Table of Contents

Locator Record

Title: Vitamins A, E, and Carotenoids (VITAEC_D )
Contact Number: 1-866-441-NCHS
Years of Content: 2005 - 2006
First Published: July, 2009
Revised: October, 2011
Access Constraints: None
Use Constraints: None
Geographic Coverage: National
Subject:Fat-soluble micronutrients
Record Source: NHANES 2005 - 2006
Survey Methodology: NHANES 2005 - 2006 is a stratified multistage probability sample of the civilian non-institutionalized population of the U.S.
Medium: NHANES Web site; SAS transport files

Component Description

The objectives of this component are:

  1. to provide data for monitoring secular trends in measures of nutritional status in the U.S. population;
  2. to evaluate the effect of people's habits and behaviors such as physical activity and the use of alcohol, tobacco, and dietary supplements on people's nutritional status; and
  3. to evaluate the effect of changes in nutrition and public health policies including welfare reform legislation, food fortification policy, and child nutrition programs on the nutritional status of the U.S. population.

These data will be used to estimate deficiencies and toxicities of specific nutrients in the population and subgroups, to provide population reference data, and to estimate the contribution of diet, supplements, and other factors to serum levels of nutrients. Data will be used for research to further define nutrient requirements as well as optimal levels for disease prevention and health promotion.

Eligible Sample

Participants aged 6 years and older who do not meet any of the exclusion criteria are eligible.

Description of Laboratory Methodology

Serum concentrations of vitamins A (retinol) and E (α and γ-tocopherol), two retinyl esters, and six carotenoids (alpha-carotene, trans-β-carotene, cis β-carotene, β-cryptoxanthin, combined lutein/zeaxanthin, trans-lycopene, and total lycopene) are measured using high performance liquid chromatography with photodiode array detection. A small volume (100 μL) of serum is mixed with an ethanol solution containing two internal standards- retinyl butyrate and nonapreno-beta-carotene (C45). The micronutrients are extracted from the aqueous phase into hexane and dried under vacuum. The extract is redissolved in ethanol and acetonitrile and is filtered to remove any insoluble material. An aliquot of the filtrate is injected onto a C18 reversed phase column and isocratically eluted with a mobile phase consisting of equal parts of ethanol and acetonitrile. Absorbance of these substances in solution is linearly proportional to concentration. Three wavelengths, approximately corresponding to absorption maxima, namely, 300, 325, and 450 nm, are simultaneously monitored and chromatograms are recorded.

Data Processing and Editing

Serum specimens were processed, stored, and shipped to the Division of Laboratory Sciences, National Center for Environmental Health, and Centers for Disease Control and Prevention for analysis. Detailed specimen collection and processing instructions are discussed in the NHANES LPM. Vials were stored under appropriate frozen (–30°C) conditions until they were shipped to National Center for Environmental Health for testing.

Twelve derived variables were created in this data file. The formula for their derivatization is as follows:

The vitamin A (retinol) results in μg/dL were converted into umol/L by multiplying by 0.03491.

The retinyl palmitate results in μg/dL were converted into umol/L by multiplying by 0.03491.

The retinyl stearate results in μg/dL were converted into umol/L by multiplying by 0.03491.

The vitamin E (α-tocopherol) results in μg/dL were converted into umol/L by multiplying by 0.02322.

The γ-tocopherol results in μg/dL were converted into umol/L by multiplying by 0.02402.

The α-carotene results in μg/dL were converted into umol/L by multiplying by 0.01863.

The trans-β-carotene results in μg/dL were converted into umol/L by multiplying by 0.01863.

The cis-β-carotene results in μg/dL were converted into umol/L by multiplying by 0.01863.

The β-cryptoxanthin results in μg/dL were converted into umol/L by multiplying by 0.01810.

The combined lutein/zeaxanthin results in μg/dL were converted into umol/L by multiplying by 0.01758.

The trans-lycopene results in μg/dL were converted into umol/L by multiplying by 0.01863.

The combined lycopene results in μg/dL were converted into umol/L by multiplying by 0.01863.

Laboratory Quality Assurance and Monitoring

The NHANES quality assurance and quality control (QA/QC) protocols meet the 1988 Clinical Laboratory Improvement Act mandates. Detailed QA/QC instructions are discussed in the NHANES Laboratory/Medical Technologists Procedures Manual (LPM). Read the LABDOC file for detailed QA/QC protocols.

There weren’t any changes to the laboratory, method, or site from 1999-2002, but the laboratory and method changed in 2003-2004 (see Analytical Note).

A detailed description of the quality assurance and quality control procedures can be found on the NHANES website.

Analytic Notes

NHANES Survey Design:

The analysis of NHANES laboratory data must be conducted with the key survey design and basic demographic variables. The Demographic file contains: Status Variables providing core information on the survey participant including examination status, Recoded Demographic Variables including age, gender, race etc., and Interview and Examination Sample Weight Variables and Survey Design Variables. The Questionnaire Data Files contain socio-economic data, health indicators, and other related information collected during household interviews. The Phlebotomy Examination file includes auxiliary information on duration of fasting, the time of day of the venipuncture, and the conditions precluding venipuncture. The Demographic, Questionnaire and Phlebotomy Examination files may be linked to the laboratory data file using the unique survey participant identifier SEQN.

Vitamins A, E, Carotenoids Limits of Detection:

 
Vitamin A/E/carotenoids
Limit of Detection (LOD) in micrograms/deciliter
 Analyte  SAS Variable  LOD(µg/dL)
 Serum vitamin A (Retinol)  LBXVIA  1.03
 Serum vitamin E (alpha-tocopherol)  LBXVIE  40.67
 Serum gamma-tocopherol  LBXGTC  10.72
 Serum alpha-carotene  LBXALC  0.7
 Serum trans-beta-carotene  LBXBEC  0.8
 Serum cis-beta-carotene  LBXCBC  0.7
 Serum beta-cryptoxanthin  LBXCRY  0.9
 Serum lutein/zeaxanthin  LBXLUZ  2.4
 Serum retinyl palmitate  LBXRPL  1.3
 Serum retinyl stearate  LBXRST  0.7
 Serum total lycopene  LBDTLY  1.0
 Serum trans-lycopene  LBXLYC  0.8

The note below will help you understand the change in laboratories. The Division of Environmental Laboratories at CDC in Atlanta, Ga performed the testing in 1999-2002 and 2005-2006. Craft Technologies performed the testing in 2003-2004.

Regression Analysis for 2001-2002 and 2003-2004 for Vitamins A, E, and Carotenoids:

In 2001-2002, Vitamins A, E and Carotenoids were analyzed using a HPLC method performed at CDC/NCEH. In 2003-2004, Vitamins A, E and Carotenoids were analyzed using a comparable HPLC method at Craft Technologies, Inc. (CTI) [See Lab 45 in NHANES 2003-2004 for method details]. Crossover studies between CDC/NCEH and CTI were done in early 2003 and late 2004 and differences existed between the methods for some analytes. The following Deming regression analyses were performed to compare data from 2001-2002 to 2003-2004:

Early 2003 Deming Regression Analysis for A/E/Carotenoids Y(CDC)=X(CTI) in μg/dL
Test n Y(CDC)=X(CTI)  r2 
Alpha-Carotene 100 y = 0.9734x + 0.1847 0.9944
Trans-Beta-Carotene 100 y = 1.0764x - 0.0248 0.9971
 Cis-Beta-Carotene 100 y = 0.8017x - 0.0372 0.9685
 Beta-Cryptoxanthin 100 y = 1.1359x - 0.2116 0.9945
 Gamma-Tocopherol 100 y = 1.0346x - 8.5749 0.9818
 Lutein/Zeaxanthin 99 y = 0.9321x + 0.1231 0.9455
 Trans-Lycopene 100 y = 1.0719x - 0.1817 0.9947
Retinyl Palmitate 100 y = 1.0245x + 0.5039 0.1988
Retinyl Stearate 97 y = 0.803x - 0.0048 0.9807
Vitamin A 100 y = 0.9406x - 0.1199 0.9887
Vitamin E 100 y = 0.9541x - 22.231 0.9941

Late 2004 Deming Regression Analysis for A/E/Carotenoids Y(CDC)=X(CTI) in μg/dL
Test n Y(CDC)=X(CTI)  r2 
Alpha-Carotene 99 y = 0.9989x + 0.2204 0.9768
Trans-Beta-Carotene 98 y = 1.0275x + 1.2976 0.9960
 Cis-Beta-Carotene 99 y = 0.7154x + 0.1344 0.9826
 Beta-Cryptoxanthin 98 y = 1.0824x - 0.056 0.9696
 Gamma-Tocopherol 98 y = 1.0306x - 5.523 0.9922
 Lutein/Zeaxanthin 99 y = 1.1082x - 1.602 0.9141
 Trans-Lycopene 98 y = 1.0971x + 0.0645 0.9737
Retinyl Palmitate 98 y = 0.7989x + 1.2106 0.8845
Retinyl Stearate 98 y = 0.7681x + 0.1483 0.9621
Vitamin A 99 y = 0.9806x + 0.2901 0.9934
Vitamin E 98 y = 0.93x + 22.614 0.9905

Combined Deming Regression Analysis for A/E/Carotenoids Y(CDC)=X(CTI) in μg/dL
Test n Y(CDC)=X(CTI)  r2 
Alpha-Carotene 199 y = 0.9837x + 0.2137 0.9877
Trans-Beta-Carotene 198 y = 1.0339x + 0.8812 0.9960
 Cis-Beta-Carotene 199 y = 0.7232x + 0.0879 0.9815
 Beta-Cryptoxanthin 198 y = 1.0958x - 0.0542 0.9793
 Gamma-Tocopherol 198 y = 1.029x - 6.287 0.9893
Lutein/Zeaxanthin 198 y = 1.0641x - 1.2402 0.9225
 Trans-Lycopene 198 y = 1.0852x - 0.0681 0.9849
Retinyl Palmitate 198 y = 0.8227x + 0.99 0.7603
Retinyl Stearate 195 y = 0.7881x + 0.0711 0.9675
Vitamin A 199 y = 0.9805x - 1.0069 0.9871
Vitamin E 198 y = 0.9397x + 1.649 0.9914

The combined regression was performed using crossover data from early 2003 and late 2004. The data user may wish to apply regression formulas to compare results from 1999-2000, 2001-2002, 2003-2004, and 2005-2006.

 

References

Codebook and Frequencies

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Both males and females 6 YEARS - 150 YEARS

LBXALC - Alpha-carotene (ug/dL)

Variable Name:
LBXALC
SAS Label:
Alpha-carotene (ug/dL)
English Text:
Alpha-carotene (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.5 to 96.5 Range of Values 7246 7246
. Missing 840 8086

LBDALCSI - Alpha-carotene (umol/L)

Variable Name:
LBDALCSI
SAS Label:
Alpha-carotene (umol/L)
English Text:
Alpha-carotene (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.009 to 1.798 Range of Values 7246 7246
. Missing 840 8086

LBXBEC - trans-Beta carotene (ug/dL)

Variable Name:
LBXBEC
SAS Label:
trans-Beta carotene (ug/dL)
English Text:
trans-Beta carotene (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.6 to 335 Range of Values 7254 7254
. Missing 832 8086

LBDBECSI - trans-Beta carotene (umol/L)

Variable Name:
LBDBECSI
SAS Label:
trans-Beta carotene (umol/L)
English Text:
trans-Beta carotene (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.011 to 6.241 Range of Values 7254 7254
. Missing 832 8086

LBXCBC - cis-Beta carotene (ug/dL)

Variable Name:
LBXCBC
SAS Label:
cis-Beta carotene (ug/dL)
English Text:
cis-Beta carotene (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.5 to 22.1 Range of Values 6616 6616
. Missing 1470 8086

LBDCBCSI - cis-Beta carotene (umol/L)

Variable Name:
LBDCBCSI
SAS Label:
cis-Beta carotene (umol/L)
English Text:
cis-Beta carotene (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.009 to 0.412 Range of Values 6616 6616
. Missing 1470 8086

LBXCRY - b-Cryptoxanthin (ug/dL)

Variable Name:
LBXCRY
SAS Label:
b-Cryptoxanthin (ug/dL)
English Text:
b-Cryptoxanthin (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.6 to 151 Range of Values 7195 7195
. Missing 891 8086

LBDCRYSI - b-Cryptoxanthin (umol/L)

Variable Name:
LBDCRYSI
SAS Label:
b-Cryptoxanthin (umol/L)
English Text:
b-Cryptoxanthin (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.011 to 2.733 Range of Values 7195 7195
. Missing 891 8086

LBXGTC - g-Tocopherol (ug/dL)

Variable Name:
LBXGTC
SAS Label:
g-Tocopherol (ug/dL)
English Text:
g-Tocopherol (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
14 to 1910 Range of Values 7217 7217
. Missing 869 8086

LBDGTCSI - g-Tocopherol (umol/L)

Variable Name:
LBDGTCSI
SAS Label:
g-Tocopherol (umol/L)
English Text:
g-Tocopherol (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.336 to 45.878 Range of Values 7217 7217
. Missing 869 8086

LBXLUZ - Lutein and zeaxanthin (ug/dL)

Variable Name:
LBXLUZ
SAS Label:
Lutein and zeaxanthin (ug/dL)
English Text:
Lutein and zeaxanthin (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1.7 to 111 Range of Values 7254 7254
. Missing 832 8086

LBDLUZSI - Lutein and zeaxanthin (umol/L)

Variable Name:
LBDLUZSI
SAS Label:
Lutein and zeaxanthin (umol/L)
English Text:
Lutein and zeaxanthin (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.03 to 1.951 Range of Values 7254 7254
. Missing 832 8086

LBXLYC - trans-Lycopene (ug/dL)

Variable Name:
LBXLYC
SAS Label:
trans-Lycopene (ug/dL)
English Text:
trans-Lycopene (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.6 to 110 Range of Values 7254 7254
. Missing 832 8086

LBDLYCSI - trans-Lycopene (umol/L)

Variable Name:
LBDLYCSI
SAS Label:
trans-Lycopene (umol/L)
English Text:
trans-Lycopene (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.011 to 2.049 Range of Values 7254 7254
. Missing 832 8086

LBXRPL - Retinyl Palmitate (ug/dL)

Variable Name:
LBXRPL
SAS Label:
Retinyl Palmitate (ug/dL)
English Text:
Retinyl Palmitate (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.9 to 26.5 Range of Values 6946 6946
. Missing 1140 8086

LBDRPLSI - Retinyl Palmitate (umol/L)

Variable Name:
LBDRPLSI
SAS Label:
Retinyl Palmitate (umol/L)
English Text:
Retinyl Palmitate (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.031 to 0.925 Range of Values 6946 6946
. Missing 1140 8086

LBXRST - Retinyl Stearate (ug/dL)

Variable Name:
LBXRST
SAS Label:
Retinyl Stearate (ug/dL)
English Text:
Retinyl Stearate (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.5 to 8.4 Range of Values 6698 6698
. Missing 1388 8086

LBDRSTSI - Retinyl Stearate (umol/L)

Variable Name:
LBDRSTSI
SAS Label:
Retinyl Stearate (umol/L)
English Text:
Retinyl Stearate (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.017 to 0.293 Range of Values 6698 6698
. Missing 1388 8086

LBXVIA - Vitamin A (ug/dL)

Variable Name:
LBXVIA
SAS Label:
Vitamin A (ug/dL)
English Text:
Vitamin A (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
8.6 to 251 Range of Values 7254 7254
. Missing 832 8086

LBDVIASI - Vitamin A (umol/L)

Variable Name:
LBDVIASI
SAS Label:
Vitamin A (umol/L)
English Text:
Vitamin A (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.3 to 8.762 Range of Values 7254 7254
. Missing 832 8086

LBXVIE - Vitamin E (ug/dL)

Variable Name:
LBXVIE
SAS Label:
Vitamin E (ug/dL)
English Text:
Vitamin E (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
312 to 5910 Range of Values 7254 7254
. Missing 832 8086

LBDVIESI - Vitamin E (umol/L)

Variable Name:
LBDVIESI
SAS Label:
Vitamin E (umol/L)
English Text:
Vitamin E (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
7.245 to 137.23 Range of Values 7254 7254
. Missing 832 8086

LBDTLY - Total (cis- and trans-)Lycopene (ug/dL)

Variable Name:
LBDTLY
SAS Label:
Total (cis- and trans-)Lycopene (ug/dL)
English Text:
Total (cis- and trans-)Lycopene (ug/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.7 to 175 Range of Values 7149 7149
. Missing 937 8086

LBDTLYSI - Total (cis- and trans-)Lycopene (umol/L)

Variable Name:
LBDTLYSI
SAS Label:
Total (cis- and trans-)Lycopene (umol/L)
English Text:
Total (cis- and trans-)Lycopene (umol/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.013 to 3.26 Range of Values 7149 7149
. Missing 937 8086