They're related phenomena. In general, sprawl (associated with car dependence) tracks with food deserts[1]. Reduce the sprawl, and you reduce the need for cars to access affordable, healthy food (and corresponding absence of access when people can't afford cars).
Edit: https://www.healthline.com/nutrition/food-deserts#locations-...
Concentration of the poor, and segregation are identified as the primary causes there. Not cars.