World Redhead Day 2023: 3 fast facts about redheads

World Redhead Day celebrates people who have naturally red hair every year on May 26.

There are a lot of interesting facts about people who have red hair. So in honor of World Redhead Day, VERIFY is fact-checking three fast facts about redheads.

Do redheads naturally produce more vitamin D?

Yes, redheads naturally produce more vitamin D.

The same genetic trait that causes red hair also makes redheads more sensitive to ultraviolet (UV) light, according to UCI Health. But that sensitivity also allows redheads’ bodies to produce more vitamin D, which is essential to bone development and good health.

A person’s body generates vitamin D when the sun’s ultraviolet B (UVB) rays penetrate the top layer of the skin, Health says. The UVB rays interact with a protein in a person’s skin (7-dehydrocholesterol, or 7-DHC) and activate a process to convert the protein into vitamin D3.

In 2020, researchers at Charles University and the Institute of Endocrinology in Prague, Czech Republic, found that redheads are more efficient at synthesizing vitamin D.

Is there an annual redhead festival? 

Yes, there is an annual redhead festival in the Netherlands.

Tens of thousands of redheads from over 80 countries gather in the Netherlands every summer for the annual Redhead Days international festival. It is said to be the oldest and largest redhead festival in the world.

Everyone, including non-redheads, is welcome to attend the free, weekend-long festival. The only activity that is exclusively for natural redheads is the big group photoshoot, which happens on the last day of the event.

This year’s Redhead Days festival will take place in Spoorpark, Tilburg, the Netherlands, from Friday, Aug.25 to Sunday, Aug. 27, 2023. 

Are redheads with blue eyes rare?

Yes, redheads with blue eyes are rare.

When you meet a redhead with blue eyes, you are looking at the rarest color combination of all human beings, according to the University of Melbourne, a public research university located in Melbourne, Australia, and Healthline.

About 17% of the world’s population has blue eyes, and an estimated 1-2% of people worldwide are said to have red hair. This means that the odds of having both red hair and blue eyes are around 0.17%, Mark Elgar, Ph.D., an evolutionary biology professor at the University of Melbourne, said in 2018.

Healthline says that gene characteristics fall into two categories: recessive and dominant — and a person’s parents share the blueprint of many of their features, from hair color to personality, in their genes.

Hair color is influenced by multiple genes, and dominant genes generally win out against recessive genes. That’s why brown hair and brown eyes, which are both dominant, make up such a large percentage of hair-eye color combinations.

But the red hair and blue eye combination is so unusual because it is the result of two different sets of DNA instructions, or mutations, happening in the same person, according to Elgar.

“The mutations occurred tens of thousands of years ago, and have now become established as different versions or variants of the genes that help determine our skin and eye color,” Elgar said.

“Red hair and blue eyes are both recessive traits which means a person needs to inherit both of the genes for red hair and blue eyes, from both parents. In contrast, brown hair and brown eyes are dominant traits, which is why they are much more prevalent,” Elgar continued.