Ethnicity, Skin Aging, and Genetics
Stereotypes are everywhere, and skincare is no exception. You've heard the age-old adage, "Asians don't age"; "Black don't crack". How much of that is true? Does sun damage really matter or is it mostly genetics anyways? Why does Halle Barry look so young? We look into the recent Multi-Decade and Ethnicity study from Olay and P&G that’s buzzing on the internet, and delve into its findings, what it means, and its implications to the future of skincare.
A large scale Multi-Decade and Ethnicity Study is currently being conducted by Olay and P&G, with the help of 23&Me, a startup company that tests personal genomics, and has genotyped over a million people to date, using saliva samples. This benchmark study is taking large samples of women from various ethnic groups, in different age groups as volunteers. What’s impressive is the level of detail and the enormous scope of the study, from detailed questionnaires about lifestyle and subjective appearances to analysis of DNA, genomics, proteomics, hormone levels, and microbiomes using specialized tools to find out about the big questions about aging, genetics, and how you might slow down your aging process or even predict the more likely problems that you might face in the future. This study has been featured in Refinery29 and Essence.com as one of the most interesting studies that looks widely at skin aging over several decades, ethnicity, and its various relationships.
We dug a bit deeper into the study, following the lead researcher Dr. Rosemarie Osborne’s presentation at the 2016 Spring Dermatology Update where she presented the first part of the study’s findings in comparing Caucasian women to African American skin from various age groups. While the general summary of many available articles on the Internet about the MDE study are that some people are simply winners of a “genetic lottery”, the study has much more to say than that in our opinion.
Biologically/genetically, what are the things that begin to change?
- Gene expressions related to natural skin antioxidants begin to decline in the 20s.
- Gene expressions related to cell energy levels decline in the 30s.
- Expression levels of cell junction and formation of the stratum corneum (the uppermost layer of the skin) declines in the 50s, leading to poor barrier function
- Some people really are “lucky” and age significantly slower than others and may appear up to 10 years younger than their actual age. [See below Diagram 3 for the difference in actual vs appearance]
- The exceptional agers and regular people have the same genes, but in the exceptional agers, the beneficial genes are expressed better and for longer as they decline with age in others.
- DNA repair/replication, cell growth/cycle, cell survival, chromatin remodeling, response to oxidative stress, autophagy, protein degradation/ubiquitination, proteasome are expressed in roughly 2100 genes that everyone shares but in exceptional agers, they are expressed better into their later years.
Do people of different ethnicities age differently?
- Different ethnicities do in fact, age in different ways and are prone to different markers of aging. For example, wrinkling and skin elastosis is much more pronounced in Caucasians with lighter skin tones as they do not have the natural SPF factor of melanin that darker skinned people enjoy. Darker skinned patients on the other hand suffer more from pigmentation problems.
- When tested genetically, at least in this Boston based sample, many were found to be of mixed heritage, even if they self-identified as “black” or “caucasian.” People with mixed heritage may be susceptible to skin conditions or markers of aging typical of a different ethnicity than that to the ethnicity that they might self-identify with. In the study, the vast majority of the volunteers were found to be mixed, at least when looked at a genetic level. [See below Diagram 1 and Diagram 2]
- There seems to be more “exceptional agers” who seem to age about 10 years younger than their biological age, among African American women compared to the Caucasian descent women, in the people that were studied.
What about the effects of environment?
- Sun exposure is the most significant environmental stressor.
- African descent women in their 60s appear younger than their Caucasian counterpart in the same age group, although in the 20s age group both appear similar in age.
- The natural SPF factor that their darker skin affords does, in fact, delay sun-induced photo aging symptoms like wrinkling. The term “black don’t crack” isn’t without merit. African American women in their 60s have similar age profiles as Caucasian women in their 50s, suggesting that there is about a 10 year difference in how they age due to the effect of natural sun protection.
- Cellular senescence is strongly correlated to sun exposure in both Caucasians and African Americans however. Women who indicated that they love the sun or don’t pay much attention to sun protection showed signs of damage in both light skinned and dark skinned volunteers. Sun protection is important for everyone.
- Sun protection is an extremely important factor in the speed at which people show aging markers (like sun spots in Asians and wrinkling in Caucasians), and in both Caucasian and African American women, those who claimed to be conscious of the sun or stay away from the sun are consistently more younger appearing.
- Expression of these gene pathways can be affected in a positive way by treatment with nutrients, peptides, and certain natural extracts.
- Some compounds like Pal-KTTKS and olive oil derivatives have the capacity in-vitro to increase the theme expression of these energy related, aging related, and barrier related genes so that regular people might be able to benefit.
We asked Dr. Rosemarie Osborne, lead researcher of the MDE Study for a quick interview about her presentation at the Dermatology Update.
Diagram 1: Lots of shades of “white” - Click image to enlarge
Diagram 2: Shades of “black” - Click image to enlarge
Diagram 3: Age-Actual vs Appearance - Click image to enlarge