United States involve primary C-section),

and preeclampsia is also linked to low serum levels of D. In regards to

cancer, vitamin D helps cells fit into the organs properly or commit suicide

(apoptosis), and also reduces angiogenesis (new blood vessel growth) around

tumors and reduces metastasis. For metabolic diseases, the mechanisms

include increased insulin sensitivity and insulin production. For infectious

diseases, vitamin D induces production of cathelicidin and defensins, which

have antimicrobial and antiendotoxin activities.

Due to current lifestyles in the United States, most people do not spend

sufficient time in the sun to produce the higher serum D levels associated

with optimal health. Black-Americans are particularly vulnerable to low

levels due to their darker skin, which reduces the amount of UVB that reaches

the 7-dehydrocholesterol in the lower epidermis to produce previtamin D.

Black-Americans have a 25% higher mortality rate than White-Americans, and

this difference may be explained in terms of lower serum 25(OH)D levels. Solar

UVB is an excellent source of vitamin D during about half of the year. The

way to take advantage of the sun as a source of vitamin D is to expose as

much of the body as possible without sunscreen near solar noon, the time

when one's shadow is shorter than one's height, for 10-30 minutes depending

on skin pigmentation, being careful not to turn pink or red or burn. (

_http://www.doctoryourself.com/holick.html_

(http://www.cihfimediaservices.org/12all/lt/t_go.php?i=54 & e=MjYyMjM= & l=-http--ww\

w.doctoryourself.com/holick.html)

)

Supplements represent an efficient way to obtain sufficient vitamin D.

African-Americans should consider taking 3000 International Units (IU) per day

while White-Americans should consider taking 2000 IU/day. The current

dietary guideline, approximately 400 IU/day, was based on the amount of vitamin

D in a spoonful of cod liver oil, which prevented rickets.

There are few adverse effects of vitamin D. With whole-body exposure to

the sun, one can make at least 10,000 IU/day in a short time. Adverse effects

such as hypercalcemia have been found in general only for 20,000-40,000

IU/day for very long periods. However, those with certain diseases such as

adenoma of the parathyroid gland, granulomatous diseases, lymphoma,

sarcoidosis, and tuberculosis, should limit their vitamin D intake or

production due

to the fact that the body's innate immune system produces too much

1,25-dihydroxyvitamin D in the serum, which can raise serum calcium levels too

high.

Several studies have examined how much mortality rates and economic

burdens of disease could be lowered if the population had more vitamin D. These

studies were for Western Europe, Canada, the Netherlands, and the United

States. They generally found that mortality rates could be reduced by about

15%.

During pregnancy and lactation, women should be taking about 6000 IU/day.

The current US " Adequate Intake " recommendation is a mere 200 IU/day. Bruce

W. Hollis and Carol L. Wagner, Medical University of South Carolina,

recently completed a randomized controlled trial vitamin D supplementation for

pregnant and nursing women and found that even 2000 IU/day was inadequate,

and that there were no adverse effects with 6000 IU/day.

For the text of a Vitamin D Scientists' Call to Action, please go to

_http://www.grassrootshealth.net_

(http://www.cihfimediaservices.org/12all/lt/t_go.php?i=54 & e=MjYyMjM= & l=-http--ww\

w.grassrootshealth.net) .

[ B. Grant earned his PhD in physics at UC Berkeley. For 15 years

he was a physicist at NASA Langley Research Center's Atmospheric Sciences

Division. He has authored or coauthored over 180 papers in peer reviewed

journals. Since he began his work on UVB/vitamin D and cancer in 2000, the list

of vitamin D-sensitive cancers has grown from 5 to at least 16. His paper

in Cancer in 2002 identified 10 additional vitamin D-sensitive cancers. Dr.

Grant directs the Sunlight, Nutrition, and Health Research Center (SUNARC)

_http://www.sunarc.org_

(