Three thousand years ago, Europeans had darker skin. What factors led to its lightening over time?

A new study has revealed that most Europeans had dark skin as recently as 3,000 years ago, according to the Jerusalem Post.

The research, led by Guido Barbujani from the University of Ferrara in Italy, examined the genomes of 348 individuals who lived between 1,700 and 45,000 years ago.

The pigmentation data was obtained from DNA extracted from ancient bones and teeth. Based on this information, scientists were able to determine the color of skin, eyes, and hair using genetic markers.

"Over the tens of thousands of years covered by the DNA samples, 63% of ancient Europeans had dark skin, while only 8% had light skin," says Barbujani.

The remaining individuals exhibited shades of skin color ranging between dark and light. Light-skinned people only became more common in Europe around 3,000 years ago. Even during the Copper and Iron Ages, approximately 5,000 to 3,000 years ago, half of the analyzed individuals still had dark or medium skin tones.

It was previously believed that modern humans arrived in Europe roughly 45,000 years ago and quickly developed lighter skin to adapt to lower levels of sunlight. Researchers clarified that lighter skin tones began to spread much later.

"Their skin color likely varied almost as greatly as that of modern humans," says anthropologist and paleobiologist Nina Jablonski from Pennsylvania State University.

She believes that an adequate amount of vitamin D was obtained from food in the past, which could explain why dark skin persisted longer than previously thought. According to her, the increase in light skin only around 3,000 years ago may be linked to changes in diet.

As the population grew and agriculture developed, the diet provided less vitamin D. This created a need to synthesize more vitamin D through the skin, and lighter skin was more effective for such tasks. The human body requires vitamin D for proper immune function, and dark skin allows less ultraviolet radiation to penetrate.

Advancements in DNA analysis have enabled the sequencing of DNA from individuals who lived thousands of years ago. Many DNA research methods developed in forensic science are now applied to the study of ancient remains. Using these methods, researchers concluded back in 2018 that a person living in Britain about 10,000 years ago had dark skin.

Scientists also suggest that some Neanderthals may have had light skin even before modern humans arrived in Europe, indicating that the evolution of skin pigmentation is more complex than previously believed.

As a reminder, scientists have discovered why our skin becomes more fragile with age. This new research may pave the way for treatments to slow skin aging in humans, helping to alleviate issues such as slow wound healing in later life.