The Association of Mercury and ALT with Obesity in Korean Adults Using Data from the Korea National Health and Nutrition Examination Survey for 11 Years (KNHANES 2005, 2008–2017)

Abstract

The association between heavy metals in the blood and obesity has been examined in many studies. However, inconsistencies have been observed in the results of these studies. The present study was conducted using data from 119,181 participants of the Korea National Health and Nutrition Examination Survey (KNHANES) for 11 years in 2005 and between 2008 and 2017. The subjects with missing heavy metal blood tests, health interview data, and health examination data were excluded from the study. The study population comprised 1,844 individuals (972 men, and 872 women) who were eligible for inclusion. It was found that obesity and abdominal obesity were associated with an increase in both blood mercury (P < 0.001) and alanine aminotransferase (ALT) (P < 0.001). After adjusting the confounding factors, those with concurrent high levels of ALT and the highest tertile of mercury showed an increased risk of obesity (odds ratio 4.46, 95% confidence interval 2.23–8.90, P < 0.001) as well as abdominal obesity (odds ratio 5.36, 95% confidence interval 2.57–11.17, P < 0.001). The interrelationship of mercury and ALT with the parameters of body mass index (P for interaction = 0.009) and waist circumference (P for interaction = 0.012), respectively, have been observed to be significant, suggesting that the reciprocal relationship could contribute to obesity and abdominal obesity.