Heme iron and its link to oxidative stress has been re-evaluated over time.

Vegetables contain non-heme iron (Fe 3+), which is reduced to (Fe 2+) by the body on demand for absorption. In contrast, heme iron is already in its reduced state (Fe 2+). Because of its high bioavailability excess heme iron reacts with peroxides to produce highly reactive free radicals (Fenton reaction).

You can keep on potatoes safely.