Monthly Archives: October 2023

Skin Pigmentation, Skin Cancer and Vitamin D Deficiency

Skin Pigmentation, Skin Cancer and Vitamin D Deficiency

By Parnian Derahvasht, Grade 11, Ghods Girls High School, 8th District, Tehran, Iran

Humans have been migrating throughout history. It is believed that the first Homo sapiens migrated out of Africa about 50 to 70,000 years ago, likely due to climate changes in Africa. [1]

As they left Africa to settle in other regions of the planet, they also interacted with other archaic human species such as the Neanderthals and Denisovans who were already living in those areas. [2]

Factors such as UV exposure, altitude and latitude, food sources, the overall climate, etc. vary from location to location and each species that inhabits those areas must have the biological qualities that are required for its survival and reproduction in that environment. Our ancestors did not have those qualities when they first migrated out of Africa and it took many generations to gain those traits and for natural selection to take part in this process although interbreeding with the Neanderthals and Denisovans did speed up the process and was advantageous for our survival in the new environment.

Our adaptive introgression inherited from Neanderthals has affected genes associated with body fat distribution, muscle contraction, brain size and functioning, keratin filaments, enamel thickness, sugar metabolism, as well as oocyte meiosis. Humans inhabiting in various locations on Earth adapted to those places and, as a result, the genes related to variation in skin pigmentation and hair morphology showed signs of positive selection. [3]

Melanin, which provides the skin with pigmentation, is also a filter for the ultraviolet radiation (UVR) that we are constantly exposed to. Long-term exposure to the sun’s UVRs can damage our DNA and lead to the development of skin cancer. In order to resolve this issue, we evolved to have particular amounts of melanin according to the environment we live in.

For example, in places with high latitude and low UVR, it is more favorable to have lighter skin. This is because of the fact that there is not much UVR to damage the DNA, so having skin that allows these rays to penetrate the skin to produce vitamin D is crucial for the individual’s well-being in that environment. It is a similar situation for darker skin populations that live in low latitudes (near the equator) where there is high UVR. It is best to have highly pigmented skin for a protection against the sun’s high levels of UV radiations.

The Fitzpatrick scale is a numeric chart for human skin color classification. It was developed in 1975 by Thomas B. Fitzpatrick, an American dermatologist, as a way to guess the response of different types of skin pigmentation to UV light.[4] In the Fitzpatrick scale, there are six major skin color categories:

Type I: Always burns, never tans (palest; freckles)

Type II:  Usually burns, tans minimally (light colored but darker than fair)

Type III:  Sometimes mild burn, tans uniformly (golden honey or olive)

Type IV:  Burns minimally, always tans well (moderate brown)

Type V:  Very rarely burns, tans very easily (dark brown)

Type VI:  Never burns (deeply pigmented dark brown to darkest brown)

The potential of skin cancer varies between the categories, with the highest being in Type I, and the lowest chance being in Type VI. To put it simply: the lighter the skin the higher risk of developing skin cancer and burning. The darker the skin, the lower the risk of developing skin cancer and burning.

Although skin cancers can occur in any type of skin color, it is more likely to be seen in white populations as their skin is not well protected against the sun’s UV radiations. The most common type of skin cancer among white individuals is BCC (Basal Cell Carcinoma), followed by SCC (Squamous Cell Carcinoma). Both are non-melanoma skin cancers and can be cured if detected early. Lastly, the third most common kind of skin cancer is melanoma which can spread to other parts of the body and can be fatal.[5]

As said earlier, the human race has been migrating to new environments since our species first emerged. As human beings became more advanced, environmental factors became less of a reason for migration; instead, social and political factors such as wars, conflicts and government persecutions have been the main reasons for migration during these past centuries. Whatever the reason may be, not many people acknowledge the long-term health risks that come with migration to a completely different environment.

For years, there has been a skin cancer crisis in Australia. According to the website “World Cancer Research Fund International,” Australia had the highest overall rate of melanoma of skin in 2020, followed by New Zealand. [6] This could be because of a number of reasons including Australia experiencing high levels of UVR, resulting from the reduction in their ozone layer since the 1970s or the culture of tanning that has gained a lot of popularity over the decades. It is interesting to know that most of these cancer cases are in white Caucasian immigrants, and this is mainly because of the low levels of melanin that are produced in the skin, and thus having less protection against the sun’s UV rays than other races with darker skin tones.

On the other hand, some ethnic groups with darker skins, especially African Americans who live in North America are at greater risk of vitamin D deficiency.[7] Again, this could also be because of a number of reasons such as diet, health conditions that prevent the absorption of vitamin D and the overall increase in indoors time. A major amount of vitamin D that is produced by our body comes from the sun’s UVB rays, so it is obvious that skin types with high levels of melanin will have a hard time absorbing those UVB rays, thus producing insufficient amounts of vitamin D. The melanin in dark skin is twice as effective in blocking UVB compared to White skin. While the Black skin epidermis allows only 7.4% of UVB and 17.5% of UVA to penetrate the skin, 24% UVB and 55% UVA passes through white skin.[8]

If it has not become apparent by now, both of these cases (skin cancer and vitamin D deficiency) are more likely to be seen in immigrants from different countries and continents. Racial groups look different for a reason that has a lot to do with the race’s environment of origin; the relocation of those individuals might result in the health issues stated above.

As social and economic concerns are becoming more prominent every day, more people are choosing to emigrate to other countries; which means more people are going to be living in completely new environments that their biology has not adapted for.

To conclude, the best strategy for dealing with these issues is to take precautions. For light- skinned individuals living in tropical or subtropical areas, it is best to apply sunblock creams and avoid ‘tanning beds’ completely, because there is no such thing as “safe tanning.” People with darker skin living in polar and sub-polar zones should have a vitamin D rich diet along with other nutrients, and it might be better for them to be slightly more exposed to the sun than their light-skinned counterparts.

References:

[1] https://en.wikipedia.org/wiki/Early_human_migrations#:~:text=Around%201.8%20million%20years%20ago,around%201.9%20million%20years%20ago.

[2] https://en.wikipedia.org/wiki/Interbreeding_between_archaic_and_modern_humans#:~:text=Genes%20affecting%20keratin%20were%20found,cope%20with%20non-African%20environments

[3] Dolgova O, Lao O. Evolutionary and Medical Consequences of Archaic Introgression into Modern Human Genomes. Genes (Basel). 2018 Jul 18;9(7):358. doi: 10.3390/genes9070358. PMID: 30022013; PMCID: PMC6070777.

[4] https://en.wikipedia.org/wiki/Fitzpatrick_scale

[5] Bradford PT. Skin cancer in skin of color. Dermatol Nurs. 2009 Jul-Aug;21(4):170-7, 206; quiz 178. PMID: 19691228; PMCID: PMC2757062.

[6] https://www.wcrf.org/cancer-trends/skin-cancer-statistics/

[7] Harris SS. Vitamin D and African Americans. J Nutr. 2006 Apr;136(4):1126-9. doi: 10.1093/jn/136.4.1126. PMID: 16549493

[8] Brenner M, Hearing VJ. The protective role of melanin against UV damage in human skin. Photochem Photobiol. 2008 May-Jun;84(3):539-49. doi: 10.1111/j.1751-1097.2007.00226.x. PMID: 18435612; PMCID: PMC2671032.

I Have Two Names

I Have Two Names

By Joy (Peixin) Yin, grade 7, Mexico.

I have two names; a Chinese name and an American one. My Chinese name is Peixin (沛心) . It means “pure heart.” My American name is Joy. My parents named me that because they want me to be happy.

My Chinese name is the one that is official. It’s written all over my legal documents. On first days of school, when the teacher calls roll, I’m always last, because my last name is Yin (尹). But I always need to correct them, “I go by Joy, though.” Sometimes, the teacher forgets and keeps calling me Peixin. And sometimes, I hear laughs and giggles from my classmates. I feel guilty to say, that sometimes, I feel a bit ashamed for having a Chinese name. So, when someone asks me, “What’s your name?” I always tell them to call me Joy. When the substitute pauses while taking attendance, it’s always me. When I write my name on my computer or phone, it always gets autocorrected. It’s almost as if the universe hates my name.

My American name is what they call me. When my family moved to the U.S., my parents gave me my American name so it would be easier for people to remember me, and for it to not be awkward and embarrassing for me every time someone pronounced my Chinese name wrong. My American friends all know me as Joy. I feel connected to the name; I feel like it’s me. Yet, I always get reminded of my real name.

But after three years of living in my hometown in China again, my feelings towards my name have changed. In China, my classmates and teachers all called me Peixin (pronouncing it perfectly!), and I was normal for once. In school, I was able to improve my Mandarin as well (a hard process, but worth it!). During that time, I also felt more connected to my culture, and learned more about it, although I sort of missed my American name and identity.

By now, I’ve accepted the fact that both of my names are part of my identity. Different parts of it. And I’ve embraced my Chinese name more. Especially after I saw many Asians at my new international school use only their Asian names.

My two names are two parts of my identity—living together in harmony, forever and always.

Joy (Peixin) Yin, grade 7, Mexico. She adds: “Born in Wuhan, China, I have also lived in California for five years. I speak and write Mandarin Chinese and English but I am also trying my best to learn Mexican Spanish. I have never been a sports person. Instead, I’ve always loved reading and writing. I’m currently 13 years old, and attending an international school in Mexico City.”

Let it Have Meaning

Let it Have Meaning

Let it have meaning
When the thunder comes
Earth beating to the echoing drum of its beat
it will have meaning
the skies will alight
the rain will breathe life into the earth
and it will have meaning

When the fires light
Forests ravaged by the enraged flames
it will have meaning
the death will clear way for new growth
the ash will nourish the ground
and it will have meaning

When the darkness rears its head
Mind flooding with thoughts of escape
i can find no meaning
tears staining satin pillowcase
dread escaping, breathed in by those around me
there is no meaning

let sufferings occur
allow my soul and spirit to perish
my body crucified,
all i ask
let it have meaning

—Bansi Balar, age, 17, Texas. She adds: “While studying the poem ‘Dulce et Decorum Est,’ my history teacher said something that has stuck with me ever since. With what was likely little recognition of the profound impact his next few words would have, he noted that while prose may be the language of conveying meaning, poetry is the language of emotion. Typical speech is vital as the means through which humans communicate matters of rational significance; however, poetry is arguably even more vital as the means through which humans communicate grief, joy, rage, and all of the other things that cannot be truly understood through prose. My writing journey began with a creative writing class I took in my sophomore year, and was recently enriched by the Yale Young Writers Program I attended this summer. All in all, poetry is an outlet for me, and I have dedicated myself to it by writing in nearly any free time I get.”

Oh, What A Sweet Girl!

Oh, What A Sweet Girl!

By Addison Townsend, age 16, Utah.

Oh, what a sweet girl. What an innocent, kind, happy girl.

I didn’t know of anything but the perfect life. School was perfect, my family was perfect, and even something as small as my fish was perfect. My life was filled with the joy of ignorance, where there was nothing wrong in the whole wide world. And, oh how happy I was when I looked in the mirror and saw only a body and not the calories from the apple I ate an hour ago. And how tragic it was when that apple mutated to a dark obsession, soon to take over my whole life.

Thin was the first-word people would use to describe me, and it never offended me. But, as I continued to age, there was an expectation forming. What would they think of me when I gained weight? How would they react when I wasn’t a bottomless pit of food anymore? When I was big?

What would I think when I was big?

I think the word ‘comparison’ should be changed to ‘that which is impossible to overcome’. Pictures of my face reminded me of chipmunks hoarding nuts for the winter, while I envied the girls with round and youthful faces, enhanced by their chubby cheeks. Lunch became a study session and dinner became an afterthought. I wanted to lose weight and I didn’t have much time for meals anyway so how easy it was when I stopped eating. And how addicting it was to see an inch off of my stomach. When you have the body people would die for, how could I not fall in love with my illness? Hunger became a friend, one I could rely on every day, every hour, every minute. When everyone else left, a twisting stomach was still there.

When they ask, “Are you going to eat all of that?” the translator in my head vomits it out as, “Go stick a toothbrush down your throat.” Eventually, the portion sizes became as small as nothing, but I could still look in the mirror and see more than a skeleton.

Long sleeves and layered clothing became a daily necessity. I was playing a game with my body, how long can you go without food and how well can you hide it? I didn’t mind the layers though, my body clenched and shivered without any insulation. But that’s okay, shivering means you’re winning. Those bruises on your spine and your hair falling out in clumps mean you’re winning. Passing out means you’re winning.

But nothing about my illness felt like winning.

My anorexia’s whispers became a deafening scream as the caloric calculator in my head lit up like a scoreboard at a basketball game. My stomach begged for more than water, but nothing felt better than how the cool water slipped down my throat and hit my stomach. My head pounded at me to wake up, but you can’t be hungry when you’re asleep. My teeth clenched for anything but the gum I had fed it for the last week, but gum was just so low in calories and mental unrest. Hallucinations of a younger Addy begged, why do you do this to yourself? My once-perfect life had managed to flip itself into a food-focused, dizzying black hole. My mindset went from me praising my anorexia, to me running from it like a killer ready to murder what little of me there was left. My diseased mind furied, like an ex who desperately wanted to get back together.

You know, there are perks of going to the hospital. The people are nice for the most part and the beds are adjustable, but my once secret friend became less of a secret and less of a friend. Bite by bite, my mind screamed at me, shrieking the most heart-wrenching and life-ruining things at me. They say, “I would die for a body like that,” I urge, “I am dying.” They say, “No. You’re an inspiration.”

Some days it’s easier to die than to take one more bite.

But some days, you remember why you’re still breathing, swallowing. Some days, you remember the sound of your violin, the way the orchestra comes alive as you close your eyes and peace fills your whole body. Some days, you remember what it’s like to hug your dog and to have him wiggle his booty as you come in the door, so excited to see you’re still fighting. Some days, you remember the joy of being able to kiss your girlfriend and that feeling of never wanting to let her go. Some days, you remember what it’s like to be happy.

Years later, I’m still re-learning that ice doesn’t count as dinner and the reflection in a passing window is not a measure of my worth. And even now, after years of recovery, I still cannot un-memorize the calories of a peppermint.

So, Anorexia, I wrote you a letter:

Dearest Anorexia,

I’m breaking up with you. And no, I’m not going to say, “It’s not you, it’s me.” because it was you. You stole five years of my life that I’ll never be able to get back. I wish I could say I loved you, but what we had was not love. Love is supposed to be beautiful and filling and satisfying, but you hollowed me out, turned me into an empty shell of a human. You taught me dependency is love, not desperation, and I believed you. It took me five whole years to realize food wasn’t the enemy, but it was the voice in my spinning head promising control, perfection. You built a shrine of my bones and diet pill bottles, forcing me to worship you.

So, Anorexia, you can loom over me and scar me and nip at my heels, but today I build an empire out of every word you used to destroy me. I tear down your temples made of my self-hatred and face you, saying, “Do your worst.” You whisper I’ll never be perfect, I say I know. You say I’m disgusting, I say I’m beautiful. You scream I’ll never be happy, I cry back, I already am.

By Addison Townsend, age 16, high school Junior, Utah. She adds: ” I wrote this narrative about my experience with disordered eating as I would like to create more of a space to talk about the struggles of Anorexia. For five years, Anorexia broke me and coming out the other side of recovery, it is incredibly important to me that I prevent this from happening to anyone in the future. This is the true reason I value publication and strive for attention from others.”