Conditions that cause hair loss

I have heard hypothyroidism, heavy metal, excess estrogen and diabetes can all cause hair loss in men. Can you let me know technically how it caues hair loss? And if you have any of these conditions how to limit the hair loss until you address the health issue? Is it these conditions cause deficienices that are needed for healthy head of hair?

If so what deficienices?

Can ulcers/bacteria/yeast cause hair loss - if so how?

Thanks