Background: Non-traditional risk factors including low levels of magnesium and high levels
of uric acid have been associated with central obesity and cardiovascular disease.
Objective: To determine the association between waist circumference (WC) and non-traditional risk factors
such as magnesium, phosphorus, and uric acid in indigenous children living at high altitudes.
Methods: A total of 354 (166 M) indigenous school children, aged 9.6 + 2.3 years, were enrolled in a
cross-sectional study in November 2011. Central obesity was defined as WC ≥ 90th percentile according
to age and sex. Low magnesium and phosphorus levels were defined as serum magnesium <1.8
mg/dL and phosphorus <2.4 mg/dL. Hyperuricemia was defined as serum uric acid > 7 mg/dL.
Results: The prevalence of central obesity was 6.8% (24/354). None of the children had hyperuricemia
or low phosphorus levels. Hypoagnesemia was identified in 21.7% (57/263). There was a significant association
between WC (z-score) and magnesium (r-015), uric acid (r0.28), phosphorus (r-0.30), HOMAIR
(r0.49), triglycerides (r0.24), and HDL-C (r0.24). However, calcium, sodium, and potassium were
not significantly associated with WC. As z-WC quartiles increased magnesium and phosphorus levels
significantly decreased, whereas uric acid levels increased. Multiple linear regression analysis showed
that z-WC was associated significantly and directly with uric acid (B0.31), triglycerides (B0.004), and
HOMA-IR (B0.35); and inversely with magnesium (B-0.83) and phosphorus (B-0.25), adjusted for confounding
Conclusion: Our results indicate that central obesity was associated significantly and inversely with
magnesium and phosphorus and directly with uric acid in indigenous school children. Supplementation
with magnesium and/or phosphorus could prevent future cardiovascular disease. Prospective and randomized
studies should be performed to confirm these findings.