In the July 2000 edition of the Journal of Human Evolution, Nina Jablonski and George Chaplin, anthropologists from the California Academy of Sciences, pointed out that dark Eumelanin skin needs approximately five to six times more sunlight exposure than light skin to produce the same amount of vitamin D through photosynthesis.
People with darker skin tones have more melanin, a molecule that serves as a natural sunscreen. But this can also make it a little harder to get enough sun exposure.Historically, the absence of sunlight has often had a negative impact on human health. In the past, numerous children residing in densely populated and polluted industrial cities in northern Europe suffered from rickets. By the late 1800s, it was estimated that around 90% of children in industrialized Europe and North America showed signs of the disease, as indicated by autopsy studies referenced by Holick in the August 2006 Journal of Clinical Investigation and the October 2007 American Journal of Public Health.
Medical experts in Europe and North America began promoting complete sun exposure as a means to prevent rickets, thus marking the beginning of the era of tanning for health benefits. Recognizing the inadequacy of the weak winter sunlight in temperate areas, they recommended that children be regularly exposed to ultraviolet radiation from a mercury or carbon arc lamp for one hour, three times a week. This approach was proven to be effective in both preventing and treating the condition of rickets.
During this period, as the solar remedy for rickets gained popularity in medical circles, another significant disease, tuberculosis (TB), was also discovered to benefit from exposure to sunlight. Patients with TB, regardless of age, were advised to recuperate in sunny areas and typically returned in improved health. As knowledge about the sun's effectiveness in treating rickets and TB spread, attitudes towards sun exposure underwent a dramatic transformation in the Western world. A tan became highly prized as a new symbol of status, indicating both well-being and prosperity, as only the wealthy could afford seaside vacations and outdoor activities. Tanning was not only recognized as a medical therapy for TB but also for conditions like rheumatism, diabetes, gout, ulcers, and wounds. Sun-kissed skin became fashionable, while pale skin fell out of favor.
Multiple 2017 and 2018 studies showed a profound increase in vitamin D deficiency among the Black American and European populations! Getting enough vitamin D for black populations was a challenge as the modern workforce of developed nations spends much of its time inside; yet vitamin D is “an essential vitamin, meaning that we have to get it outside of ourselves,” because the body won’t produce enough of the vitamin if you aren’t getting sufficient sun exposure, according to Dr. LaTasha Seliby Perkins, a family physician at Georgetown University.
Medical Doctors emphasize vitamin D's crucial role in bone formation by aiding calcium and phosphorus. A deficiency in vitamin D increases the risk of osteoporosis. The U.S. National Institutes of Health, including various components like the Office of Dietary Supplements, organized an expert panel to address the vitamin D paradox among Black Americans. This paradox involves the lower rates of falls, fractures, and osteopenia among Black Americans despite often having low vitamin D levels compared to White Americans with similar deficiencies. Anthropologists suggest genetic differences between Neanderthal and Sub-Saharan Homo Sapien genetics as a possible explanation.
The science: "...initial step in the activation of cholecalciferol occurs in the liver, where vitamin D is transformed into 25-hydroxyvitamin D (referred to as 25(OH)D). This metabolite, 25(OH)D, is predominantly found in the bloodstream and serves as an established indicator of vitamin D levels. However, at physiological concentrations, this metabolite remains inactive. The subsequent step in vitamin D activation takes place in the kidneys and other organs/tissues, where 25(OH)D is converted into 1,25(OH)2D, the active metabolite. The production and breakdown of 1,25(OH)2D are tightly controlled processes. In cases where circulating levels of 25(OH)D are low, levels of 1,25(OH)2D are typically maintained at normal or slightly elevated levels." (AMA NIH, NLB Studies 2020-2023)
Many medications are available to manage high blood pressure. Individuals diagnosed with high blood pressure should also adopt a diet low in salt, sugar, and processed foods while increasing their magnesium intake as part of dietary modifications alongside prescribed medications. Early diagnosis and intervention can sometimes reverse the condition without causing harm to the kidneys and liver, as certain petropharmaceutical drugs may do.
Melanin is a universal natural dark polymeric pigment, arising in microorganisms, animals,humans and plants. Individuals with darker skin have higher levels of melanin, which affects the body's ability to produce vitamin D. The Office of Dietary Supplements (ODS) at the National Institutes of Health highlights the importance of vitamin D in bone health, calcium absorption, cell growth, blood sugar regulation, and supporting muscle, nerve, and immune system functions. Given the increasing evidence of climate change's negative impact on human and environmental health, it is essential to explore how climate change specifically influences the rates of skin cancer, heat-related fatalities, and infertility. Melanin has become a critical factor in adapting to climate warming. Skin cancer is the most prevalent cancer worldwide, with a notable increase in cases during the latter part of the 20th century, particularly affecting individuals with light skin.
When individuals with darker skin are exposed to increased sunlight, their melanocytes generate a greater amount of melanin. This melanin serves to absorb harmful ultraviolet (UV) rays, which are known to contribute to the development of skin cancer. The more pigmented your skin is or the higher the level of Eumelanin present, the greater protection you receive. Melanin not only shields the genetic material within your cells from UV radiation but also seeks out reactive oxygen species (ROS), which are produced during cell metabolism. Accumulation of ROS in cells can result in oxidative stress, premature aging, and various health issues such as diabetes and cancer. Melanin acts as a scavenger for ROS, enhancing antioxidants and eliminating free radicals in the process.
Melanin has attracted attention in various fields such as biomedicine, agriculture, and the computer sciences industry due to its diverse characteristics and excellent biocompatibility. Nonetheless, the specific macromolecular structure and polymerization mechanism of melanin are still not well understood because of the wide range of melanin sources, complex polymerization properties, and low solubility in certain solvents. This lack of clarity poses a significant obstacle to the advancement of melanin research and application. Moreover, there is ongoing controversy surrounding the synthesis and degradation pathways of melanin. Despite these challenges, new properties and applications of melanin continue to be uncovered.
In 2023, the U.S. Naval Research Laboratory embarked on a groundbreaking experiment that delved into the intricate world of space microbes, with a specific focus on unraveling the mysteries of novel melanin variations. The primary objective of this research initiative was to unearth unique forms of melanin that could potentially revolutionize the development of radiation-resistant protective coatings for spacecraft and space suits. By tapping into the protective prowess of melanin against cosmic radiation, scientists aimed to pave the way for enhanced safety measures in space exploration.
The significance of melanin in shielding against radiation exposure in space cannot be overstated. As the pigment responsible for the coloration of hair, skin, and eyes, melanin emerges as a formidable ally in safeguarding both humans and equipment from the harmful effects of cosmic radiation. This natural defense mechanism has positioned individuals with darker skin tones as potentially more physiologically suited for the rigors of space travel and extended missions in the cosmos.
Moreover, the year 2020 witnessed a pivotal moment in the realm of space research as researchers successfully synthesized alternative forms of melanin. These innovative variants held the promise of offering astronauts unparalleled protection from the perils of space radiation, thereby marking a significant stride towards ensuring the safety and well-being of spacefarers. By harnessing the capabilities of these synthetic melanin derivatives, the scientific community opened up a realm of possibilities for fortifying spacesuits and spacecraft against the harsh realities of the space environment.
In essence, the convergence of space microbiology and melanin research has ushered in a new era of exploration, where the quest for novel melanin variations stands as a beacon of hope for advancing the frontiers of space technology and human spaceflight. The tireless efforts of scientists and researchers in unraveling the secrets of melanin underscore the transformative potential of this pigment in shaping the future of space exploration and ensuring the resilience of astronauts in the face of cosmic challenges.
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