Background: Pakistan exhibits a high global prevalence of vitamin D deficiency (78%) and excessive tea consumption patterns. Tea contains polyphenols and tannins that may interfere with mineral absorption through chelation mechanisms. This study aimed to determine the effects of excessive tea consumption on serum calcium and vitamin D levels among citizens of Nawabshah, Pakistan.
Methods: This cross-sectional study was conducted in Nawabshah from January to June 2024. A total of 344 adults aged 18-40 years were recruited using convenience sampling and classified into three groups based on daily tea consumption: 1-2 cups (n=58), 3-4 cups (n=50), and ≥5 cups (n=236). Serum calcium was measured using ethylene-diamine-tetra-acetic acid titration, and vitamin D levels were determined using enzyme-linked immunosorbent assay—statistical analysis employed one-way analysis of variance and independent t-tests with Bonferroni correction.
Results: Serum calcium levels decreased significantly across consumption groups: 8.36±0.68 mg/dL (1-2 cups), 7.46±0.72 mg/dL (3-4 cups), and 7.08±0.81 mg/dL (≥5 cups) (P<0.001). Vitamin D levels similarly declined: 20.2±8.4 ng/mL, 18.9±7.8 ng/mL, and 13.9±6.2 ng/mL, respectively (P<0.001). Hypocalcemia prevalence increased from 46.6% to 94.9% across groups, while vitamin D deficiency increased from 48.3% to 94.9%.
Conclusions: Excessive tea consumption demonstrates a significant dose-dependent inverse relationship with serum calcium and vitamin D levels. Healthcare providers should counsel patients about optimal tea consumption patterns to prevent mineral deficiencies in populations with endemic vitamin D insufficiency.
ISSN-online 2360-2473 / ISSN-print 1223-0472
