Although iron is the most abundant metal in our body, traces of gold can be found in the human body in places such as the brain, heart, blood, and joints. If pure gold is collected in a human body weighing 70 kg, it can be up to 0.2 milligrams of gold. Although a high level of gold in our blood can cause toxicity, scientists have determined that gold does serve a function in maintaining the health of our joints in a small amount.