Dietary selenium intake by men and women in high and low selenium areas of Punjab

Abstract

Objective: To determine the selenium intake of adults residing in high and low selenium areas of rural Punjab.

Design: All food samples consumed by the subjects were collected and analysed for selenium content. Based on food intake data and selenium content of foods, the selenium intake of the subjects was calculated. Hair, fingernails and urine samples from a sub-sample of subjects were collected and analysed for selenium.

Setting: Three villages from the selenium-endemic area of Nawan Shahr District and two villages from the non-endemic area of Ludhiana District, Punjab, India, were covered.

Subjects: Forty families from each of the two areas, with one adult male and one adult female in the age range of 20-40 years, were surveyed. Thus a total of 80 men and 80 women constituted the study sample.

Results: In the selenium-endemic area, the average selenium intake of both men and women was more than nine times that in the non-endemic area and exceeded the maximum tolerable limit in more than 60% of men. Mean selenium content of the hair, nails and urine of both men and women was tens of times higher than in the non-endemic area.

Conclusions: High selenium intake in the endemic area resulted in high selenium content in the hair, nails and urine of men and women. In addition, clinical symptoms of selenium toxicity were also observed in some of the subjects. Selenium intake in the non-endemic area was marginally below the suggested value. Based on the study results, steps need to be taken to educate the public in the endemic area to avoid selenium toxicity.