I know calcium and iron should not be taken together. I believe a few hours at least between the two. As for eating I don't think there are any restrictions on if you can or cannot eat when taking iron. Alcohol and caffeine I think also can affect the absorption of iron.
on 3/13/20 9:52 am - WI
Take Iron at least 3 hours before or after Calcium. Do not take it with tea or coffee. The tannins interfere with absorption. Don't take it within 2 hours of any antacids.
You can take it with food to avoid stomach upset.