{Reference Type}: Journal Article
{Title}: Associations of 24 h urinary excretions of α- and γ-carboxyethyl hydroxychroman with plasma α- and γ-tocopherol and dietary vitamin E intake in older adults: the Lifelines-MINUTHE Study.
{Author}: Zhu Y;Frank J;Riphagen IJ;Minović I;Vos MJ;Eggersdorfer ML;Navis GJ;Bakker SJL;
{Journal}: Eur J Nutr
{Volume}: 61
{Issue}: 7
{Year}: Oct 2022
{Factor}: 4.865
{DOI}: 10.1007/s00394-022-02918-8
{Abstract}: <B>BACKGROUND: </B>Urinary metabolites of vitamin E, i.e., α- and γ-carboxyethyl hydroxychroman (α- and γ-CEHC), have gained increasing attention and have been proposed as novel biomarkers of vitamin E intake and status. However, there are insufficient data on the relationship of plasma α-tocopherol and γ-tocopherol and dietary vitamin E intake with 24 h urinary excretions of α- and γ-CEHC.<BR><B>OBJECTIVE: </B>We aimed to (1) investigate the associations of urinary α- and γ-CEHC/creatinine ratios and 24 h urinary excretions of α- and γ-CEHC with plasma α- and γ-tocopherol, respectively; (2) investigate the associations of urinary α- and γ-CEHC/creatinine ratios and 24 h urinary excretions of α- and γ-CEHC with dietary vitamin E intake, and we hypothesize that 24 h urinary excretions of α- and γ-CEHC will better correlate with vitamin E intake than urinary α- and γ-CEHC/creatinine ratios.<BR><B>METHODS: </B>24 h Urine and plasma samples were collected from 1519 participants (60-75 years, male: 50%) included in the Lifelines-MINUTHE Study for the assessments of urinary α- and γ-CEHC/creatinine ratios and 24 h urinary excretions of α- and γ-CEHC, and plasma α- and γ-tocopherol. Among those participants, dietary vitamin E intake data from 387 participants were available from an externally validated Flower-Food Frequency Questionnaire (FFQ). The associations of plasma α- and γ-tocopherol, dietary vitamin E intake, with urinary α- and γ-CEHC were assessed using multivariate linear regressions.<BR><B>RESULTS: </B>24 h Urinary excretion of α-CEHC (median (IQR): 0.9 (0.3-2.4) µmol) was less than that of γ-CEHC (median (IQR): 1.5 (0.5-3.5) µmol). After adjustment for covariates, we found that 24 h urinary α-CEHC excretion and urinary α-CEHC/creatinine ratio were both positively associated with plasma α-tocopherol (std.beta: 0.06, p = 0.02; std.beta: 0.06, p = 0.01, respectively). Furthermore, the sum of 24 h urinary α- and γ-CEHC excretions was positively associated with dietary vitamin E intake (std.beta: 0.08; p = 0.03), whereas there was no relation between urinary α- and γ-CEHC/creatinine ratios and vitamin E intake. No association was observed neither between plasma α- and γ-tocopherol and dietary vitamin E intake, nor between urinary γ-CEHC and plasma γ-tocopherol.<BR><B>CONCLUSIONS: </B>Our study confirmed our hypothesis that 24 h urinary α- and γ-CEHC excretions would be a better marker for dietary vitamin E intake than urinary α- and γ-CEHC/creatinine ratios. Considering that both 24 h urinary α- and γ-CEHC excretions and α- and γ-CEHC/creatinine ratios were also associated with plasma α-tocopherol status, we suggest that 24 h urinary α- and γ-CEHC excretions could be used to assess overall vitamin E status.