Poster Topical Area: Vitamins and Minerals
Location: Hall D
Poster Board Number: 494
Objective: Some fat-soluble nutrients share transport mechanisms with circulating lipids and may be influenced by changes in these lipids in response to interventions like weight loss. The objective of this study is to determine the associations between changes in circulating fat-soluble nutrients and changes in blood lipids following intentional weight loss.
Methods: We conducted a secondary analysis of 94 overweight and obese, post-menopausal women who participated in a 20-week caloric-restriction weight loss intervention (Nicklas BJ, Am J Clin Nutr. 2009;89(4):1043-52). Study meals and a twice daily supplement that contained 500mg calcium, 500IU vitamin D, and 40ug phylloquinone were provided. Circulating concentrations of retinol, carotenoids, 25(OH)D, α-tocopherol, and phylloquinone were measured from blood samples obtained pre- and post-intervention. For this analysis, women were categorized into three sets of tertiles (T1, T2, T3) based on changes in total triglycerides (TG), LDL-C, and HDL-C. Analysis of variance was used to determine if changes in circulating fat-soluble nutrients differed across tertiles for a given lipid. If the overall F-test was significant after adjusting for multiple testing with a Bonferroni correction, individual tertiles were compared using Tukey's honestly significant difference test.
Results: Overall, women lost 12.1 ± 4.5 kg and circulating TG, HDL-C, and LDL-C declined (TG: -23.9mg/dl ± 39.9, LDL-C: -6.2mg/dl ± 18.2, HDL-C: -2.5mg/dl ± 7.4, respectively). Changes in plasma α-tocopherol differed across TG tertile (T1: -266μg/dL ± 580; T2: -21μg/dL ± 523; T3: 507μg/dL ± 743; ANOVA p<0.001, T3 significantly different from T1 and T2, p<0.004) and LDL-C tertile (T1: -181μg/dL ± 578; T2: -112μg/dL ± 462; T3: 508μg/dL ± 807; ANOVA p<0.001, T3 significantly different from T1 and T2, p<0.002). Changes in the other fat-soluble nutrients did not differ according to the change in TG, LDL-C, or HDL-C (all p >0.006).
Conclusion: With the exception of α-tocopherol, changes in blood lipids associated with intentional weight-loss did not correspond to changes in circulating fat-soluble nutrients in this group of post-menopausal women. The lack of association with most fat-soluble nutrients was surprising and warrants further investigation.
JM USDA HNRCA, Tufts University