Iron is essential for health, but it also extremely dangerous in excess. And unless someone is losing iron from menstruation or some other form of blood loss iron can build up in the body to dangerous levels. Under normal circumstances the amount of iron derived from diet is not sufficient to cause problems. When people supplement with pills or products like black strap molasses the risk is increased. People should not supplement with iron unless they are certain they are iron deficient anemic, or are losing blood in some manner. If someone recommends iron supplementation without taking these factors in to account RUN!!!  Recommending iron supplementation without knowing someone's medical history is very dangerous and shows a clear ignorance of how the body works. There are conditions, such as hemochromotosis, where iron is already built up to dangerous levels. And these people need to avoid all the iron they possibly can.

Excess iron can put a strain on the heart, liver, endocrine system,  can cause joint damage (arthritis), damage to other cells,  diabetes, cancer, arrhythmias, hypogandism, bronzing of the skin, fatigue, weakness, depression, weight loss,  etc.  Many dangerous bacteria also thrive on excess iron levels.

Here are some links to information on hemochromotosis and iron overload symptoms:

http://www.excessiron.com/excess-iron-symptoms.jsp

http://www.cdc.gov/ncbddd/hemochromatosis/symptoms.htm

http://www.ironoverload.org/brain.html

http://www.irondisorders.org/disorders/Acquired.asp

http://hcvadvocate.org/hepatitis/factsheets_pdf/Iron%20overload.pdf