The County Health Rankings use four categories to measure people's health: health behavior, clinical care, social and economic factors and physical environment.
Compared to the state average of adult smokers, 19 percent, Arlington and Fairfax counties have a relatively low percentage of adult smokers with 12 percent and 13 percent, respectively.
However, both counties have higher excessive drinking rates than the state average. The state average for excessive drinking is 16 percent, whereas the average excessive drinking rate is 21 percent in Arlington and 20 percent in Fairfax.
Both Northern Virginia counties ranked better-than-average in the adult obesity subcategory. The state average for adult obesity is 28 percent, while it's 19 percent in Arlington and 24 percent in Fairfax.
The numbers show that education rates play a factor in how healthy a county is. Sixty-five percent of people in Virginia have attended some college. In Arlington, that number is 87 percent, and in Fairfax it is 79 percent.
Fairfax and Arlington also have a lower percentage of uninsured residents than the state average. While the state average is 14 percent, only 11 percent of Fairfax residents and 12 percent of Arlington residents are uninsured.
A surprising subcategory where the two Northern Virginia counties did not exceed the state average: mammograms. Arlington is even with the state average of 67 percent, and Fairfax is just behind with 66 percent.
More than 3,000 counties across the country and the District can use the County Health Rankings to compare how healthy their residents are. This is the third year for the rankings and they are published by the University of Wisconsin Population Health Institute and the Robert Wood Johnson Foundation (RWJF).