That's not PUFA's only problem, but there will never be long term studies because too many variables can occur. The only thing that a "whole food" PUFA source can provide is vitamin e, which saturates to some extent the unsaturated fat. Maybe the niacin too. Though, it's not clear to what extent it protects, and I would go so far as to say not very much at all. It would still serve in your best interest to keep PUFA very low in favor of saturated fat, so that at least the ratio would help along with the vitamin e.
You know, Neckhammer, why many older societies didn't have thyroid issues? Traces of thyroid was found in nearly every part of the animal, and they ate the glands, before meat started getting tightly regulated. I would say it's probably natural for everyone to be taking desiccated thyroid gland unless they're consuming thyroid glands themselves.
Longing is the agony of the nearness of the distant