Is spirulina okay for thyroid?

Worthless: Despite all the hype and claims that it heals everything, most physicians see no benefit. It's bacteria / blue-green algae that form pond scum. Like everything else that has ever been alive, they contain biomolecules but despite the fact that this stuff has been around for decades, there is zero real work showing benefit. An evidence-based holist is your best guide if you're interested in this.