You're right but this seems difficult to estimate. From the wikipedia* article:

> ... Despite this, there were no deaths caused by acute radiation syndrome. Given the uncertain health effects of low-dose radiation, cancer deaths cannot be ruled out. ...Predicted future cancer deaths due to accumulated radiation exposures in the population living near Fukushima have ranged in the academic literature from none to hundreds.

> ...For evacuation, the estimated number of deaths during and immediately after transit ranges from 34 to "greater than 50". The victims include hospital inpatients and elderly people at nursing facilities who died from causes such as hypothermia, deterioration of underlying medical problems, and dehydration. The old people and already sick, were more likely to be injured because of being relocated than damaged by radiation.

* https://en.wikipedia.org/wiki/Fukushima_nuclear_accident_cas...