FROM:
J Am Diet Assoc. 2007 (Aug); 107 (8): 1322–1332 ~ FULL TEXT
Rhonda S. Sebastian, MA, Linda E. Cleveland, MS, RD,
Joseph D. Goldman, MA, Alanna J. Moshfegh, MS, RD
US Department of Agriculture,
Agricultural Research Service,
Food Surveys Research Group,
Beltsville, MD 20705, USA.
Rhonda.Sebastian@ars.usda.gov
OBJECTIVE: To measure nutrient intake adequacy of vitamin/mineral supplement users and nonusers aged 51 years and older, determine the efficacy of supplement practices in compensating for dietary deficits, and identify predictors of supplement use.
DESIGN: Analyses of two 24-hour recalls, demographic variables, and attitude questions collected during the Continuing Survey of Food Intakes by Individuals and Diet and Health Knowledge Survey in 1994 to 1996. Data were weighted to be representative of older Americans.
SUBJECTS: Four thousand three hundred eighty-four adults aged 51 years and older (1,777 daily supplement users, 428 infrequent users, and 2,179 nonusers) residing in households in the United States.
STATISTICAL ANALYSES: Usual nutrient intake distributions were estimated using the Iowa State University method. The Estimated Average Requirement (EAR) cutpoint method was applied to determine the proportion of older adults not meeting requirements before and after accounting for nutrient intake from supplements. Student t tests were used to assess differences between users and nonusers. Logistic regression was used to determine sociodemographic and attitudinal predictors of supplement use.
RESULTS: For one or more of the sex-age groups studied, a significantly smaller proportion of supplement users than nonusers had intakes from food alone below the EAR for vitamins A, B-6, and C; folate; zinc; and magnesium. Even so, less than 50% of both users and nonusers met the EAR for folate, vitamin E, and magnesium from food sources alone. Overall, supplements improved the nutrient intake of older adults. After accounting for the contribution of supplements, 80% or more of users met the EAR for vitamins A, B-6, B-12, C, and E; folate; iron; and zinc, but not magnesium. However, some supplement users, particularly men, exceeded Tolerable Upper Intake Levels for iron and zinc and a small percentage of women exceeded the Tolerable Upper Intake Level for vitamin A. Significant sociodemographic factors related to supplement use for older men were age group, metropolitan area, and educational status. Race, region, smoking status, and vegetarian status were significant factors for women. Attitude about the importance of following a healthful diet was a consistent predictor of supplement use for both men and women.
CONCLUSIONS: A large proportion of older adults do not consume sufficient amounts of many nutrients from foods alone. Supplements compensate to some extent, but only an estimated half of this population uses them daily. These widespread inadequacies should be considered when developing recommendations for supplement use for clients in this age group. Modifying dietary attitudes may result in a higher rate of supplement use in this at-risk population.
From the FULL TEXT Article:
Background
Analyses of nationwide survey data have shown that
a large percentage of older adults do not receive
recommended amounts of many nutrients from food
alone [1–11]. Other measures, such as the Healthy Eating
Index, also indicate that the diets of older adults need
improvement and may leave them susceptible to nutrition-related problems [12, 13]. This is of particular concern
because conditions prevalent in this population, including
chronic diseases and absorption problems, can
compromise nutritional status [14–16]. At the same time,
a growing proportion of older adults are using vitamin
and mineral supplements, which can substantially increase
nutrient intake and counter some of these shortfalls
[17–19]. Little is known about the effectiveness of
vitamin/mineral supplements in appropriately compensating
for dietary deficits.
With the introduction of the Dietary Reference Intakes
(DRIs), new standards are available for the assessment of
nutrient intakes. The establishment of Estimated Average
Requirements (EARs) makes it possible, for the first time, to estimate the prevalence of nutritional inadequacy in population
groups. Additionally, the Tolerable Upper Intake
Levels (ULs) provide cutpoints for estimating the percentage
of the population of interest that is at potential risk of
adverse effects due to overconsumption of a nutrient [20].
These two components of the DRIs provide new opportunities
for assessing nutrient intake and evaluating the influence
of supplement use on dietary status.
Although supplement use provides potential benefits in
increasing nutrient intakes, there are potential drawbacks
[21–25]. The extensive use of supplements by older
adults increases the possibility for overconsumption of
nutrients. The American Dietetic Association’s position
paper on food fortification and dietary supplements [26]
notes that documented cases of toxicity are often caused
by supplementation. In fact, the ULs were developed
largely in response to the growing use of supplements and
fortified foods [20].
Considering the potential for both positive and negative
effects on overall nutrient intake, an important question
to ask is what factors influence supplement use.
Characteristics associated with taking supplements are
well documented. Users generally consume more nutrient-
dense diets and vary significantly from nonusers in
many sociodemographic factors, including age, sex, race,
education status, and income level [17, 27–45]. Research is
more limited on the effect of more modifiable factors, such
as attitudes about diet and health, on supplement use.
The Diet and Health Knowledge Survey, a component of
the US Department of Agriculture’s Continuing Survey of
Food Intakes by Individuals (CSFII), was designed to
provide information about people’s attitudes and knowledge
on topics that could affect their dietary intake [46].
Currently, the Diet and Health Knowledge Survey offers
the only national survey data that links attitudes about
diet and health with dietary behavior, including supplement
use.
The purpose of this study was to examine the effects of
supplement use on nutrient intake and dietary adequacy
for adults aged 51 years and older, and to identify determinants
of supplement use. Objectives were to compare
the nutrient intake adequacy of older adults who consumed
vitamin/mineral supplements daily to those who
did not, to estimate the contribution of supplements to
total nutrient intake and the associated reduction in nutritional
inadequacy, to determine if supplement use creates
nutrient intake excesses among older adults, and to
identify sociodemographic and attitudinal factors that
are predictive of supplement use.
METHODS
Data Source and Sample
Data for this study were drawn from US Department of
Agriculture’s 1994–96 CSFII and Diet and Health Knowledge
Survey. The CSFII- Diet and Health Knowledge
Survey is a nationally representative survey of noninstitutionalized
individuals in all 50 states and Washington,
DC. A complex multistage, area probability sample design
was used to select persons within households. Individuals
aged 51 years and older were oversampled. Details
of the sample design and methods have been
enumerated elsewhere [46]. Dietary intake data were
collected using two in-person, interviewer-administered
24–hour recalls conducted 3 to 10 days apart. The Diet
and Health Knowledge Survey was administered by telephone
to one adult sample person in the household 3
weeks after the second intake interview.
Supplement information was collected through a series
of questions following the first 24–hour recall. Two handcards
were used to query respondents on the types of
vitamin/mineral supplements taken (ie, multivitamin,
multivitamin with iron, combination of vitamin C and
iron, and single vitamins and/or minerals); and if indicated,
what specific types of single vitamins/minerals
were consumed (eg, vitamin A, vitamin C, calcium, and
iron). The frequency of consumption (taken daily or less
often) was also obtained, but not the specific quantity.
The amount of each nutrient in the supplement (the
formulation) and the brand name were not collected.
Data from the CSFII sample were used to determine
nutrient intake adequacy of supplement users and nonusers.
Data from the smaller Diet and Health Knowledge
Survey sample were used to identify attitudinal and sociodemographic
predictors of supplement use. A total of
4,384 respondents aged 51 and older provided two complete
24–hour recalls in the CSFII. Supplement users
were defined as individuals who took any kind of vitamin
or mineral supplement every day. Almost 10% of the
sample (M = 428) was classified as infrequent supplement
users and excluded from the analysis. These individuals
reported that they took vitamin or mineral supplements
“every so often.” The remaining sample of 3,956 supplement
users and nonusers was used in assessments of
nutrient intake adequacy. The infrequent users were
then added back to the sample, and information from the
2,571 respondents aged 51 years and older providing
complete responses to the Diet and Health Knowledge
Survey attitude questions were used in the analysis to
identify predictors of supplement use.
Calculating Nutrient Intake from Foods and Supplements Foods.
Some nutrients required conversion to standardized
measurement units before comparison of dietary intakes
to the DRIs could be made. Vitamin A had to be
converted to retinol activity equivalents, vitamin E to
milligrams αtocopherol, and folate to dietary folate
equivalents. For vitamins A and E, a special database
developed by the US Department of Agriculture, which
translated intake estimates of dietary vitamin A from
retinol equivalents into retinol activity equivalents and
dietary vitamin E from αtocopherol equivalents into milligrams αtocopherol was employed [47]. For folate, the
food composition database did not distinguish between
the naturally occurring form and the synthetic form (folic
acid), so all contributions to folate intake by food were
assumed to be the less bioavailable folate form. One microgram
converted directly to 1 µg dietary folate equivalent.
Because the dietary data for this study were from
1994 through 1996 and widespread fortification of enriched
cereal-grain foods with folic acid was not completed
until 1998, the underestimation of total folate intake
is not as great as it would be if folate fortification had
been in place [48–51]. Nonetheless, dietary inadequacy for
folate is overestimated to some immeasurable degree.
Supplements.
Because brand names and formulations of
supplements were not collected in CSFII, assignment of
nutritive values for both single nutrient and multivitamin-
mineral supplements was based on the nutrient profile
of the most frequently reported supplement of that
type in the 1999–2000 National Health and Nutrition
Examination Survey (NHANES). This is following the
procedure used in NHANES when brand and/or formulation
were not available [52]. The source of the nutrient
values for the supplements was the NHANES Dietary
Supplement Database [52]. Before conversions to standardized
units could be made for vitamins A and E, and
folate, assumptions concerning the form of the nutrient in
the supplement were required. Vitamin A in multivitamin-
mineral supplements was assumed to be comprised
of 60% retinol and 40% beta-carotene, which was the
formulation most commonly seen in supplements recorded
in the NHANES Dietary Supplement Database.
Dietary vitamin A measured in international units was
multiplied by 0.30 and beta-carotene by 0.15 to convert to
retinol activity equivalents [53]. For vitamin E, the factor
of .45 for all-racemic αtocopherols was used for all supplemental
sources to convert to milligram αtocopherol
units [54]. All supplemental folate was considered to be
folic acid, and intake in micrograms was multiplied by 1.7
to convert to dietary folate equivalents [55, 56].
Method for Comparing Intakes to DRIs
To assess the nutrient intake adequacy of groups using
the DRIs, an estimate of the usual or long-term intake
distribution is needed [20]. For this study, the Iowa State
University method, implemented with C-Side software
(version 1.02, 1997, Department of Statistics, Iowa State
University, Ames), was used to estimate the usual nutrient
intake distributions and apply the EAR cutpoint
method [57, 58]. Estimates were generated for percentages
of individuals below the EAR and above the UL. The
proportion of older adults considered to be inadequate for
each nutrient was estimated as the percentage whose
usual intake fell below the EAR for that nutrient [57].
To account for contributions to nutrient intake from all
sources, nutrient values assigned to each type of supplement
reported were added to the nutrient intake contributed
by food. Because supplement users were defined as
those who took supplements every day, the contribution
from supplements was applied to both of the dietary
intake days. The DRIs used in these analyses were taken from reports
of the National Academy of Sciences on vitamin A,
iron, and zinc [53]; vitamin C and vitamin E [54]; calcium
and magnesium [59]; and vitamin B-6, folate, and vitamin
B-12 [55].
Identification of Factors Related to Supplement Use
Sociodemographic variables for this analysis included
variables shown in previous studies to be related to supplement
use, including sex, age, race, poverty status, and
education level [17, 27–31, 33–40, 42, 44]. In addition, two
attitude scales, composed of 11 questions each, were derived
from Diet and Health Knowledge Survey data. The
first scale was developed from questions on perceived
adequacy of the respondent’s own diet. Respondents indicated
if they believed their diets were too low, too high,
or about right in each of 11 nutrients. Higher scores
indicated a more favorable assessment of the healthfulness
of one’s daily food intake. The second scale measured
the importance the respondent placed on following the
1990 Dietary Guidelines for Americans—the most recent
government recommendations at the time of CSFII- Diet
and Health Knowledge Survey data collection [60].
Higher scores indicated a greater importance placed on
incorporating the recommendations into one’s own diet.
Statistical Analyses
The SUDAAN program (version 9.0, 2005, Research Triangle
Institute, Research Triangle Park, NC) and SAS
(release 8.2, 2001, SAS Institute Inc, Cary, NC) were used
for all statistical calculations. Student t tests were conducted
to measure for significant differences between
supplement users and nonusers in proportions below the
EAR for each analyzed nutrient. Dietary intakes of nonusers
were tested against the dietary (food only) intake of
supplement users; and the total intake of users, including
the supplement contribution. A P level of 0.001 was applied
to account for the large number of comparisons
made.
χ2 analyses were conducted to determine if there were
differences in supplement use between men and women,
and between age groups.
Logistic regression was performed using the Diet and
Health Knowledge Survey sample to identify sociodemographic
variables and attitudes associated with the decision
to use supplements. Contrasts were done when a
variable was significant in the model and the variable
had more than two response choices.
RESULTS
Table 1
Table 2
|
Table 1 shows that supplement use was widespread
among older adults. In CSFII, 37% of men and 47% of
women consumed at least one type of supplement every
day. Significant differences were noted between men and
women, but not between age groups.
Overall, multivitamin-multimineral supplements were
the most frequently reported supplement type for both
men and women (Table 2) with 34% of all older men and
41% of all older women taking one. Among all supplement
users, 74% of men and 70% of women aged 51 years and
older took this type. Vitamin C and vitamin E were the
most commonly mentioned single vitamin or mineral supplements
with 19% to 34% of respondents reporting use.
Calcium supplements were popular among older women;
26% of users aged 51 to 70 years and 18% of users aged 71
years and older took them.
Comparison of Nutrient Adequacy from Food between Users and Nonusers
Table 3
Table 4
|
Tables 3 and 4 present the mean usual daily nutrient
intake and intake at the 25th, 50th, and 75th percentiles
for supplement users and nonusers. For supplement users,
estimates are presented for intake from food sources
only and for the combined intake from both food and
supplements. Also shown are percentages of the population with intakes below the EAR (ie, percentages with
inadequate intakes). Data are shown separately for men
(Table 3) and women (Table 4).
When considering nutrient intake from food sources
alone, generally smaller proportions of supplement users
than nonusers had inadequate intakes. Intakes of vitamins
A and C were significantly higher for users than
nonusers in both age groups of men. Vitamin B-6 and
magnesium were significantly higher for users as compared
to nonusers in both age groups of women. More
than 50% of both supplement users and nonusers had
inadequate intakes of folate, vitamin E, and magnesium
from food. In addition, for most of the sex/age groups
studied, more than 25% had inadequate intakes of vitamins
A, B-6, and C from food. Iron was the only nutrient
studied for which the prevalence of inadequate intakes
among older adults was consistently low; 3% or fewer
older adults had intakes below the EAR.
Table 5
|
It was not possible to determine proportions of the
population with inadequate calcium intakes because the
DRI is expressed as an Adequate Intake and not as an
EAR. Although mean intakes from food alone were higher
among supplement users than nonusers (Table 5), the
only statistical difference between users and nonusers
was among men aged 51 to 70 years.
The nutrient intake from food alone was not sufficient
to exceed the ULs for any of the nutrients in this analysis.
This was true for men and women in both age groups,
regardless of supplement use.
Contribution of Supplements to Nutrient Intake
Regular supplement use, in effect, reduced the percentage
of older adults with inadequate intakes by at least
three fourths for most nutrients (Table 3 and 4). Folate
and vitamin E intakes were particularly improved by
supplements. Food-only intakes of these nutrients were
inadequate for 57% to 96% of supplement users. After
accounting for supplements, only 6% to 17% were classified
as inadequate.
When the nutrient contribution of supplements was
considered, significant differences were found between
users and nonusers in percentages with inadequate intakes
for nearly all the nutrients studied. Mean intakes of
vitamin B-12 and iron were boosted by supplements, but
the percent of this population with inadequate intakes
was largely unaffected, because most older adults met the
EAR from food intake alone. An exception was that significantly
more nonuser women aged 71 years and older
had inadequate intakes of vitamin B-12 compared to the
total intake of supplement users in this sex/age group.
Although for the most part the percent meeting the EAR
was not significantly increased for vitamin B-12 and iron, supplements did affect intake. Mean intakes from food
and supplements for users were significantly different
from total intake of nonusers. Supplements more than
doubled vitamin B-12 intake for men and women, and
this may be of benefit because the absorption of naturally
occurring vitamin B-12 may be problematic in older
adults [55].
Older men and women who consumed supplements had
significantly higher total calcium intakes than nonusers
of these products (Table 5). The proportion reaching or
exceeding the Adequate Intake increased from 15% to
29% for men aged 51 to 70 years. Large improvements
were also found for older women and men aged 71 years
and older.
Supplements and Overconsumption of Nutrients
Table 6
|
Fewer than 3% of men in both age groups had total
intakes that exceeded the UL for vitamins B-6, and C,
and calcium, indicating that risk of adverse effects from
excesses of these nutrients is low in this population group
(Table 6). Supplement use did, however, result in intakes
that exceeded the ULs for iron and zinc for 10% or more
of older men.
Women in both age groups exceeded the UL for iron
and zinc, but they did so in smaller proportions than the
men. Unique to the women was that a higher proportion
(5% to 9%) exceeded the UL for vitamin A than the
proportion of men (4%) who did so.
Demographic and Attitudinal Predictors of Supplement Use
Table 7
|
Predictors of supplement use were different for older
men than for older women (Table 7). Men aged 71 years
and older and those living in metropolitan areas were
significantly more likely to consume supplements compared
to men in the 51– to 70–year age group and those
in nonmetropolitan areas, respectively. Education status
was also a predictor of supplement use for men.
Contrasts showed that significant differences were
found between the least educated men (less than high
school completion attained) and those with either a
high school education or formal education beyond high
school. No differences were noted between the two
higher education categories. For the women, race, region,
smoking status, and vegetarian status were significant
predictors of supplement use. White women
were more likely to take supplements than all other
racial groups combined, and were twice as likely to
take supplements as Hispanic women. Residence in the
western region of the United States indicated greater
prevalence of supplement use than in all other regions
together; those in the northeast and midwest were
about half as likely to be users. Women who were
nonsmokers were more likely to consume supplements
than women who smoked, and the small percentage of
older women who were vegetarians (4%) were twice as
likely to be supplement users as their nonvegetarian
counterparts.
Of the two attitude variables included in the logistic
regression model, the personal importance of consuming a diet consistent with Dietary Guidelines recommendations
was a significant predictor of supplement use. Interestingly,
it was also the only factor that was significant
for both men and women. Attitudes related to the perception
of the adequacy of one’s own diet were not related to
supplement use.
DISCUSSION
This study provides estimates of the prevalence of nutrient
inadequacies and excesses among older adults, and
compares intakes of supplement users and nonusers. The
estimates cover total nutrient intake from both foods and supplements. To our knowledge, this is the first study to
use DRIs in combination with estimates of usual total
nutrient intake to evaluate intakes in this population.
The results are consistent with those from previous
studies [27, 32, 38, 40, 41, 43–45] in showing that, generally,
supplement users consume more nutritious diets than
nonusers. We found that supplement users were more
likely to have adequate nutrient intakes from food alone
than nonusers for many of the nutrients studied. However,
both supplement users and nonusers had large
shortfalls in intake from food alone for several nutrients,
most notably folate, vitamin E, and magnesium. Supplementation
was most beneficial in improving intakes for
these nutrients. Nutrients for which little benefit from
supplementation was observed were vitamin B-12 (assuming
adequate absorption) and iron because most older
adults met the EARs from foods alone. Among users, 80%
or more met EARs with their total intake for all nutrients
studied except magnesium.
The folate estimates here underestimate current intakes
because the US Food and Drug Administration did
not mandate fortification of grain products until 1998,
after data for this study were collected; however, they
provide a benchmark for comparison to post-fortification
levels. Fortification was expected to add 70 to 130 µg to
the daily diet, but subsequent studies have shown that
intakes have been increased by 200 µg or more
[48, 49, 61, 62]. Based on our study, most older adults
would meet adequacy standards if diets provided a net
increase of 200 µg/day. Nevertheless, recent analyses
using NHANES 2001–2002 data and the accompanying
US Department of Agriculture’s Food and Nutrient Database
for Dietary Studies 1.0, which accounts for current
fortification levels found that depending on the sex/age category, 7% to 21% of older adults still had inadequate intakes from food alone [63]. Further study is needed to
determine if folate taken as a dietary supplement should
be recommended for this population to improve intake
and achieve dietary adequacy.
Most older adults appear to obtain adequate amounts
of vitamin B-12 from dietary sources. However, the Institute
of Medicine has advised that individuals aged 50
years and older obtain vitamin B-12 from supplemental
sources because 10% to 30% of older adults may not be
able to absorb the naturally occurring form found in foods
[55]. With databases available for these analyses, it was
not possible to differentiate between the naturally occurring
form and the synthetic form added to fortified foods
for estimating intake. In the future, with such a database,
research can determine if supplemental vitamin
B-12 is needed to meet EARs in addition to the vitamin
B-12 typically provided by the food supply.
Supplements boosted total intakes of iron and zinc so
that a considerable proportion of older adults, particularly
men, exceeded the UL. Due to the adverse effects
associated with iron overload and the possibility of its
association with coronary heart disease, the Institute of
Medicine has recommended that men and postmenopausal
women avoid iron supplements and highly fortified
foods [53]. Data from this study support those recommendations.
In contrast, zinc intake inadequacy
before supplementation affected 20% or more of the population.
This finding is consistent with other research
that has found that older adults, particularly those aged
71 years and older, are the population at greatest risk of
zinc intake inadequacy [4, 6, 7, 11, 64, 65]. At the same time,
data from this study indicate that approximately 15% of
men aged 51 to 70 years and 10% of men aged 71 years
and older who are supplement users are exceeding the
UL for zinc. Excess consumption of zinc is associated with
a risk of reduced copper status, impaired immune response,
and lowered plasma high-density lipoprotein cholesterol
levels [53]. Supplementation of zinc appears to be
needed by a sizable proportion of older men and women,
but should be undertaken prudently.
The UL for vitamin A was exceeded by 9% of women
aged 51 to 70 years and by 5% of women aged 71 years
and older who took supplements. This finding is of concern
because long-term vitamin A intake ≥3,000 µg per
day has been associated with hip fractures in postmenopausal
women [66–68]. Most of the supplemental vitamin
A was consumed in a multivitamin/multimineral supplement.
An imputed retinol:beta-carotene ratio was used
for estimating intake based on the most commonly reported
supplement of that type in NHANES 1999–2000.
The percentage of women actually consuming vitamin A
in levels above the UL, and therefore at risk of adverse
effects, may be higher or lower if the particular brands of
supplements consumed have a different ratio. Further
investigation with more precise data is needed to identify
if excess vitamin A intake by supplementation is an issue
affecting large numbers of older women.
A secondary objective of the study was to identify characteristics
associated with supplement use with particular
emphasis on more modifiable factors like attitudes.
Whereas sociodemographic factors related to supplement
use varied by sex, attitudes about the importance of following
a healthful diet consistent with expert recommendations
was a significant predictor for both men and
women. Those respondents most concerned about their
diets and dietary recommendations were more likely to
take supplements. These findings suggest that encouraging
positive attitudes about a healthful diet in combination
with nutrition guidance and appropriate supplement
information may result in promoting advantageous use of
supplements by this at-risk population.
The fact that the CSFII 1994–1996 is more than 10
years old raises questions as to the applicability of
these findings to current dietary adequacy of older
adults. However, nutrient intakes from food in this
study are comparable to those reported in assessments
using the NHANES 2001–2002 data, suggesting that
there has been little change in nutrient intake from
food during this time period [63]. Using approximate t
tests, we investigated changes from 1994 to 1996 to
2001 to 2002 in the percent of the older adult population
meeting the EAR for the nutrients included in this
study. Except for folate and calcium, no differences
were found. Folate intake dramatically increased by
more than 200 µg in all of the age/sex groups due to
changes in fortification regulations implemented after
the data for this study were collected. The mean calcium
intake from food increased significantly for men
aged 51 to 70 years (611 mg±12 to 874 mg±30) and
women aged 51 to 70 years (589 mg±17 to 701 mg±19).
Results concerning the other eight nutrients we analyzed
should apply now as they do to a decade ago.
Methodologic limitations demand caution be taken in
interpreting results from this research. Supplement use
was not tied to a specific day of intake, and the validity of
applying quantitative intake assessment to frequency
data has been questioned [69]. If the supplement information
had been collected to match the days of the 24–
hour food recalls, it would be better suited to the statistical
requirements for intake assessment [69]. Another
methodologic limitation is the need for assumptions due
to the lack of specificity of the available supplement data.
Because brand name information was not collected, estimates
were derived using formularies reflecting the composition
of the most commonly reported supplement of
that type in NHANES 1999–2000. If a respondent did not
take the most frequently used product of that type, this
imputation may not accurately reflect what nutrients
were actually consumed. Moreover, formulations of supplements
are changed frequently, and a specific supplement
manufactured in 1994 through 1996 may not be
identical to the 1999 through 2000 product. In addition,
whereas frequency information on supplement use was
collected (ie, every day/infrequently/not at all), the quantity
of supplements taken was not obtained. Last, supplement
use is subject to misreporting. Respondents may not
remember any or all the supplements they take or how
often they take them. Because of these limitations, the
proportions of supplement users meeting EARs and exceeding
ULs may be higher or lower than reported in this
study. Also absent from these intake data is information
on supplements such as antacids and medicinal products
that may have been taken and would contribute nutrients.
Older adults are heavy consumers of these products
[17, 19, 27, 28, 33, 70]. Calcium intake in particular may be underestimated due to lack of data on intake of antacids,
which are promoted as calcium supplements and popular
among the older population [71].
CONCLUSIONS
Supplements had a positive influence on nutrient adequacy for men and women aged 51 years and older. Whereas dietary modifications to improve intake are paramount, the use of supplements by older adults appears beneficial to attain nutrient adequacy. To avoid exceeding the UL, this population should avoid the routine supplemental intake of certain nutrients including vitamin A in the form of retinol and iron.
The link between dietary attitudes and subsequent behavior, including supplement use, needs further research. Currently there is no attitude data collected in conjunction with dietary information on a nationwide scale [72, 73]. Comprehensive attitude data related to dietary issues needs to be obtained to investigate possible avenues for intervention to encourage healthful behavior.
REFERENCES
US Department of Agriculture.
Table Set 10: Results from USDA’s 1994–96 Continuing Survey of Food Intakes
by Individuals and 1994–96 Diet and Health Knowledge Survey
Ford ES, Mokdad AH.
Dietary magnesium intake in a national sample
of US adults.
J Nutr. 2003;133:2879-2882.
Bell RA, Quandt SA, Spangler JG, Case LD.
Dietary calcium intake
and supplement use among older African American, white and Native
American women in a rural southeastern community.
J Am Diet
Assoc. 2002;102:844-847.
Ervin RB, Kennedy-Stephenson J.
Mineral intakes of elderly adult
supplement and non-supplement users in the Third National Health
and Nutrition Examination Survey.
J Nutr. 2002;32:3422-3427.
Fletcher RH, Fairfield KM.
Vitamins for chronic disease prevention in
adults: Clinical applications.
JAMA. 2002;287:3127-3129.
Briefel RR, Bialostosky K, Kennedy-Stephenson J, McDowell MA,
Ervin RB, Wright JD.
Zinc intake of the US population: Findings from
the third National Health and Nutrition Examination Survey, 1988-
94.
J Nutr. 2000;130(suppl):1367S-1373S.
Cid-Ruzafa J, Caulfield LE, Barron Y, West SK.
Nutrient intakes and
adequacy among an older population on the eastern shore of Maryland:
The Salisbury Eye Evaluation.
J Am Diet Assoc. 1999;9:564-571.
Enns CW, Goldman JD, Cook A.
Trends in food and nutrient intakes
by adults: NFCS 1977-78, CSFII 1989-91, and CSFII 1994-95.
Fam
Econ Nutr Rev. 1997;10:16-31.
Dietary Intake of Vitamins, Minerals, and Fiber of Persons Ages 2
Months and Over in the United States:
Third National Health and
Nutrition Examination Survey, Phase 1, 1988-91.
Hyattsville, MD: National Center for Health Statistics; 1994.
Advance data from Vital and Health Statistics, No. 258.
Bialostosky K, Wright J. Kennedy-Stephens J, McDowell M, Johnson
C.
Dietary intake of macronutrients, micronutrients and other dietary
constituents: United States 1988-94.
Vital Health Stat 11. 2002;245:
1-158.
Hallfrisch J, Muller DC.
Does diet provide adequate amounts of
calcium, iron, magnesium, and zinc in a well-educated population?
Exp Gerontol. 1993;28:473-483.
Juan WY, Lino M, Basiotis PP.
Quality of Diets of Older Americans.
Alexandria, VA: Center for Nutrition Policy and Promotion; 2004.
Nutrition Insight 29.
Finke MS, Huston SJ.
Healthy Eating Index scores and the elderly.
Fam Econ Nutr Rev. 2003;15:67-73.
Chandra RK.
Impact of nutritional status and nutrient supplements
on immune responses and incidence of infection in older individuals.
Ageing Res Rev. 2004;3:91-104.
Fairfield KM, Fletcher RH.
Vitamins for chronic disease prevention in
adults: Scientific review.
JAMA. 2002;287:3116-126.
Russell RM.
Factors in aging that effect the bioavailability of nutrients.
J Nutr. 2001;131(suppl 4):S1359-S1361.
Millen AE, Dodd KW, Subar AF.
Use of vitamin, mineral, nonvitamin,
and nonmineral supplements in the United States:
The 1987, 1992,
and 2000 National Health Interview Survey Results.
J Am Diet Assoc.
2004;104:942-950.
Briefel RR, Johnson CL.
Secular trends in dietary intake in the
United States.
Annu Rev Nutr. 2004;24:401-431.
Messerer M, Johanasson SE, Wolk A.
Use of dietary supplements and
natural remedies increased dramatically during the 1990s.
J Intern
Med. 2001;250:160-166.
Institute of Medicine, Food and Nutrition Board.
Dietary Reference Intakes: Applications in Dietary Assessment.
Washington, DC: National Academies Press; 2000.
Bjelakovic G, Nikolova D, Simonetti RG, Gluud C.
Antioxidant supplements
for prevention of gastrointestinal cancers: A systematic
review and meta-analysis.
Lancet. 2004;364:1219-1228.
Omenn GS, Goodman GE, Thornquist MD, Balmes J, Cullen MR,
Glass A, Keogh JP.
Effects of a combination of beta carotene and vitamin
A on lung cancer and cardiovascular disease.
N Engl J Med. 1996;
334:1150-1155.
Herbert V, Shaw S. Jayatilleke E, Stopler-Kasdan T.
Most free-radical
injury is iron-related: It is promoted by iron, hemin, holoferritin
and vitamin C, and inhibited by deferoxamine and apoferritin.
Stem
Cells. 1994;12:289-303.
Nelson RL, Davis FG, Sutter E, Sobin LH, Kikendall JW, Bowen P.
Body iron stores and risk of colonic neoplasia.
J Natl Cancer Inst.
1994;86:455-460.
Cook JD, Dassenko SA, Whittaker P.
Calcium supplementation: Effect
on iron absorption.
Am J Clin Nutr. 1991;53:106-111.
Position of The American Dietetic Association:
Food fortification and
dietary supplements.
J Am Diet Assoc. 2001;101:115-125.
Archer SJ, Stamler J, Moag-Stahlberg A, Van Horn L, Garside D,
Chan Q.
Association of dietary supplement
use with specific micronutrient intakes among middle-aged American
men and women: The INTERMAP Study.
J Am Diet Assoc. 2005;105:
1106-1114.
Radimer K, Bindewald B, Hughes J, Ervin B, Swanson C, Picciano
MF.
Dietary supplement use by US adults: Data from the National
Health and Nutrition Examination Survey, 1999-2000.
Am J Epidemiol.
2004;160:339-349.
De Jong N.
Demographic and lifestyle characteristics of functional
food consumers and dietary supplement users.
Br J Nutr. 2003;89:
273-281.
Foote JA, Murphy SP, Wilkens LR, Hankin JH, Henderson BE, Kolonel
LN.
Factors associated with dietary supplement use among
healthy adults of five ethnicities: The Multiethnic Cohort Study.
Am J
Epidemiol. 2003;157:888-897.
Satia-Abouta J, Kristal AR, Patterson RE, Littman AJ, Stratton KL,
White E.
Dietary supplement use and medical conditions: the VITAL
study.
Am J Prev Med. 2003;24:43-51.
Beitz R, Mensink GB, Fischer B, Thamm M.
Vitamins—Dietary intake
and intake from dietary supplements in Germany.
Eur J Clin Nutr. 2002;56:539-545.
Troppmann L, Johns T, Gray-Donald K.
Natural health product use
in Canada.
Can J Pub Health. 2002;93:426-430.
Blendon RJ, DesRoches CM, Benson JM, Brodie M, Altman DE.
Americans’ views on the use and regulation of dietary supplements.
Arch Intern Med. 2001;161:805-810.
Balluz LS, Kieszak SM, Philen RM, Julinare J.
Vitamin and supplement
use in the United States: Results from the third National Health
and Nutrition Examination Survey.
Arch Fam Med. 2000;9:258-262.
Messerer M, Johansson SE, Wolk A.
Sociodemographic and health
behaviour factors among dietary supplement and natural remedy
users.
Eur J Clin Nutr. 2000;55:1104-1110.
Ervin RB, Wright JD, Kennedy-Stephenson J.
Use of dietary supplements
in the United States, 1988-94.
Vital Health Stat 11. 1999;244: i-iii, 1-14.
Kirk SF, Cade, JE, Barrett JH, Conner M.
Diet and lifestyle characteristics
associated with dietary supplement use in women.
Public Health Nutr. 1999;2:69-73.
Nayga RM, Reed DB.
Factors associated with the intake of dietary
supplements.
Fam Econ Nutr Rev. 1999;12:43-48.
Lyle BJ, Mares-Perlman JA, Klein BE, Klein R, Greger JL.
Supplement users differ from nonusers in demographic, lifestyle, dietary and health characteristics.
J Nutr. 1998;128:2355-2362.
Patterson RE, Neuhouser ML, White E, Hunt JR, Kristal AR.
Cancer related behavior of vitamin supplement users.
Cancer Epidemiol Biomarkers Prev. 1998;7:79-81.
Eliason BC.
Dietary supplement users: Demographics, product use, and medical system interaction.
J Am Board Fam Pract. 1997;10:265-271.
Houston DK, Johnson MA, Daniel TD, Poon LW.
Health and dietary characteristics of supplement users in an elderly population.
Int J Vitam Nutr Res. 1997;67:183-191.
Slesinski MJ, Subar AF, Kahle LL.
Dietary intake of fat, fiber and other nutrients is related to the use of vitamin and mineral supplements in the United States: The 1992 National Health Interview Survey.
J Nutr. 1996;126:3001-3008.
Looker A, Sempos, CT, Johnson C, Yetley EA.
Vitamin-mineral supplement use: Association with dietary intake and iron status of adults.
J Am Diet Assoc. 1988;88:808-814.
Tippett KS, Cypel, YS, eds.
Design and Operation: The Continuing Survey of Food Intakes by Individuals
and the Diet and Health Knowledge Survey, 1994-96.
Beltsville, MD: US Department of Agriculture,
Agriculture Research Service; 1988. Nationwide Food Surveys Report No. 96-1.
USDA Database of Vitamin A (mcg RAE) and Vitamin E (mg AT) for
National Health and Nutrition Examination Survey 1999-2000.
Beltsville, MD: Agricultural Research Service, Food Surveys Research Group; 2006.
Quinlivan EP, Gregory JF.
Effect of food fortification on folic acid intake in the United States.
Am J Clin Nutr. 2003;77:221-225.
Lewis CJ, Crane NT, Wilson DB, Yetley EA.
Estimated folate intakes: Data updated to reflect food fortification, increased bioavailability, and dietary supplement use.
Am J Clin Nutr. 1999;70:198-207.
Food standards; amendment of standards of identity for enriched grain products to require addition of folic acid, final rule. 61
Federal Register 8781-8897 (1996).
Food additives permitted for direct addition to food for human consumption;
folic acid (folacin), final rule. 61
Federal Register 8797-8807 (1996).
National Center for Health Statistics.
National Health and Nutrition Examination Survey 1999-2000 Dietary Supplement Data Release.
http://www.cdc.gov/nchs/about/major/nhanes/quest99_00.htm
Institute of Medicine, Food and Nutrition Board.
Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc.
Washington, DC: National Academies Press; 2001.
Institute of Medicine, Food and Nutrition Board.
Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium and Carotenoids.
Washington, DC: National Academies Press; 2000.
Institute of Medicine, Food and Nutrition Board.
Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline.
Washington, DC: National Academies Press; 2000.
Suitor CW, Bailey LB.
Dietary folate equivalents: Interpretation and application.
J Am Diet Assoc. 2000;100:88-94.
Carriquiry AL.
Assessing the prevalence of nutrient inadequacy.
Public Health Nutr. 1999;2:23-33.
Nusser SM, Carriquiry AL, Dodd KW, Fuller WA.
A semiparametric transformation approach to estimating usual daily intake distributions.
J Am Stat Assoc. 1996;91:1440-1449.
Institute of Medicine, Food and Nutrition Board.
Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride.
Washington, DC: National Academies Press; 1997.
US Department of Agriculture, US Department of Health and Human
Services.
Nutrition and Your Health: Dietary Guidelines for Americans. 3rd ed. 1990.
ashington, DC: Home and Garden Bulletin No. 232.
Choumenkovitch SF, Selhhub J, Wilson PWF, Rader JI, Rosenberg
IH, Jacques PF.
Folic acid intake from fortification in United States exceeds predictions.
J Nutr. 2002;132:2792-2798.
Honein MA, Paulozzi LJ, Mathews TJ, Erickson JD, Wong LC.
Impact of folic acid fortification of the US food supply on the occurrence of neural tube defects.
JAMA. 2001;285:2981-2986.
Moshfegh AM, Goldman JD, Cleveland L.
What We Eat in America, NHANES 2001-2002:
Usual Nutrient Intake from Food Compared to Dietary Reference Intakes.
Washington, DC: US Department of Agriculture, Agricultural Research Service; 2005.
Ma J, Betts NM.
Zinc and copper intakes and their major food sources for older adults in the 1994-96 Continuing Survey of Food Intakes by Individuals (CSFII).
J Nutr. 2000;133:2838-2843.
Bales CW, DiSilvestro RA, Currie KL, Plaisted CS, Joung H, Galanos
AN, Lin PH.
Marginal zinc deficiency in older adults: Responsiveness of zinc status indicators.
J Am Coll Nutr. 1994;13:455-462.
Feskanich D, Singh V, Willett WC, Colditz GA.
Vitamin A intake and hip fractures among postmenopausal women.
JAMA. 2002;287:47-54.
Promislow JHE, Goodman-Gruen D, Slymen DJ, Barrett-Connor E.
Retinol intake and bone mineral density in the elderly: The Rancho Bernardo study.
J Bone Miner Res. 2002;17:1349-1358.
Melhus H, Michaelsson, K, Kindmark A, Bergstrom R, Holmberg L,
Mallmin H, Wolk A, Ljunghall S.
Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk
of hip fracture.
Ann Intern Med. 1998;129:770-778.
Carriquiry AL.
Estimation of usual intake distributions of nutrients and foods.
J Nutr. 2003;133(suppl):601S-608S.
Wold RS, Lopez ST, Yau L, Butler LM, Pareo-Tubbeh SL, Water DL,
Garry PJ, Baumgartner RN.
Increasing trends in elderly persons’ use of nonvitamin, nonmineral dietary supplements and concurrent use of
medications.
J Am Diet Assoc. 2005;105:54-63.
Radimer KL, Subar AF, Thompson FE.
Nonvitamin, nonmineral dietary supplements: Issues and findings from NHANES III.
J Am Diet Assoc. 2000;100:447-454.
Murphy, SP.
Collection and analysis of intake data from the intergrated survey.
J Nutr. 2003;133(suppl):585S-589S.
Dwyer J, Picciano MF, Raiten DJ, Members of the Steering Committee,
National Health and Nutrition Examination Survey.
Collection of food and dietary supplement intake data: What We Eat in America - NHANES.
J Nutr. 2003;133(suppl):590S-600S.
Return to NUTRITION
Return to SENIOR CARE
Since 8–01–2017
|