Part D. Section 2: Nutrient Adequacy June 2010 pg 26-30

Locally available at [tiki-download_file.php?fileId=1207]

on the web at http://www.cnpp.usda.gov/DGAs2010-DGACReport.htm

D2.16 Elderly are below "official" adequate intake

In 2009 10 ug = 400 IU 15 ug = 600 IU

In late 2010 Institute of Medicine recommended RDA 15ug (600 IU) age 1-69 and 20 ug (800 IU) age 70+

Vitamin D

Strong evidence indicates that many children and a majority of adults do not meet the AI for

vitamin D. Furthermore, a significant portion of the population has deficient or inadequate blood

levels of vitamin D to promote health and prevent chronic diseases, such as poor bone health and

possibly certain types of cancers, cardiovascular disease, and immune-related disorders. This is

especially apparent in people living in northern latitudes, in persons with dark skin, and in

overweight and obese adults.

All children, adults, and the elderly are encouraged to meet the AI for vitamin D by

consuming vitamin D-rich foods in both naturally occurring and fortified forms. Children, adults,

and the elderly with deficient or inadequate blood levels of vitamin D should consume more

vitamin D-rich foods. If necessary, individuals may consider vitamin D supplementation if they

are having difficulty meeting the AI through vitamin D-rich foods.

The DGAC chose not to conduct an independent systematic review of vitamin D due to the

fact that the IOM concurrently empanelled an expert committee to review the DRI for vitamin D.

The previous DRI for vitamin D was established in 1997. The IOM empanelled the committee

because significant new and relevant research had become available to review the existing DRI for

vitamin D (Yetley, 2009). Recommendations from the IOM committee are expected to be available

in Fall 2010.

For this review of vitamin D and health, the DGAC primarily relied upon three different

sources of information: 1) vitamin D intake data from the NHANES (Bailey, 2010a); 2) an American

Journal of Clinical Nutrition (AJCN) supplement (Brannon et al, 2008a) that presented findings from

two sources, including proceedings from the National Institutes of Health (NIH) conference

“Vitamin D and Health in the 21st Century: An Update” held in September 2007 and an NIH

roundtable discussion with expert scientists held after the conference (Brannon et al, 2008b); and 3)

an Agency for Healthcare Research and Quality (AHRQ) evidence report, Vitamin D and Calcium: A

Systematic Review of Health Outcomes (Chung, 2009) prepared for use by the 2009-2010 IOM

committee. The results of the DGAC’s review are presented below.

Vitamin D and health: Adequate vitamin D status, which depends upon dietary intake and

cutaneous synthesis, is important for health (Brannon et al, 2008a). Well-established research

demonstrates the importance of vitamin D for bone health. Vitamin D deficiency results in rickets in

children and osteomalacia in adults (Brannon et al, 2008a). In adults and older adults, adequate

vitamin D reduces risk of fractures (Looker, 2010). Recent evidence suggests that vitamin D is

important for other body systems (Brannon et al, 2008a; Nutrition Reviews, 2007). Emerging research

has shown a reduced risk for type 1 diabetes, some cancers, autoimmune diseases, and infectious

diseases (Brannon, 2008b; Chung, 2009). Further well-designed, dose-response research is needed to

fully establish the relationship between vitamin D and many of these outcomes (Chung, 2009).

Vitamin D intake: Results from 2003-2006 NHANES data indicate that the majority of the

population does not meet the AI for vitamin D (Bailey, 2010a). With diet alone, less than 10 percent

of men and women older than 50 years meet the AI, and less than 2 percent of adults older than 70

years meet the AI (10ug/day for 51 to 70 years of age; 15ug /day for 71 years of age and older)

(Figure D2.16). Approximately 47 percent and 53 percent, respectively, of adolescent girls and boys

older than 9 years meet the AI. About 53 percent and 67 percent of girls and boys, respectively, aged

4 to 8 years, meet the AI (5ug /day). The only population subgroup that comes close to meeting the

AI with diet alone, due to fluid milk consumption, is children, with 70 percent and 72 percent of

girls and boys, respectively, aged 1 to 3 years, meeting the AI of 5 g per day.

When supplements are added to dietary intake, the percentage of children and adults who meet

the AI improves. Thirty-seven percent of the population consumes supplements that contain

vitamin D. However, even with combined dietary intakes and supplementation, a majority of adults

still do not meet the AI:

less than 50 percent of men and women, aged 19 to 30 years;

less than 60 percent of men and women, aged 31 to 50 years;

less than 45 percent of adults older than 50 years; and

less than 25 percent of adults older than 70 years.

Less than 1 percent of the population exceeds the UL for vitamin D intake (Bailey, 2010a).

These vitamin D intakes are compared against the 1997 AI for vitamin D. Should the IOM

determine new AIs for vitamin D, comparisons of intakes to AI standards should be adjusted

accordingly.

Vitamin D status: The criterion used by the IOM for setting the AI in 1997 was the normal

level of serum 25(OH)D concentration, an indicator of vitamin D status. The 1997 25(OH)D

criterion of greater than or equal to 27.5 nmol/L for children up to age 18 years and greater than or

equal to 30 nmol/L for adults aged 19 years and older set by the IOM was based upon associations

with bone growth in children and normal parathyroid concentrations in adults. This criterion has

been brought into question based on new information on the relationship of serum 25(OH)D to

health, the relationship of vitamin D intake to serum 25(OH)D concentration, vitamin D status of

the US population, and safety of vitamin D status, as summarized in the September 2008

supplement of the American Journal of Clinical Nutrition and elsewhere (Dawson-Hughes, 2005;

Norman, 2007). The DGAC expects that the IOM empanelled committee will carefully evaluate the

criteria for determining deficient, marginal or insufficient, and adequate serum vitamin D

concentrations. Until a determination is made by the IOM panel, the DGAC must independently

consider published evidence of potential thresholds for adequacy regarding health outcomes and

implications related to food guidance.

Contributing scientists to the 2007 NIH roundtable discussion used the following cutoff points

to evaluate vitamin D adequacy: less than 27.5 nmol/L, less than 50 nmol/L, and less than 75

nmol/L when analyzing blood samples from the 2002-2004 NHANES (Yetley, 2008).

Approximately 30 percent of people aged 12 years and older had serum 25(OH)D levels lower than

50 nmol/L. For children, aged 1 to 11 years, approximately 15 percent had serum 25(OH)D levels

lower than 50 nmol/L. Slightly more women than men had serum 25(OH)D concentrations lower

than 50 nmol/L. Yetley (2008) further reported an inverse association of body fatness and BMI on

serum 25(OH)D concentrations. Leaner women, regardless of the method used to assess body

fatness, had higher concentrations of serum 25(OH)D. A more recent evaluation in children, aged 1

to 11 years, using 2001-2006 NHANES findings reported that 18 percent of children in this age

range had serum 25(OH)D concentrations below 50 nmol/L (Mansbach, 2009). An even higher

percentage of non-Hispanic black and Hispanic children had serum 25(OH)D concentrations below

50 nmol/L.

These data should be interpreted with caution because of lingering questions related to

measurement drift from assay method changes and completeness of data (Looker, 2008; Yetley,

2008). However, using the NHANES values, after adjusting for an apparent measurement drift,

serum 25(OH)D concentrations for the US population were lower in the years 2000 to 2004 than in

1988 to 1994 (Looker, 2008). In adults, increases in BMI, reductions in fluid milk intakes, and

increases in sun protection appeared to contribute to this decline (Looker, 2008).

Sources of vitamin D: Vitamin D can be obtained through dietary sources, cutaneous

synthesis, and supplementation. Fatty fish, such as salmon and herring, is the primary natural food

source of vitamin D. Based on 2005-2006 NHANES data, fish and shellfish provide 8.6 percent of

the vitamin D intake in the US. All fluid milk must be fortified with vitamin D, and other foods

(e.g., cereals, margarine, and yogurt) and beverages (e.g., orange juice) are also commonly fortified.

The best sources of vitamin D include fortified fluid milk, fatty fish such as salmon and trout,

portabella mushrooms, and fortified orange juice (Table D2.10). Slightly more than 52 percent of

the total intake comes from vitamin D-fortified fluid milk, milk drinks and desserts, and yogurt

(Table D2.11). Fortified cereals account for an additional 6.5 percent of intake, and meat, poultry,

and eggs together account for 11.2 percent. Various vitamin D-fortified foods differ in the amounts

of vitamin D that they contain.

The USDA Food Patterns include vitamin D from fortified fluid milk, fortified ready-to-eat

cereals, fortified butter and margarine, and the naturally occurring vitamin D in meat, poultry, fish,

and eggs. The food patterns that contain 3 cup equivalents from the fluid milk and milk products

food group provide sufficient vitamin D to meet the current AI for all children and adults, aged 19

to 50 years (i.e., 5 ug/day). However, the patterns do not provide sufficient vitamin D for adults

over 50 years (i.e., 10 ug/day). The food patterns at 1000 to 1400 calories that contain only 2 cup

equivalents from the fluid milk and milk products group do not provide adequate vitamin D to meet

the AI of 5 ug/day for children, aged 2 to 8 years. Additional vitamin D could be obtained by

selecting more natural food sources of vitamin D, such as certain fish, and fortified sources of

vitamin D, such as fortified orange juice. In addition, choosing fortified fluid milk or yogurt rather

than including cheese or non-fortified yogurt when making selections from the fluid milk and milk

products food group would increase vitamin D intakes to adequate amounts for all age-sex groups,

except those over 70 years of age. When necessary, individuals may consider vitamin D

supplementation along with dietary intake, especially in older individuals because endogenous

production of vitamin D from sun exposure is reduced by more than 50 percent in elderly

populations.

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