*2.1. Study Population*

In this cross-sectional study, we used baseline nutrition surveys to calculate the mMDS from a total study base of 486 career firefighters (428 firefighters were recruited from the Indianapolis Fire Department's 44 stations and 58 from the Fishers, Indiana Fire Department's 6 stations) who consented to and enrolled in the ongoing study "Feeding America's Bravest": Mediterranean Diet-Based Interventions to change Firefighters' Eating Habits and Improve Cardiovascular Risk Profiles between 28 November 2016 and 16 April 2018 [34,39]. We excluded firefighters who did not complete baseline anthropometric measurements or if their biomarker indices were missing (Figure 1). Recruitment, consent, and study procedures were carried out by trained staff of the National Institute for Public Safety Health, who work regularly with both or the respective fire departments.

**Figure 1.** Flow chart for firefighters' sample selection. mMDS: modified Mediterranean Diet Score, FFQ: Food Frequency Questionnaire.
