Association of DNA damage with vitamin D and hair heavy metals of obese women

Abstract

Background: Obesity has been linked to DNA damage. The modifiable risk factors may modulate the impact of obesity on DNA damage. Objective: This study aimed to assess DNA damage and its association with dietary nutrient, serum 25-hydroxyvitamin D (25(OH)D) and concentration of hair heavy metals of obese and non-obese women. Method: A case-control study was conducted involving 134 women aged between 20 to 50 years. Serum 25(OH)D, fasting glucose, and lipid profile were assessed. Indicators of DNA damage such as percentage of tail DNA, tail moment, tail olive moment, tail intensity and tail length were measured using an alkaline-Comet assay.Concentrations of hair heavy metals were quantified using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Participants' daily energy, macro, and micronutrient intake were collected using the Food Frequency Questionnaire (FFQ). Results: Mean values of 25(OH)D was 31.8 ± 0.9 nmol/L. Majority of participants (96.3%) were 25(OH)D (<50 nmol/L) deficient. The mean BMI was 26.3 ± 0.5 kg/m 2 . Half of the participants (50.7%) have a high frequency of DNA strand breaks.Mean concentration of hair heavy metals (mg/kg) were 0.1 ± 0.03 (arsenic), 1.0 ± 0.4 (mercury), 2.8 ± 0.8 (lead), 0.2 ± 0.1 (cadmium) and 6.2 ± 0.4 (chromium). There was no significant difference for the mean of 25(OH)D, indicators of DNA damage, concentrations of hair heavy metals and dietary nutrients between obese and non-obese groups (p >0.05). Obese women with 25(OH)D level of ≥ 31nmol/L had a significantly lower tail moment (p=0.029) and tail olive moment (p=0.031); thus, indicating less DNA damage. Additionally, obese women with hair chromium concentration of ≥5.88 mg/kg had a significantly higher tail moment (p=0.047), indicating more DNA damage. Conclusion: DNA damage among obese women correlated with serum 25(OH)D and hair chromium.