Which came first: the hat or the bald spot?
It’s pretty common to see men and women who are suffering from hair loss wearing hats to cover their thinning hair, but there’s a pervasive idea that wearing hats might actually be the cause of baldness. Like many of these factoids that get whispered from person to person, there’s no real evidence to back them.
Alopecia, the technical term for hair loss, happens for a variety of reasons, from androgenic alopecia (aka male pattern baldness) to alopecia areata (hair loss in patches caused when the immune system affects hair follicles) (American Academy of Dermatology). But these are typically caused by genetics, medications, or underlying medical conditions, not hats.
Hats Definitely Don’t Cause the Most Common Type of Hair Loss
If hat wearing were the cause of balding, then we’d likely see many hat-lovers losing their hair. If you consider jobs that involve hats and helmets, people who wear hats frequently for sun protection, and those who sport hats as a regular piece in their wardrobes, that would add up to quite a few balding people.
But the most common type of hair loss, androgenic alopecia (sometimes called Male Pattern Baldness) isn’t caused by headwear. It’s caused by the male hormone dihydrotestosterone (DHT). It occurs when DHT bonds with the androgen receptors in hair follicles and causes the hair follicle to be miniaturized, resulting in a shorter growth cycle (The New England Journal of Medicine, 1999). This type of alopecia is generally the work of heredity, and hormonal changes or imbalances (such as Polycystic Ovary Syndrome in women).
The most common causes of other types of hair loss are thyroid conditions, malnutrition, psychological trauma, ringworm, medications and treatments, and possible autoimmune disorders (Clinical Key). In fact, there’s only one type of hair loss that’s really caused by hair styling: traction alopecia.
Is There Any Way that Hats Could Cause Any Kind of Hair Loss?
I can think of two ways that people might think that hats could be the cause of hair loss. One is the aforementioned traction alopecia, caused by putting pressure on the follicle. The other is a hat that somehow prevents nutrients from getting to the scalp by worsening circulation. Both of these are pretty unlikely.
Traction alopecia is typically caused by wearing hair in tight styles for prolonged time periods. This typically happens when someone regularly wears a style that puts strain on hair, such as cornrows, tight buns, braids, and sometimes even extensions. Overtime, this causes the follicles to weaken and the hairs they produce to become smaller until they fall out entirely (American Medical Association Archives of Dermatology, 1958).
Despite many sources saying blood flow and baldness are unrelated, I wasn’t able to find studies supporting this idea. In fact, I found several studies that found that blood flow might be involved in baldness. A study of 18 men, 9 with hair loss and 9 control participants, found that men with MPB had a significantly lower level of transcutaneous PO2 (blood oxygen levels) than men with a full head of hair (Plastic and Reconstructive Surgery, 1996). This caused tissue hypoxia, when a certain area of the body receives inadequate oxygen (British Medical Journal, 1998). Another study on 28 men, half bald, half not, found that bald men had a less nutritive blood flow to follicles (Journal of Investigative Dermatology, 1989).
But it’s unlikely that your hat will cause traction alopecia or low blood oxygen levels. In order to cause enough stress on hair or to limit nutritive blood levels and oxygen (i.e. worsen circulation) enough to cause balding, you would have to wear a very tight hat for a prolonged period of time. So, it would be very unlikely to experience hair loss as a result of wearing hats.
Is There a Hat that Might Actually HELP Hair Loss?
OK, it’s really more of a helmet (and sometimes a comb), but there’s a type of device that’s being explored as a treatment for hair loss. In 2007 the FDA approved a device to treat hair loss called the HairMax LaserComb that uses Low Level Laser Therapy (LLLT), or laser biostimulation. Since then, other companies have created their own devices using LLLT to treat hair loss. But the HairMax LaserComb was approved after the FDA reviewed its safety, not its efficacy. And while there are several industry-sponsored trials, there are few independent studies (Journal of Cutaneous and Aesthetic Surgery, 2010).
A 2009 double-blind, placebo (sham device)-controlled study affiliated with Lexington International, LLC, the company responsible for HairMax, researchers found that participants who used the real device saw a significant increase in hair regrowth and terminal hair density in men with androgenic alopecia (Clinical Drug Investigation, 2009).
In another randomized, double-blind, placebo (sham device)-controlled study, supported by medical device company Won Technology, researchers had participants test one of the helmet-type LLLT devices. They found that the group using the real device had greater hair density and hair diameter after 24 weeks of use (Dermatologic Surgery, 2013).
In one small, independent study I did find, researchers had seven participants (six female and one male) use the helmet type of LLLT device to treat hair loss and examined them at 3 and 6 months. At six-month mark: six of the seven participants had a decrease in vellus hairs (very fine, small hairs), and one had an increase; five out of seven participants had an increase in terminal hairs, and two had a decrease; three out of seven participants had an increase in hair shaft diameter, and four participants had a decrease. But, according to researchers, none of these differences were statistically significant. In subjective evaluations, reviewers saw improvement in only two cases, no change in four cases, and a decrease for one case (Journal of Cosmetic and Laser Therapy, 2009).
Overall, LLLT is a promising device, but given the cost and the fact that it might only help some people experiencing certain kinds of hair loss, it’s important to have larger, long-term, independent studies to gauge the effectiveness of this treatment.
To answer the question at the beginning of the article: Even if the hat came first, it didn’t cause the hair loss.
The most common type of hair loss, androgenic alopecia, is caused by several factors, including heredity and hormonal changes or imbalance, but not hats. If a hat were a contributing factor in traction alopecia, typically caused by wearing hair in tight styles frequently, it would have to be very tight. And if a hat contributed to the lower levels of oxygen and nutrient-rich blood, it would have to be tight enough to effect circulation. So, unless someone wears their hats so tightly that it puts stress on their hair or limits blood flow to the scalp, which seems pretty unlikely, their hats are the cause of their hair loss.
There is, however, a hat of sorts in the form of a LLLT helmet (though it’s also sometimes a type of comb) that might help those experiencing hair loss, but there aren’t enough independent studies to determine how well it works and who will benefit most.