CLOSE
iStock
iStock

Why Does Hair on Moles Grow More Quickly?

iStock
iStock

In medieval Europe and early colonial America, moles were seen as a sign of demonic possession (as was everything else). The ancient Greeks and Chinese, however, used the markings to try to decipher personality traits or destinies. In the age of modern pop culture, icons like Marilyn Monroe, Goldie Hawn, Cindy Crawford, and Madonna have turned moles into beauty marks to be desired and even emulated. But as anyone whose skin is accentuated by a mole can tell you, there is something particularly unique about them: They seem to grow hair at a faster rate than ordinary skin, and that hair often seems darker and coarser.

Why is this? Why do hairs burst forth from moles more quickly than they do from ordinary skin? Science actually doesn’t know.

“The short answer is that we’re not sure why the hair is coarser in moles or why it may seem to grow faster,” Lauren Ploch, a dermatologist based in Augusta, Georgia, tells mental_floss. “The development of moles is still a dermatologic mystery, as is the regulation of hair growth.”

When viewed under a microscope, nevus cells, a kind of melanocyte found in moles, don't invade the structure of hair follicles and seem to have no effect that would change hair appearance or growth, says Ploch.

Researchers do know that mole skin is different from other skin and develops as the result of a number of factors, including genetics, environment, hormones, and signaling proteins. Many of these elements (especially hormones and signaling proteins) also contribute to hair growth, says Ploch. So the presence of the mole and the underlining causes of it may tinker with the usual bodily factors regulating hair growth.

“I suspect that, while the mole itself may not have a direct role in creating a darker, coarser hair, the local milieu of signaling molecules and hormones in the skin that created the mole leads to a darker, coarser hair within the lesion,” she says.

She adds that moles often develop during puberty in response to androgen, the same steroid hormone that spurs facial and pubic hair growth, so moles and hair have a common stimulus. 

Science has yet to fully explain the behavior of moles, but at least we know more about them than we did during the middle ages.

nextArticle.image_alt|e
iStock
arrow
Big Questions
Why Does Turkey Make You Tired?
iStock
iStock

Why do people have such a hard time staying awake after Thanksgiving dinner? Most people blame tryptophan, but that's not really the main culprit. And what is tryptophan, anyway?

Tryptophan is an amino acid that the body uses in the processes of making vitamin B3 and serotonin, a neurotransmitter that helps regulate sleep. It can't be produced by our bodies, so we need to get it through our diet. From which foods, exactly? Turkey, of course, but also other meats, chocolate, bananas, mangoes, dairy products, eggs, chickpeas, peanuts, and a slew of other foods. Some of these foods, like cheddar cheese, have more tryptophan per gram than turkey. Tryptophan doesn't have much of an impact unless it's taken on an empty stomach and in an amount larger than what we're getting from our drumstick. So why does turkey get the rap as a one-way ticket to a nap?

The urge to snooze is more the fault of the average Thanksgiving meal and all the food and booze that go with it. Here are a few things that play into the nap factor:

Fats: That turkey skin is delicious, but fats take a lot of energy to digest, so the body redirects blood to the digestive system. Reduced blood flow in the rest of the body means reduced energy.

Alcohol: What Homer Simpson called the cause of—and solution to—all of life's problems is also a central nervous system depressant.

Overeating: Same deal as fats. It takes a lot of energy to digest a big feast (the average Thanksgiving meal contains 3000 calories and 229 grams of fat), so blood is sent to the digestive process system, leaving the brain a little tired.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

nextArticle.image_alt|e
Getty Images
arrow
Big Questions
How Are Balloons Chosen for the Macy's Thanksgiving Day Parade?
Getty Images
Getty Images

The balloons for this year's Macy’s Thanksgiving Day Parade range from the classics like Charlie Brown to more modern characters who have debuted in the past few years, including The Elf On The Shelf. New to the parade this year are Olaf from Disney's Frozen and Chase from Paw Patrol. But how does the retail giant choose which characters will appear in the lineup?

Balloon characters are chosen in different ways. For example, in 2011, Macy’s requested B. Boy after parade organizers saw the Tim Burton retrospective at the Museum of Modern Art. (The company had been adding a series of art balloons to the parade lineup since 2005, which it called the Blue Sky Gallery.) When it comes to commercial balloons, though, it appears to be all about the Benjamins.

First-time balloons cost at least $190,000—this covers admission into the parade and the cost of balloon construction. After the initial year, companies can expect to pay Macy’s about $90,000 to get a character into the parade lineup. If you consider that the balloons are out for only an hour or so, that’s about $1500 a minute.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios