I've seen that ad too, and at least half of them could throw out their BMI results. There was a large study in the UK that a much simpler to calculate indication of "good health" (an absence of diseases from NHS records) is a waist half of height, indicating the absence of visceral fat (not applicable with your medical condition though).

So you can go crazy with your curiosity , just click on anyone's name to open their profile, and see their height, many profiles with photos too. Depending on a person's question on this forum, I will check the height to be sure that their weight goals are realistic.