Figure 1.

Observational analysis and Mendelian randomization form the basis of the overall study design: (A) flowchart of the observational study; (B) flowchart of the MR analysis, along with the three key assumptions for Mendelian randomization: Assumption 1: the exposure is closely associated with the genetic variant; Assumption 2: the genetic variant is not associated with confounding factors; Assumption 3: the genetic variant affects the outcome only through the exposure of interest. NHANES: National Health and Nutrition Survey, MR: Mendelian randomization. The images were adapted from biorender.com under the terms of the Non-Commercial Use License.