New Vitamin D Evidence Report Reveals Gaps in
Knowledge and Serves as Basis for Upcoming NIH Conference on
Vitamin D and Bone Health
A new evidence report on vitamin D and bone health reviews the
current scientific evidence and identifies its strengths and weaknesses.
This report will be a valuable resource for an upcoming National
Institutes of Health conference September 5-6 that will examine
a range of scientific perspectives related to vitamin D and bone
health across the lifecycle.
"This independent, systematic review is timely because there are
mixed messages and recommendations to consumers regarding the benefits
and harms of vitamin D intake" said NIH Office of Dietary Supplements
(ODS) Director, Paul M. Coates, Ph.D. He added, "The evidence report
in combination with the conference presentations and discussions,
newly available methodological tools, and newer information on
the vitamin D status of the US population will provide an invaluable
and very timely update for the research and public health communities
of what we know and what we need to know for this key nutrient."
Researchers have long known that vitamin D had an impact on bone
health but there is uncertainty about how much vitamin D is needed
to achieve optimal bone health and whether there are differences
in the relationship of vitamin D status to bone health across age
and life stage groups. This report highlights the fact that the
largest amount of evidence for bone health benefits is in postmenopausal
women and older men (the majority over 60 years of age) taking
vitamin D supplements. This report also confirms that vitamin D
from ultraviolet-B (sunlight) exposure, fortified foods, or dietary
supplements are all effective in raising the level of circulating
vitamin D. Of concern, there were only sparse data on other subgroups
cited as being at high risk for the consequences of low vitamin
D, such as dark-skinned individuals and pregnant and lactating
women.
The report found it difficult to define specific blood levels
of markers for vitamin D status that indicate optimal levels for
bone health. One reason for this is that current methods, which
measure serum-25-hydroxy vitamin D as the marker for vitamin D
status, yield highly inconsistent results. As part of its broader
vitamin D initiative, ODS is working with laboratory testing facilities
to standardize the quantification of vitamin D status.
The report investigators were not able to separate the impact
of vitamin D from that of calcium, as most trials studied the effect
of vitamin D plus calcium. The combination of vitamin D3 (daily
dose 700 to 800 IU) and calcium (daily dose 500 to1200 mg) decreased
the risk of falls, fractures and bone loss in the elderly (ages
ranged from 62 to 85 years). The current recommended intake is
400 IU/day for people 51-70 years of age, and 600 IU/day for people
over 70 years of age. Based on the combined data of two trials,
the decreased risk of fractures was seen primarily in the subgroup
of elderly women (average age 85 years) living in nursing homes.
Vitamin D intake above current recommended levels was not reported
to be associated with an increased risk of harms. However, most
trials using higher doses of vitamin D were not adequately designed
to assess potential harms.
“The vitamin D and bone health evidence report provides valuable
insights because it is based on an independent and rigorous examination
of the totality of evidence across all age groups and during pregnancy
and lactation,” said Agency for Healthcare Research and Quality
(AHRQ) Director Carolyn Clancy, M.D. "It Is important that health
care decisions are made using a review of all available evidence
and not solely on the results of individual study reports.”
This report will serve as the framework for a conference, Vitamin
D and Health in the 21st Century: An Update, September 5-6, 2007
on the NIH campus. Although the conference is free of charge and
open to the public, attendees are requested to register at http://vitamindandhealth.od.nih.gov,
where additional conference materials are available. Speakers will
present the salient points of emerging research since the 2003
NIH Vitamin D conference, including the AHRQ evidence report, Effectiveness
and Safety of Vitamin D in Relation to Bone Health. The goals of
the conference are to evaluate the efficacy and safety of vitamin
D, identify gaps in knowledge on the efficacy and safety of vitamin
D, inform NIH and other Federal agencies on vitamin D and health
research priorities, and to disseminate the conference findings
to the broad scientific nutrition community.
The ODS-sponsored report was produced by the University of Ottawa
Evidence-based Practice Center, and is available at:
http://www.ahrq.gov/clinic/tp/vitadtp.htm.
The conference is sponsored by ODS, the National Cancer Institute,
The National Institute of Arthritis and Musculoskeletal and Skin
Diseases, and the American Society for Nutrition ODS was established
at NIH in November 1995 as a result of the Dietary Supplement and
Health Education Act passed by Congress in 1994. The mission of
ODS is to strengthen knowledge and understanding of dietary supplements
by evaluating scientific information, stimulating and supporting
research, disseminating research results, and educating the public
to foster an enhanced quality of life and health for the U.S. population.
For additional information about ODS, please visit http://dietary-supplements.info.nih.gov.
The mission of the Agency for Healthcare Research and Quality
is to improve the quality, safety, efficiency, and effectiveness
of health care for all Americans. Please visit www.ahrq.gov for
additional information.
The Office of the Director, the central office at NIH, is responsible
for setting policy for NIH, which includes 27 Institutes and Centers.
This involves planning, managing, and coordinating the programs
and activities of all NIH components. The Office of the Director
also includes program offices which are responsible for stimulating
specific areas of research throughout NIH. Additional information
is available at http://www.nih.gov/icd/od/.
The National Institutes of Health (NIH) The Nation's
Medical Research Agency is comprised of 27 Institutes
and Centers and is a component of the U. S. Department of Health
and Human Services. It is the primary Federal agency for conducting
and supporting basic, clinical, and translational medical research,
and investigates the causes, treatments, and cures for both common
and rare diseases. For more information about NIH and its programs,
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