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Sunless tanning, also known as UV filled tanning, self tanning, spray tanning (when applied topically), or fake tanning, refers to the effect of a suntan without exposure to the Sun. Sunless tanning involves the use of oral agents (carotenids), or creams, lotions or sprays applied to the skin. [1] Skin-applied products may be skin-reactive agents or temporary bronzers (colorants).
The popularity of sunless tanning has risen since the 1960s after health authorities confirmed links between UV exposure (from sunlight or indoor tanning) and the incidence of skin cancer. [2]
The chemical compound dihydroxyacetone (DHA) is used in sunless tanning products in concentrations of 3%-5%. [3] DHA concentration is adjusted to provide darker and lighter shades of tan. The reaction of keratin protein present in skin and DHA is responsible for the production of pigmentation. [4]
A safe and effective method of sunless tanning is consumption of certain carotenoids [5] [6] [7] —antioxidants found in some fruits and vegetables such as carrots and tomatoes—which can result in changes to skin color when ingested chronically and/or in high amounts. Carotenoids are long-lasting. In addition, carotenoids have been linked to a more attractive skin tone (defined as a more golden skin color) than suntan. [8] Carotenes also fulfil the function of melanin in absorbing UV radiation and protecting the skin. [9] For example, they are concentrated in the macula of the eye to protect the retina from damage. They are used in plants both to protect chlorophyll from light damage and harvest light directly. [10]
Carotenaemia (xanthaemia) is the presence in blood of the yellow pigment carotene from excessive intake of carrots or other vegetables containing the pigment resulting in increased serum carotenoids. It can lead to subsequent yellow-orange discoloration (xanthoderma or carotenoderma) and their subsequent deposition in the outermost layer of skin. Carotenemia, or carotenoderma, is in itself harmless, and does not require treatment. In primary carotenoderma, when the use of high quantities of carotene is discontinued the skin color will return to normal. It may take up to several months, however, for this to happen. [11] [12]
Lycopene is a key intermediate in the biosynthesis of beta-carotene and xanthophylls.
Lycopene may be the most powerful carotenoid quencher of singlet oxygen. [13]
Due to its strong color and non-toxicity, lycopene is a useful food coloring (registered as E160d) and is approved for usage in the US, [14] Australia and New Zealand (registered as 160d) [15] and the EU. [16]
Sunless-tanning pills often contain β-carotene. The American Cancer Society states that "Although the US Food and Drug Administration (FDA) has approved some of these additives for coloring food, they are not approved for use in tanning agents." Also that "They may be harmful at the high levels that are used in tanning pills." [17]
Chronic, high doses of synthetic β-carotene supplements have been associated with increased rate of lung cancer among those who smoke. [18]
Canthaxanthin is most commonly used as a color additive in certain foods. Although the FDA has approved the use of canthaxanthin in food, it does not approve its use as a tanning agent and has issued warnings concerning its use. [19] When used as a color additive, only very small amounts of canthaxanthin are needed. As a tanning agent, however, much larger quantities are used. After canthaxanthin is consumed, it is deposited throughout the body, including in the layer of fat below the skin, which turns an orange-brown color. These types of tanning pills have been linked to various side effects, including hepatitis and canthaxanthin retinopathy, a condition in which yellow deposits form in the retina of the eye. [20] [21] Other side effects including damage to the digestive system and skin surface have also been noted. [22] [23]
DHA (dihydroxyacetone, also known as glycerone) is not a dye, stain or paint, but causes a chemical reaction with the amino acids in the dead layer on the skin surface. One of the pathways is a free radical-mediated Maillard reaction. [24] [25] The other pathway is the conventional Maillard reaction, a process well known to food chemists that causes the browning that occurs during food manufacturing and storage. It does not involve the underlying skin pigmentation nor does it require exposure to ultraviolet light to initiate the color change. However, for the 24 hours after self-tanner is applied, the skin is especially susceptible to ultraviolet, according to a 2007 study led by Katinka Jung of the Gematria Test Lab in Berlin. [26] Forty minutes after the researchers treated skin samples with high levels of DHA they found that more than 180 percent additional free radicals formed during sun exposure compared with untreated skin. Another self-tanner ingredient, erythrulose, produced a similar response at high levels. For a day after self-tanner application, excessive sun exposure should be avoided and sunscreen should be worn outdoors, they say; an antioxidant cream could also minimize free radical production. Although some self-tanners contain sunscreen, its effect will not last long after application, and a fake tan itself will not protect the skin from UV exposure. The study by Jung et al. further confirms earlier results demonstrating that dihydroxyacetone in combination with dimethylisosorbide enhances the process of (sun-based) tanning. This earlier study also found that dihydroxyacetone also has an effect on the amino acids and nucleic acids which is bad for the skin. [27]
The free radicals are due to the action of UV light on AGE (advanced glycation end-products) as a result of the reaction of DHA with the skin, and the intermediates, such as Amadori products (a type of AGE), that lead to them. AGEs are behind the damage to the skin that occurs with high blood sugar in diabetes where similar glycation occurs. [28] AGEs absorb and provide a little protection against some of the damaging factors of UV (up to SPF 3), [29] [30] However, they do not have melanin's extended electronic structure that dissipates the energy, so part of it goes towards starting free radical chain reactions instead, in which other AGEs participate readily. Overall tanner enhances free radical injury. [26] Although some self-tanners contain sunscreen, its effect will not last as long as the tan. The stated SPF is only applicable for a few hours after application. Despite darkening of the skin, an individual is still susceptible to UV rays, therefore an overall sun protection is still very necessary. [31] There may also be some inhibition of vitamin D production in DHA-treated skin. [32]
The color effect is temporary and fades gradually over 3 to 10 days. Some of these products also use erythrulose which works identically to DHA, but develops more slowly. Both DHA and erythrulose have been known to cause contact dermatitis.
Professional spray tan applications are available from spas, salons and gymnasiums by both hand-held sprayers and in the form of sunless or UV-Free spray booths. Spray tan applications are also available through online retail distribution channels and are widely available to purchase for in home use. [33] The enclosed booth, which resembles an enclosed shower stall, sprays the tanning solution over the entire body. The U.S. Food and Drug Administration (FDA) states when using DHA-containing products as an all-over spray or mist in a commercial spray "tanning" booth, it may be difficult to avoid exposure in a manner for which DHA is not approved, including the area of the eyes, lips, or mucous membrane, or even internally. DHA is not approved by the FDA for inhalation. [33]
An opinion [34] issued by the European Commission's Scientific Committee on Consumer Safety, concluding spray tanning with DHA did not pose risk, has been heavily criticized by specialists. [35] This is because the cosmetics industry in Europe chose the evidence to review, according to the commission itself. Thus, nearly every report the commission's eventual opinion referenced came from studies that were never published or peer-reviewed and, in the majority of cases, were performed by companies or industry groups linked to the manufacturing of DHA. The industry left out nearly all of the peer-reviewed studies published in publicly available scientific journals that identified DHA as a potential mutagen. A study by scientists from the Department of Dermatology, Bispebjerg Hospital, published in Mutation Research has concluded DHA 'induces DNA damage, cell-cycle block and apoptosis' in cultured cells. [36]
A novel class of compounds has been found to stimulate melanogenesis in a mechanism that is independent from α-melanocyte-stimulating hormone (α-MSH) activation of the melanocortin 1 receptor (MC1 receptor). This is accomplished via small molecule inhibition of salt-inducible kinases (SIK). Inhibition of SIK increases transcription of MITF which is known to increase melanin production. Work published in June 2017 has demonstrated compounds that have efficacy when applied topically to human skin. [37] These compounds are still however in pre-clinical stages of development. Future directions may include the incorporation of SIK-inhibitor compounds with traditional UV-blocking sunscreens to minimize UV-related DNA damage in the short term while providing longer term protection through endogenous melanin production.
Tanning accelerators—lotions or pills [38] that usually contain the amino acid tyrosine—claim that they stimulate and increase melanin formation, thereby accelerating the tanning process. These are used in conjunction with UV exposure. At this time, there is no scientific data available to support these claims.
The role of alpha-melanocyte-stimulating hormone (α-MSH) in promoting melanin diffusion has been known since the 1960s. [39] In the 1980s, scientists at University of Arizona began attempting to develop α-MSH and analogs as potential sunless tanning agents, and synthesized and tested several analogs, including afamelanotide, then called melanotan-I. [40]
In the European Union and United States, afamelanotide is indicated for the prevention of phototoxicity in adults with erythropoietic protoporphyria. [41] [42] [43] Afamelanotide is also being investigated as a method of photoprotection from in the treatment of polymorphous light eruption, actinic keratosis and squamous cell carcinoma (a form of skin cancer). [44] Bremelanotide is used for the treatment of generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. [45] [46]
To pursue the tanning agent, melanotan-I was licensed by Competitive Technologies, a technology transfer company operating on behalf of University of Arizona, to an Australian startup called Epitan, [47] [40] which changed its name to Clinuvel in 2006. [48]
A number of products are sold online and in gyms and beauty salons as "melanotan" or "melanotan-1" which discuss afamelanotide in their marketing. [49] [50] [51] The products are not legal in any jurisdiction and are dangerous. [52] [53] [54] [55] Starting in 2007 health agencies in various counties began issuing warnings against their use. [56] [57] [58] [59] [60] [61]
Eicosanoids, retinoids, oestrogens, melanocyte-stimulating hormone, endothelins, psoralens, hydantoin, forskolin, cholera toxin, isobutylmethylxanthine, diacylglycerol analogues, and UV irradiation all trigger melanogenesis and, in turn, pigmentation.
Bronzers [62] are a temporary sunless tanning or bronzing option. These come in powders, sprays, mousse, gels, lotions and moisturizers. Once applied, they create a tan that can easily be removed with soap and water. Like make-up, these products tint or stain a person's skin only until they are washed off.
They are often used for "one-day" only tans, or to complement a DHA-based sunless tan. Many formulations are available, and some have limited sweat or light water resistance. Walnut oil extract, jojoba extract, and caramel are ingredients frequently used in temporary bronzers. [63] If bronzer is applied under clothing, or where fabric and skin edges meet, most will create some light but visible rub-off. Dark clothing prevents the rub-off from being noticeable. While these products are much safer than tanning beds, the color produced can sometimes look orangey and splotchy if applied incorrectly.
A recent trend is that of lotions or moisturizers containing a gradual tanning agent. A slight increase in color is usually observable after the first use, but color will continue to darken the more frequently the product is used.
Just as with the term "sunless tanner", the term "bronzer" is likewise not defined by law, or by regulations enforced by the FDA. What is defined and regulated is the color additive DHA, or dihydroxyacetone. [64] (Note that the "color additive" dihydroxyacetone is itself colorless.) [65]
Air brush tanning is a spray on tan performed by a professional. An air brush tan can last five to ten days and will fade when the skin is washed. It is used for special occasions or to get a quick dark tan. At-home airbrush tanning kits and aerosol mists are also available.
Tanners usually contain a sunscreen. However, when avobenzone is irradiated with UVA light, it generates a triplet excited state in the keto form which can either cause the avobenzone to degrade or transfer energy to biological targets and cause deleterious effects. [66] It has been shown to degrade significantly in light, resulting in less protection over time. [67] [68] [69] The UV-A light in a day of sunlight in a temperate climate is sufficient to break down most of the compound. It's important to continue wearing SPF while self-tanning, as self-tanner is generally a fake and temporary tan, and your skin is still sensitive to the sun.[ citation needed ]
If avobenzone-containing sunscreen is applied on top of tanner, the photosensitizer effect magnifies the free-radical damage promoted by DHA, as DHA may make the skin especially susceptible to free-radical damage from sunlight, according to a 2007 study led by Katinka Jung of the Gematria Test Lab in Berlin. [26] Forty minutes after the researchers treated skin samples with 20% DHA they found that more than 180 percent additional free radicals formed during sun exposure compared with untreated skin.
A toxicologist and lung specialist at the University of Pennsylvania's Perelman School of Medicine (Dr. Rey Panettieri) has commented, "The reason I'm concerned is the deposition of the tanning agents into the lungs could really facilitate or aid systemic absorption -- that is, getting into the bloodstream. These compounds in some cells could actually promote the development of cancers or malignancies, and if that's the case then we need to be wary of them." [70] A study by scientists from the Department of Dermatology, Bispebjerg Hospital, published in Mutation Research has concluded DHA 'induces DNA damage, cell-cycle block and apoptosis' in cultured cells. [36]
Many self tanners use chemical fragrances which may cause skin allergies or may trigger asthma. Furthermore, some of them contain parabens. Parabens are preservatives that can affect the endocrine system. [71]
Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs, Cherenkov radiation, and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights.
Sunscreen, also known as sunblock, sun lotion or sun cream, is a photoprotective topical product for the skin that helps protect against sunburn and prevent skin cancer. Sunscreens come as lotions, sprays, gels, foams, sticks, powders and other topical products. Sunscreens are common supplements to clothing, particularly sunglasses, sunhats and special sun protective clothing, and other forms of photoprotection.
Sun tanning or tanning is the process whereby skin color is darkened or tanned. It is most often a result of exposure to ultraviolet (UV) radiation from sunlight or from artificial sources, such as a tanning lamp found in indoor tanning beds. People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing. Some people use chemical products that can produce a tanning effect without exposure to ultraviolet radiation, known as sunless tanning.
Indoor tanning involves using a device that emits ultraviolet radiation to produce a cosmetic tan. Typically found in tanning salons, gyms, spas, hotels, and sporting facilities, and less often in private residences, the most common device is a horizontal tanning bed, also known as a sunbed or solarium. Vertical devices are known as tanning booths or stand-up sunbeds.
Dihydroxyacetone, also known as glycerone, is a simple saccharide with formula C
3H
6O
3.
β-Carotene (beta-carotene) is an organic, strongly colored red-orange pigment abundant in fungi, plants, and fruits. It is a member of the carotenes, which are terpenoids (isoprenoids), synthesized biochemically from eight isoprene units and thus having 40 carbons.
Canthaxanthin is a keto-carotenoid pigment widely distributed in nature. Carotenoids belong to a larger class of phytochemicals known as terpenoids. The chemical formula of canthaxanthin is C40H52O2. It was first isolated in edible mushrooms. It has also been found in green algae, bacteria, crustaceans, and bioaccumulates in fish such as carp, golden grey mullet, seabream and trush wrasse.
D-Erythrulose (also known as erythrulose) is a tetrose carbohydrate with the chemical formula C4H8O4. It has one ketone group and so is part of the ketose family. It is used in some self-tanning cosmetics, in general, combined with dihydroxyacetone (DHA).
Carotenosis is a benign and reversible medical condition where an excess of dietary carotenoids results in orange discoloration of the outermost skin layer. The discoloration is most easily observed in light-skinned people and may be mistaken for jaundice. Carotenoids are lipid-soluble compounds that include alpha- and beta-carotene, beta-cryptoxanthin, lycopene, lutein, and zeaxanthin. The primary serum carotenoids are beta-carotene, lycopene, and lutein. Serum levels of carotenoids vary between region, ethnicity, and sex in the healthy population. All are absorbed by passive diffusion from the gastrointestinal tract and are then partially metabolized in the intestinal mucosa and liver to vitamin A. From there they are transported in the plasma into the peripheral tissues. Carotenoids are eliminated via sweat, sebum, urine, and gastrointestinal secretions. Carotenoids contribute to normal-appearing human skin color, and are a significant component of physiologic ultraviolet photoprotection.
Photoprotection is the biochemical process that helps organisms cope with molecular damage caused by sunlight. Plants and other oxygenic phototrophs have developed a suite of photoprotective mechanisms to prevent photoinhibition and oxidative stress caused by excess or fluctuating light conditions. Humans and other animals have also developed photoprotective mechanisms to avoid UV photodamage to the skin, prevent DNA damage, and minimize the downstream effects of oxidative stress.
Skin care or skincare is a range of practices that support skin integrity, enhance its appearance, and relieve skin conditions. They can include nutrition, avoidance of excessive sun exposure, and appropriate use of emollients. Practices that enhance appearance include the use of cosmetics, botulinum, exfoliation, fillers, laser resurfacing, microdermabrasion, peels, retinol therapy, and ultrasonic skin treatment. Skin care is a routine daily procedure in many settings, such as skin that is either too dry or too moist, and prevention of dermatitis and prevention of skin injuries.
Biological pigments, also known simply as pigments or biochromes, are substances produced by living organisms that have a color resulting from selective color absorption. Biological pigments include plant pigments and flower pigments. Many biological structures, such as skin, eyes, feathers, fur and hair contain pigments such as melanin in specialized cells called chromatophores. In some species, pigments accrue over very long periods during an individual's lifespan.
Indoor tanning lotions accelerate the tanning process, by promoting the production of melanin. Increasing blood flow to the skin is a proposed mechanism, which may in turn stimulate production of melanin by melanocytes. Historically, indoor tanning lotions have contained no sunscreen and offer no protection from the sun. However, many tanning lotions currently contain sunscreen. Unlike sunless tanning lotions, these are designed for use with an ultraviolet source such as a tanning bed or booth.
Tanning activators are chemicals that increase the effect of UV-radiation on the human skin.
Afamelanotide, sold under the brand name Scenesse, is a medication used to prevent phototoxicity and to reduce pain from light exposure for people with erythropoietic protoporphyria. It is a melanocortin 1 receptor (MC1 receptor) agonist and a synthetic peptide and analogue of α-melanocyte stimulating hormone. It is administered as subcutaneous implant.
Sunburn is a form of radiation burn that affects living tissue, such as skin, that results from an overexposure to ultraviolet (UV) radiation, usually from the Sun. Common symptoms in humans and other animals include red or reddish skin that is hot to the touch or painful, general fatigue, and mild dizziness. Other symptoms include blistering, peeling skin, swelling, itching, and nausea. Excessive UV radiation is the leading cause of (primarily) non-malignant skin tumors, which in extreme cases can be life-threatening. Sunburn is an inflammatory response in the tissue triggered by direct DNA damage by UV radiation. When the cells' DNA is overly damaged by UV radiation, type I cell-death is triggered and the tissue is replaced.
Photoaging or photoageing is a term used for the characteristic changes to skin induced by chronic UVA and UVB exposure. Tretinoin is the best studied retinoid in the treatment of photoaging.
Bain de Soleil was a brand of sunscreen that was produced by Bayer. It was affiliated with the Coppertone brand. The name Bain de Soleil is French for "sun bathing." The brand used the slogan "Welcome to a place more colorful." In the 1970s and 1980s, the brand used the slogan "Bain de Soleil, for the St. Tropez tan." The brand was discontinued in December 2019.
The Sunscreen Innovation Act is a 2014 law that amended the Federal Food, Drug, and Cosmetic Act to establish an expedited process for the review and approval of over-the-counter (OTC) sunscreens. The US Food and Drug Administration (FDA) had not approved a new active ingredient in sunscreen since 1999, despite some sunscreens having been approved and used overseas for a decade. The new law gave the FDA one year to respond to the existing backlog of sunscreen ingredient approval requests, and then 18 months to reply to any future applications.
Tanning may refer to: