For two decades, researchers in eastern Massachusetts watched where a woman lived quietly shape her heart's future — more reliably, in some ways, than her income or education ever could. A study tracking roughly 1,200 women from pregnancy into their fifties found that neighborhood disadvantage carved a measurable and lasting gap in cardiovascular health, one that widened precisely when women were most vulnerable: the years before menopause. The findings ask us to reckon with a quiet truth — that the street a person comes home to each night is itself a kind of medicine, or its absence.