Thanks for sharing this rather surprising observation, Mohsin. Yes, that's "only" anecdotal evidence, but you could solidify it by retaking the supplement, and monitoring whether your blood pressure increases again. BUT: Don't consider this a recommendation to follow. Keeping your blood pressure down is more important than proving your observation!

You also put your finger on one issue that has remained unclear: are daily doses above the 800IU limit safe in the long-run? We don't know yet.