My Mom started on Vitamin C, and what do you know --she all of the sudden started having heart trouble (beating 2 fast). I told her to please stop taking it for a while until she could consult a specialist. I know it was not just the C , at least I am really certain because she was also cooking with cast iron and also eating some really fresh deer. In my eyes she had too much iron all of the sudden and being as our family has the iron overload..she just got a GOOD dose. She has cut down on the cast iron cooking and the C so she is better now! She put the deer back too. Mellow with bland for a while! Lord knows if she was to keep eating that deer, and all that she was doing ...she would probably be the mayor of this town! EEEEEYYYYAAA she was getting energetic!