ok that is good information but lets not hit the panic button here about iron and vitamin c. vitamin c did not cause your situation, excess iron consumption caused it.
iron overload as a medical condition, is usually genetic. yes vitamin c is generally contraindicated for people with the condition known as hematochromatosis. but keep in mind these people have to give blood on a regular basis to keep their iron levels down, regardless of their vitamin c intake - and their bodies still require vitamin c, regardless of its effect on iron absorption.
however men who do not have this genetic predisposition can still accumulate an undesirably high level of iron over time (by middle age) as appears to be the case here, and as illustrated by your example. as opposed to women who are protected via menstrual bleeding.
maybe my advice was not appropriate without the proper context. since you can drive your iron to high levels just through diet and not related to vitamin c intake, which appear to be what happened here, adding vitamin c to a high iron diet would not be advisable. vitamin c binds well to iron which could either help leach it from your body or increase its absorption ... if iron intake continues at high levels.
given he wants to lower his iron levels, his first priority diet-wise should be to analize and reduce his iron intake. if that is accomplished the vitamin c should assist normalizing his levels. i will tell you this, if plasma iron levels are high you will want to be on plenty of antioxidants. nutritional chelators, of which i believe garlic qualifies, would also be of merit. EDTA is also available in oral form.
if you go here:
http://www.nlm.nih.gov/medlineplus/druginfo/uspdi/202071.html
scroll to the bottom of the page you will see under certain circumstances vitamin c is
used to help address iron overload when used in combination with other substances. probably chelators.
if you go here:
http://www.vitamincfoundation.org/faqdocs.html
scroll down the page, you will see some different doctors opinons vs. the orthodox medical viewpoint
giving blood is certainly the most effective method to reduce your iron levels. high iron levels are not healthy and more people should probably be tracking this in their blood screenings.