A base tan refers to the slow, gradual tanning of the skin under either natural or artificial sunlight. In essence, it is a suntan achieved over time rather than from long period sun exposure over a short period of time. Many tanning salons suggest that tanning in this way can act as a protective measure against sunburn and recommend getting one in a tanning bed before going on beach vacations and tropical cruises.
The theory behind a base tan is that skin is gradually building up color and therefore becomes less likely to burn with sudden sun exposure, such as when vacationing on the beach or hitting the pool for the summer. This particular theory is widely debated, but professionals within the tanning salon industry take the stance that a building tan slowly and gradually is a far safer way to get darker skin than exposing the skin to extreme sunlight all at once.
The American Academy of Dermatology and most physicians argue that a base tan does not protect a person from sunburn. In reality, it may reduce the appearance of sunburn, but it is the UVA and UVB radiation exposure that damages the skin, regardless of whether the end result is red or brown skin. Additionally, many people mistakenly believe that having a tan means that they don't need protective sunscreen during full sun exposure and neglect their skin.
Whether or not a person elects to expose herself to the sun all at once or slowly over time, the important thing to remember is that there is no safe way to tan. While some UVA and UVB exposure is healthy, a sunscreen with an SPF of 15 should be used at all times to protect the skin from damaging ultraviolet light. UVA radiation is found in both artificial and natural sunlight and is a known cause of cancer.
While the risk factors and rates of melanoma development as a result of sun exposure are still being studied, most health professionals agree that a base tan is not a safe alternative to sunscreen and may give people a false sense of security.