Hyperpigmentation or dark spots over the face appear when your skin stimulates excess production of melanin. (skindiseaseremedies.com)
Copper plays a role in a wide range of physiological processes including iron utilization, elimination of free radicals, the production of melanin and development of bone and connective tissue. (swoonfood.com)
She may be born with blue eyes (the eyes sometimes don't produce much — if any — melanin while the baby is in the womb), but after birth, light stimulates the production of melanin, which is why the eye color may darken or change over time. (parents.com)