RE Hypothrodism, your best bet is to take an iodine suppliment like iodorol, not seaweeds. Thanks to industrialization and nuclear accidents there’s no source of clean seaweed. Plus even if seaweed was clean you’d need to eat so much to get enough to be effective.
Here’s a book I just read on iodine, look up on amazon: Lynne Farrow’s book The Iodine Crisis: What You Don’t Know About Iodine Can Wreck Your Life.
Until we get to the bottom of maca’s purported goitrogenic properties, taking maca on a hypo-thyroid couldn’t help you.
I believe the ancients did benefit from maca and so do some modern folks, but don’t we hear of symptoms that sound like anti-nutritive properties of maca affect some?
Just wanting to get to the bottom of this question.