If you're a man, you can give blood to get this effect. I believe there was a study linking this to a decline in diabetes risk (or something like that).

If you're a man you'd use leeches.

Or periodic woodworking accident.

Or combat.

Excess iron appears to be more of a risk factor for heart disease than diabetes. This is suspected as a reason why pre-menopausal women have a lower risk of heart attack than men and post-menopausal women. This is still an area of active research and not really proven.

Yes, that, too. I was thinking of this, but I think they're all closely related. And hey, even if the science doesn't pan out, you've still probably helped someone out with your donation.

https://www.nature.com/articles/d42473-018-00382-9

I am male and have the opposite issue. I become anemic without supplements. There seems to be some correlation with autism and low iron/b12.

I take Floradix, which is a German-made liquid made from vegetables and yeast. It has probably saved my life, because without it I become lethargic then severely depressed.

I joke that I'm a vampire and it is my human blood substitute that I take so I don't have to feed on people.

For this reason men's multivitamins typically don't include iron.