Whole-body phase angle as a non-invasive indicator of low-grade inflammation in generally healthy adults

Chronic low-grade inflammation contributes to metabolic and cardiovascular disease yet assessing relevant biomarkers can be costly and invasive. Whole-body phase angle (PhA), derived from bioelectrical impedance analysis (BIA), provides a simple, non-invasive marker of cellular health, but its association with biomarkers of inflammation and insulin resistance in generally healthy adults remain unclear. We aimed to evaluate associations between whole-body PhA and biomarkers of inflammation and insulin resistance in a sample of generally healthy adults, while controlling for relevant covariates.

Seventy-seven men and women (mean ± SD: age 52.1 ± 10.9 y; body mass index 25.8 ± 4.3 kg/m²) were enrolled in this cross-sectional study. PhA was measured using multifrequency BIA, and inflammatory and insulin resistance biomarkers were measured by fasting blood draw. Associations were assessed using multivariable linear regressions with adjustments for age, waist circumference, height, moderate-to-vigorous physical activity (MVPA), and sedentary behavior (SB). In the fully adjusted model, a higher PhA was associated with lower levels of C-reactive protein (β = -0.311, p = 0.043), adiponectin (β = -0.271, p = 0.031), and leptin (β = -0.427, p < 0.001), and a higher adiponectin-leptin ratio (β = 0.251; p = 0.010). No significant associations were observed with interluekin-6, tumor necrosis factor-alpha, or insulin resistance biomarkers (p > 0.05).

These findings suggest that PhA may be a promising non-invasive marker of low-grade inflammation in adults.