Beauty Tips For Body Care
Which oil is the best for your skin? Years ago I recommended grapeseed oil because of its high linoleic acid content, and I think I inadvertently may have contributed to the misconception that free fatty acids are the same as triglycerides (Which are the main content of oils).So, to make things even more confusing, the fatty acid composition of oils do contribute to the way that they feel on the skin and the effect that they have on the skin. As well, as the triglycerides are hydrolyzed by enzymes and bacteria they contribute free fatty acids to the skin. BUT, it's still disingenuous to make claims from an oil when the research was conducted on the free fatty acid. Everyone's rate of triglyceride hydrolysis will be different, the fatty acid composition of oils will vary from batch to batch, and no oil is made up completely of just one type of fatty acid.The common knowledge is to choose an oil high in linoleic acid and avoid ones high in oleic acid. Despite its popularity in skincare, olive oil is an oil which is high in oleic acid. Depending on the batch, between 55% to 83% of the fatty acids bound to the triglycerides in olive oil are oleic.There is research that has shown in many cases the application of olive oil can actually lead to an increase in trans-epidermal water loss, which is an analogue for the moisture barrier function of the skin. However, most of this research was performed on people with atopic dermatitis or newborns. It's important to make a logical leap and assume that the same will occur with healthy, normal skin. Additionally in many studies, they compared the effect of olive oil to sunflower seed oil, an oil where the triglycerides are mostly made up of linoleic acid. They usually find that trans-epidermal water loss drops with the use of sunflower oil.Very often these studies are small, in one study that did show a negative effect of olive oil and a positive effect for sunflower oil - there were only 7 participants in each group. Larger studies, like one with 115 newborns found no significant difference in the effect of olive and sunflower oil, they were both moisturizing and reduced trans-epidermal water loss. One study I found on newborns even found a worsening of skin condition with the use of sunflower oil.So there's a lot of problems with this body of research, a study group that doesn't necessarily reflect a "normal" population (newborns and people with atopic dermatitis), and often very small and underpowered sample sizes.It's hard for me to make a recommendation for a "best" oil, as there are almost just as many studies to show a negative effect from olive oil as there are to show that it has a beneficial effect. All the researchers emphasize that further research is needed, and unfortunately, I think the answer is yet to be decided.Also keep in mind that oils are largely made of triglycerides, but there are other components too! Olive oil, for example, contains squalene and phenolic compounds with anti-oxidant effects like oleuropein.So if you are using a skin oil, you may benefit from switching to an oil with higher linoleic acid content (especially if you're a newborn or a person with atopic dermatitis) - but I don't think there's enough evidence to sanctimoniously berate someone who uses olive oil on their skin.Also, if someone markets their oil as being "similar to human sebum", run! Even with jojoba oil, while the wax esters are similar - it's not the entire composition and the claims fall apart under any real scrutiny.Impact of topical oils on the skin barrier: possible implications for neonatal health in developing countries DOI: http://doi.org/10.1111/j.1651-2227.2002.tb03275.xOlive oil, sunflower oil or no oil for baby dry skin or massage: A pilot, assessor-blinded, randomized controlled trial DOI: http://doi.org/10.2340/00015555-2279The permeability barrier in essential fatty acid deficiency: Evidence for a direct role for linoleic acid in barrier function DOI: http://doi.org/10.1111/1523-1747.ep12541775Evolution of lipid composition in skin treated with blackcurrant seed oil DOI: http://doi.org/10.1111/j.1467-2494.1988.tb00014.xInfluence of sunflower seed oil on the skin barrier function of preterm infants: A randomized controlled trial DOI: http://doi.org/10.1159/000363380
Girls Blog 2015
Submitted by kindofstephen
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