Don’t take tablets. They are nearly useless. Capsules and gelcaps are best. Don’t take multis, take the vitamins you decide you need, like C and D perhaps, or magnesium. You can easily test your D levels and adjust your personal dose.
And I’d be wary about supplementing iron right now as some new research is being discussed... Detriments of iron even that in “enriched” foods. At least read about it, as this is something new to worry about,
http://freetheanimal.com/2015/06/enrichment-theory-everything.html
Yes, capsules and gelcaps are absorbed the best. Yes.
Iron is usually only suggested if the person is anemic. Simple blood test can reveal it. But they still need to get to the source of the anemia, either it’s chronic (body not making enough blood cells) or specific (ulcer, bleeding inside somewhere)...
Regarding low iron. It’s rarely a problem with men. Also, if you are taking large does of C you will have much more efficient absorption of iron which can be a problem.
Some years ago my doctor had me on large doses of C. But my blood work showed my iron levels were too high (not good), so he said I had to either back off on the C or go give blood regularly.
I had a doctor tell me that 80-90% of pill vitamins pass out through urine, and that for the most part the industry was a scam.
Need extra iron, eat a rare steak every once in a while. Doc told me that’s why when they dropped my blood in that blue liquid it darn near cracked the bottom of the vial it sunk so fast.