I heard that tanning happens in phases, what are they?
Tanning is the natural response of the skin to Ultraviolet light exposure. There are two types of tanning which occur. The first is known as Immediate Pigment Darkening which occurs during ultraviolet exposure and increases until exposure ends. It occurs in response to both UVA and certain visible wavelengths. No melanin production is involved. This response depends on various factors including previous exposure and skin pigmentation type. Darker skin will produce a more pronounced effect. The second type is called Delayed Tanning. Delayed tanning occurs 48 -72 hours after exposure and increases for 7 – 10 days. Duration depends on various factors including repeat exposure and may last for several weeks or months. This result is due in part to an increase in the size of melanin containing cells (melanocytes) in the skin and the increase in melanosomes within these cells. Many studies show that this may serve to protect the skin from UVA and UVB damage due to overexposure. Both of these