Personally, I think she's bonkers. No offense, but there's lots of things about chocolate that mean we shouldn't eat too much of it that are completely common knowledge, like the sugar can play havoc with your blood sugar levels, and the milk fat can make you gain weight. I reckon that for your friend to have eaten enough chocolate for the relatively low copper levels in the choclate to raise to toxic levels in her body, she'd have to eat enough that her blood sugar levels would be off the charts and she'd be obese - in which case, I think that it's a much more likely possibility that her health problems are related to bad diet in general - not chocolate.
Hi y'all, Copper levels can become excessive, but not by eating chocolate alone. The contraceptive pill is a big contributer to raised copper levels, exposure to copper piping from water supplies is another. Sometimes after pregnancy, copper levels don't fall as they should without nutritional help.
Hair analysis can help identify mineral imbalances but try www.nutricentre.co.uk for help and advice if excess copper levels concern you. www.healthy.net is another great site for answers, also www.wddty.com can shed light on a lot of baffling stuff, supplements can help any situation like this, but get some advice
good luck