DSM highlights a new study: nearly a quarter of South Korean adults have deficient vitamin E status
The objectives of the study were to estimate intake and plasma concentration of each tocopherol, in order that a greater level of accuracy may be achieved in evaluating vitamin E status of Korean adults. Study results concluded that although vitamin E intakes of Korean adults were generally adequate according to the Korean Dietary Reference Intakes, 23% of the subjects in the current study were vitamin E deficient based on plasma α-tocopherol concentrations, and additional 67% had a plasma level in the suboptimal range. The results show that at 3.07mg/day, intakes of α-tocopherol; the form of vitamin E most preferentially absorbed in humans, are much lower than that reported in other countries. In comparison, Japanese adults reported a daily α-tocopherol intake of 6.6-7.1 mg2, and American adults indicated an α-tocopherol intake of 5.9-8.8 mg according to the 2003-2006 National Health and Nutrition Examination Survey (NHANES) US3.
Vitamin E deficiency and inadequate status may increase risk of several chronic diseases4, and studies have shown that inadequate vitamin E intake might be associated with risk of heart disease5,6, type II diabetes, and certain types of cancer7. Trials to investigate the benefits of vitamin E against symptoms associated with Alzheimer’s disease showed that vitamin E treated patients exhibited a slower functional decline, when compared to subjects that received the placebo8. Vitamin E is a powerful antioxidant, and plays an important role in preventing the peroxidation of lipids and oxidation of proteins, and can overcome the issue of fatty liver in certain patient groups. The European Commission has authorized an Article 13.1 health claim stating that “vitamin E contributes to the protection of cells from oxidative stress”.
As part of the study, blood samples from 106 healthy adults were taken, and the intake of a number of compounds, fatty acids and vitamin E was calculated. The Korean food composition table reports vitamin E contents in foods only as α-tocopherol equivalent (α-TE) without each tocopherol content, so the dietary intake and plasma concentration of each α-, β-, δ-, and γ-tocopherol in the study were estimated using alternative values. Dietary intakes of vitamin E were then compared with the Adequate Intakes (AIs) for Koreans9.
Results showed that 12.3% of all subjects consumed less vitamin E than the AI, and 89.6% had α-tocopherol levels that were less than 20 μmol/L; the concentration below which there is an increased risk of cardiovascular disease10,11.
James Bauly, Marketing Director Asia Pacific, DSM Nutritional Products Human Nutrition and Health, comments: “Vitamin E intakes of Korean adults are generally adequate compared with the Korean Daily Reference Intakes (DRIs). However, the α-tocopherol intake was lower than those of other countries, and if only α-tocopherol is considered, then the intake of many subjects in the present study may be inadequate. Further research regarding the bioavailability of tocopherols and tocotrienols in South Korea is needed to determine whether the current vitamin E unit in South Korea is appropriate. The study is another example that we cannot take adequate vitamin intake for granted even in apparently healthy or affluent populations, and highlights the importance of good, balanced nutrition, which may be complemented by a supplement if required.”
1) Young-Nam Kim, Yonn-Ok Cho, Nutrition Research and Practice 2015; 9 (2): 192-198.
2) Zou Y, Wang DH, Sakano N, Sato Y, Iwanaga S, Taketa K, Kubo M, Takemoto K, Masatomi C, Inoue K, Ogino K. Associations of serum retinol, α-tocopherol, and γ-tocopherol with biomarkers among healthy Japanese men. Int J Environ Res Public Health 2014;11:1647-60.
3) Bailey RL, Fulgoni VL 3rd, Keast DR, Dwyer JT. Examination of vitamin intakes among US adults by dietary supplement use. J Acad Nutr Diet 2012;112:657-663.e4.
4) The Korean Nutrition Society. Dietary Reference Intakes for Koreans. Seoul: The Korean Nutrition Society; 2010.
5) McCullough ML, Feskanich D, Stampfer MJ, Giovannucci EL, Rimm EB, Hu FB, Spiegelman D, Hunter DJ, Colditz GA, Willett WC. Diet quality and major chronic disease risk in men and women: moving toward improved dietary guidance. Am J Clin Nutr 2002;76:1261-71.
6) Singh U, Devaraj S, Jialal I. Vitamin E, oxidative stress, and inflammation. Annu Rev Nutr 2005;25:151-74.
7) Constantinou C, Papas A, Constantinou AI. Vitamin E and cancer: an insight into the anticancer activities of vitamin E isomers and analogs. Int J Cancer 2008;123:739-52.
8) Dysken MW, Sano M, Asthana S, Vertrees JE, Pallaki M, Llorente M, Love S, Schellenberg GD, McCarten JR, Malphurs J, et al. Effect of vitamin E and memantine on functional decline in Alzheimer disease: the TEAM-AD VA cooperative randomized trial. JAMA 2014;311:33-44.
9) The Korean Nutrition Society. Dietary Reference Intakes for Koreans. Seoul: The Korean Nutrition Society; 2010.
10) Riemersma RA, Wood DA, Oliver MF, Elton RA, Macintyre CC, Gey KF. Risk of angina pectoris and plasma concentrations of vitamins A, C, and E and carotene. Lancet 1991;337:1-5.
11) Singh RB, Ghosh S, Niaz MA, Singh R, Beegum R, Chibo H, Shoumin Z, Postiglione A. Dietary intake, plasma levels of antioxidant vitamins, and oxidative stress in relation to coronary artery diseasein elderly subjects. Am J Cardiol 1995;76:1233-8.