However, it can cause allergic contact dermatitis. When taken orally, carotenoid dyes enter the bloodstream and are deposited in the skin. Although carotenoids are approved at low levels as food coloring, the amount needed to color the skin is much higher. Tanning pills have also been associated with anemia, allergy, abdominal cramps, liver damage, nausea, diarrhea, and eye discoloration. They are not approved by the FDA and should not be used.
Melanin is the skin pigment that gives the skin a tan color.
It is synthesized from the amino acid tyrosine, which is an ingredient added in tan accelerators. This assumes that tyrosine in tanning creams can penetrate the skin, diffuse through body tissues, enter melanocytes, and then increase production of melanin. Unfortunately, tyrosine, when applied through tanning creams does not work. More Self Tanning Tips Be sure that the product you use already has a sunscreen or use a separate one. Exfoliate your skin with a loofah before applying sunless tanning lotions to avoid uneven application of color.