What is Erythrulose?

D-erythrulose (also known as erythrulose) is a four-saccharide carbohydrate with the chemical formula C4H8O4.It has a keto group and thus belongs to the ketose family.It is often used in some self-tanning cosmetics in combination with dihydroxyacetone (DHA).Erythrulose/DHA reacts with amino acids in the proteins of the first layer of skin (stratum corneum and epidermis).One of these pathways involves free radicals, one of the steps in the Maillard reaction,closely related to the browning effect of cut apple slices when exposed to oxygen.Another pathway is the traditional Maillard reaction; both pathways are involved in browning during food preparation and storage.This is not a stain or dye, but a chemical reaction that produces a color change on all treated skin.It does not involve underlying skin pigmentation, nor does it require exposure to UV light to trigger a color change.However, the "tan" produced by erythrulose/DHA had an SPF of only 3,and enhanced UV-induced free radical damage within 24 hours of self-tanning (compared to untreated treated skin), according to a 2007 study led by Katinka Jung of the Gematria Testing Laboratory in Berlin.After the researchers treated skin samples with high concentrations of erythrulose for 40 minutes, they found that 140% more free radicals were formed during sun exposure compared to untreated skin.

DHA produces similar results, but more quickly; however, erythrose takes longer to exert its full effect and therefore lasts longer.They said .The day after tanning, excessive sun exposure should be avoided and sunscreen should be applied outdoors; antioxidant creams also minimize the production of free radicals.While some self-tanning products contain sunscreen, the effects won't last as long as tanning products.During UV exposure, free radicals are generated, mainly superoxide/hydrogen peroxide (O2•−/HO2•) and other reactive species (ROS/RNS), which can react with ketoamines (Amadori products) and Maillard other intermediates react.This leads to an autoxidative free radical chain reaction of ketoamines, leading to a dramatic increase in free radical damage to the skin. This can be inhibited by antioxidants, suggesting the involvement of reactive oxygen species (ROS).Ketoamines have been shown to cause DNA strand breaks and act as mutagens. 

Free radicals are caused by the action of ultraviolet light on AGEs (advanced glycation end products) due to DHA reacting with the skin, and causing them.AGEs absorb UV light but don't have the extended electronic structure of melanin to dissipate the energy, so part of it is used to start a free radical chain reaction that other AGEs can easily participate in.AGEs are responsible for skin damage caused by hyperglycemia in diabetics, where similar glycation occurs.Erythrulose is a clear to pale yellow liquid found naturally in red raspberries.According to one method, it is produced by aerobic fermentation of Gluconobacter, followed by extensive multi-step purification.

Erythrose and dihydroxyacetone (DHA) are very similar in composition and react in much the same way on the surface of the skin. Erythrulose produces a lighter, slower-growing tan that takes 24 to 48 hours to develop.When used alone, it fades faster than DHA-based sunless tanners. Some people feel that the final shade of erythrose is slightly redder and less bronzed than a DHA-based tan. It may reduce dryness on the skin's surface, helping to provide a smoother faded tone. When combined with DHA, [Who Said? ] Tanned skin lasts longer,fades better,and provides a more aesthetically pleasing [citation needed] tone.It is found in 1% to 3% of sunless tanning products.

Because the skin is constantly shedding itself, losing thousands of dead skin cells each day, the tan is temporary.The tan look lasts from 2 to 10 days, depending on application type and skin condition.Not all users will develop a tan from erythrulose.Some people may find their fade more uneven and patchy when using this ingredient.Due to the added cost associated with this ingredient, some manufacturers consider it an ineffective addition to sunless tanning lines.Individuals sensitive to DHA may be able to use erythrulose as a skin-safe self-tanning alternative.Erythrulose is more expensive and difficult[citation needed] to obtain.Erythrulose is not currently approved by the Food and Drug Administration (FDA) for use as a self-tanner.