Penalized Regression Approach for Identifying the Risk Factors of Obesity and Underweight Among Children in North India

Obesity and underweight among children are major global public health problems driven by both known and emerging risk factors such as toxic chemicals. Considering this, a cross-sectional observational study was carried out to investigate the association between metallic and biochemical profiles and environmental risk factors among North Indian children. A total of 301 children between the ages of 6 and 16 years were enrolled and classified into non-obese (n = 101), obese (n = 100), and underweight (n = 100) groups according to their BMI from rural and urban areas. Various data validation techniques were applied, followed by binary logistic regression using penalized (LASSO) regression. A significant positive association was observed among obese children for fasting state serum glucose, whole blood arsenic, recently painted or pasted wallpaper in the house, and fish-eating habits. A positive association was found between non-fasting state serum levels of TSH, glucose, hs-CRP, and creatinine among obese children, while a negative association with obesity was observed for whole blood Pb, Cd, U, and serum magnesium. Similarly, underweight children were found to belong to an upper-lower sociodemographic class; living near dust/major roads/waste, and using plastic lunch boxes were negatively associated. A constant positive association was observed among obese children in both fasting and nonfasting states for those with eating habits of consuming fried foods ≥ 4 times a week. This study confirms the positive association of glucose, thyroid-stimulating hormone, and hsCRP as metabolic risk factors for obesity. It identifies whole blood arsenic levels as a potential risk factor and highlights various lifestyle and household aspects in underweight children. Additionally, it supports the use of penalized regression as an effective method for identifying emerging risk factors for obesity and underweight by investigating diverse exposure sources.