Selenium intakes in UK South Asian and Caucasian women: a longitudinal analysis

Abstract

Selenium (Se) is a trace mineral and component of selenoproteins known to be crucial for immune and thyroid function and reproduction (1) . Better Se status has also been linked to lower mortality, slower cognitive decline, reduced viral virulence and lower cancer risk (1) . Se status in the UK is believed to be low (1) . This study used data collected in the D-FINES (Vitamin D, Food Intake, Nutrition and Exposure to Sunlight in Southern England) study to investigate the Se intake of UK women by ethnicity and season. Eighteen-to eightyyear-old Caucasian (mean age = 49 years, n 248) and South Asian (mean age = 50 years, n 55) women completed a 4-d diet diary (including one weekend day) in summer, autumn, winter and spring (June 2006-May 2007. Food-portion size photographs were included to aid participant estimation. Data were analysed using Win Diets 2005.Median Se intakes in Caucasians were 37, 38, 39 and 37 mg/d in summer, autumn, winter and spring, respectively. Median intakes for South Asians in summer, autumn, winter and spring were 35, 30, 36 and 32 mg/d. The figures show that 80-90% of Caucasians and 83-95 % of South Asians did not meet the RNI (60 mg/d) in any season and, more worryingly, 60 % of Caucasians and 60-70% of South Asians did not meet the LRNI (40 mg/d). While there was little seasonal change in Caucasian intakes, the South Asians showed a trend for poorer intake in autumn than in the other seasons. There was little difference in the percentage of women not achieving the LRNI or RNI by ethnicity, but there was a trend for Asians to be slightly less likely to achieve them in all seasons. Data were energy adjusted to allow for differing nutrient requirements. As the data were skewed, log transformation was performed to allow analysis by parametric methods. Independent samples T-tests showed statistically significant (P £ 0.05) differences in energyadjusted Se intakes in autumn (t = 2.515, P = 0.012) by ethnicity, with South Asian women having a significantly lower intake. However, no difference was found in summer, winter or spring. Selenium intake (µg/d) in Less than LRNIThis study highlights the poor Se intakes in UK women and adds novel information about Se intake by season. While overall we found no clear evidence of an ethnic or seasonal difference in Se intake, there was a trend for lower Se intakes in South Asian than in Caucasian women, especially in the autumn. This seasonal trend reflects the findings of the National Diet and Nutrition Survey in elderly people where the lowest Se status was found in autumn (2) . Limitations of the study include the acknowledged difficulty in precisely measuring food intake and the high variability in the Se content of foods, which limits the accuracy of the food-composition database used. These results should ideally be confirmed by the measurement of plasma Se. Our finding that 60-70% of the women did not meet the LRNI for Se is a matter of public-health concern, given the association between low Se status and a range of chronic health conditions (1)...

A Review of Dietary Selenium Intake and Selenium Status in Europe and the Middle East

“…The number of women that had Se intakes below the LRNI or RNI was not significantly different in terms of ethnicity. Only in the South Asian women was a seasonal variation noted, with significantly lower Se intake in the autumn [ 20 ].…”

“…UK studies, including a broad range of population groups, identified a fairly consistent overall suboptimal Se status in this country based on the range of 90–100 μg/L to achieve maximum GPx expression [ 20 , 37 , 60 , 70 , 71 , 77 , 78 , 79 , 80 , 81 ]. Pre-term infants in the Hampshire area who had received parenteral nutrition and blood transfusions had significantly lower mean plasma Se levels that normalised by six months of gestation-corrected age.…”

“…It is generally recognised that Se intakes across Europe are low, reflecting inadequate soil levels, particularly in Eastern Europe. Se intake in the UK has declined since the 1970s, and previous government surveys [ 19 ] indicate low Se intake across a wide age range of the UK population (Caucasian and Asian) [ 20 ].…”

Nutrient Intake and Factors Influencing Eating Behaviors in Older Migrant Women Living in the United Kingdom

“…Low nutrient densities of retinol, vitamin D, magnesium, potassium, copper, selenium, and monounsaturated fatty acids were significantly lower than the recommendations. The few studies and national surveys assessing micronutrient intakes have also found low nutrient intakes of retinol, vitamin D and selenium, particularly in women from South Asian origin (Nelson et al 2007;Darling et al 2010;Mavroeidi et al 2010). Low levels of mono-unsaturated fats have also been reported among South Asians living in the UK (Garduno-Diaz and Khokhar 2014).…”

Diets of minority ethnic groups in the UK: influence on chronic disease risk and implications for prevention

“…The study also investigated selenium intakes of South Asian ( n = 55) and Caucasian women ( n = 248). South Asian women were found to consume less selenium compared with Caucasian women, while intakes for both groups were found to be below the LRNI (Darling et al . 2010), which is of concern as an adequate intake is important for immune and thyroid functions and reproduction (British Nutrition Foundation 2001).…”