Beauty Tips For Body Care
Avobenzone is a great organic (“chemical”) UVA sunscreen filter used world wide. Avobenzone is recognized as safe and unharmful to the skin as long as it is stabilized— good thing is many stabilizers exist. Unfortunately some of these stabilizers trigger allergic reactions in some people.Studies Exploring antioxidant potential to stabilize avobenzoneStudy: Photodegradation of avobenzone: stabilization effect of antioxidants.TL;DRAvobenzone is one of the most common UVA-filters in sunscreens, and is known to be photounstable...The tested antioxidants were vitamin C, vitamin E, and ubiquinone. ...Vitamin E (1:2), vitamin C (1:0.5) and ubiquinone (1:0.5) were the more effective concentrations increasing the photostability of avobenzone. In sunscreen formulations, the most effective photostabilizer was ubiquinone which also promoted an increase in SPFConclusion- Tocopherol (Vitamin e), Coenzyme Q10 (Ubiquinone) and Vitamin c all succeeded in having some stabilizing effects on avobenzone and are worth looking for in sunscreen. Q10 also enhanced its protectivenessRelated A study on how incorporation of tocopherol compounds (vitamin e) into sunscreen products aids in reducing dna damage from uv exposureRelated Related Study Human skin is damaged not just UVA1, UVA2, UVB light (which sunscreen protects from) but also by infared lightA study on how a complex of antioxidants can help protect skin from IRA light~~~~~~~~~~~~~~~~~~~~~~~~~~Exposure to Sunlight is known to cause reactive oxygen species that damage the skin. Since no sunscreen absorbs or reflects 100% of uv light, researches ran a study to explore the possibility of whether adding two weak antioxidant derivatives could deactivate some ROS.Study:Bioconvertible vitamin antioxidants improve sunscreen photoprotection against UV-induced reactive oxygen species.TL;DR...Two-photon fluorescence imaging microscopy was used to determine the effect of sunscreen/antioxidant combinations upon UV-induced ROS generation in ex vivo human skin. A sunscreen combination containing octinoxate & avobenzone ...spf 8 and spf 15...was tested...A UV dose equivalent to two hours of North American solar UV was used to irradiate the skin...Each sunscreen reduced the amount of ROS induced in the viable strata by a value consistent with the SPF level. UV photons that were not absorbed/scattered by the sunscreen formulations generated ROS within the viable epidermal layers...The addition of the bioconvertible antioxidants vitamin E acetate and sodium ascorbyl phosphate...improves photoprotection by converting to vitamins E and C, respectively, within the skin...*The bioconversion forms an antioxidant reservoir that deactivates the ROS *generated (within the strata granulosum, spinosum, and basale)Conclusion - adding SAP and Tocopherol acetate to sunscreen did show promise for deactivating reactive oxygen species in the dermis and lower epidermis (but not the top layer of skin)~~~~~~~~~~~~~~~~~~~~~~~~~~Oxybenzone, Octinoxate and Avobenzone are popular sunscreen filters in the USAThis study tests the antioxidant potential of grapeseed extract in providing extra stabilization to these sunscreen filters so they do not degrade in light as quicklyStudy: Photodegradation of avobenzone: stabilization effect of antioxidants.TL;DRThe photostabilizing ability of grape seed extract ...was investigated. Samples were exposed to simulated solar radiation and monitored by spectrophotometric and chromatographic methods. ...UV radiation increased the UV absorption capacity of the extract. All sunscreens showed an improved photostability in the extract. The inherent photo-instability of (avobenzone) when exposed to UV radiation was almost eliminated in the presence of grape seed extract. ...all three sunscreens in the extract showed very high photostability and a red shift covering the entire UVB and UVA regions, thereby improving the broad-spectrum protection.Conclusion - The incorporation of grape seed extract in sunscreen and other cosmetic formulations for topical application boosts photoprotection by stabilizing the UV filtersRelated An in vivo study showing that when grapeseed extract is applied to the skin (sans sunscreen) there was less sun burn cells and cell damageRelated Related study More on vitis vinifera seed extract/grapeseed extract~~~~~~~~~~~~~~~~~~~~~~~~~~Some consumers worry about effects of skin permeation of certain sunscreen filters, even ones that may not necessarily accumulate in the body. One of main concern is octinoxate for pregnant women.Study: Trans-resveratrol and beta-carotene from sunscreens penetrate viable skin layers and reduce cutaneous penetration of UV-filters. Note Study was done on pig skin which is similar to human skin - much more so than a lab ratTL;DRFormulations containing octocrylene, (octinoxate), avobenzone and (Tinosorb s) were prepared and supplemented or not with BTC, or with RES, or with both compounds in combination....Results suggested that UV-filters and antioxidants did not permeate the skin but were retained for 12h post application. About 90% and 80%, respectively, of the total penetrated amount of UV-filters and antioxidants was found in the (stratnum corneum)...observations That BTC, alone or combined with RES, reduced the skin retention of UV-filters on average by 63%.Conclusion - About 90% of the sunscreen filters did not even pass the first layer of human epidermis. This study demonstrated that the combination of antioxidants and UV-filters in sunscreens may be advantageous for penetration, BTC improved sunscreen safety by reducing delivery of the four UV-filters in the study into SC and viable epidermis.
Girls Blog 2015
Submitted by Darker-Day
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