Tattoos have become so popular that it’s leading to concerns about their safety. Each prick delivers an ink into the dermis (the layer of skin that lies below the epidermis), which is populated with blood vessels and nerves. Once inserted into the dermis, not all ink stays put. Researchers have found that potentially toxic metals from tattoo ink circulates in the immune system, staining lymph nodes. But more research is needed to determine whether this is actually a bad thing. So, before you get that tattoo ink inserted into your skin, do a little research for yourself and make an informed decision.

Although there's been little study of about the effects of tattoos on human health, tattoo pigments are picked up as "foreign bodies" by the body's immune system and are then stored in the skin and lymph nodes. 

Your lymphatic system is incredibly important and failure to maintain it may serve to weaken your immune system.