While there are many uncertainties regarding hair loss, researchers have determined that the condition may in fact have a peak season.

Tracking Concern For Hair Loss Around The World

A team led by Dr. Shawn Kwatra, assistant professor of dermatology at Johns Hopkins University, examined Google searches for the exact phrase “hair loss” from 2004 to 2016. The searches were conducted by residents of eight English-speaking countries around the world, such as the United States, Canada, Australia, South Africa, and the United Kingdom.

According to Live Science, hair loss searches spiked in the summer and fall for both hemispheres and reached a low in the middle of the spring.

It’s important to note that when the researchers say “summer,” they aren’t just referring to the US’s summer months. The searches peaked during the hottest months of the year for all of the countries in the study.

Not The First Team To Find This Pattern

The team is well-aware that someone searching for “hair loss” might not necessarily be losing his or her hair. But Dr. Kwatra told Live Science that the findings “back up the results of smaller studies involving patients the showed greater [hair loss] in the summer months.”

One such study from 2011 found that women lose the most hair in the fall months. That research involved 800 healthy women whose hair loss patterns were observed over the course of six years.

Previous studies have also reportedly shown that people have more “telogen” hairs in the summer than any other time of the year. “Telogen” hairs are those that are most likely to fall out because they are in the last of the three stages of hair growth.

Making Sense Of The Results

It’s unclear why temperature might be associated with hair loss but one popular theory revolves around the need for scalp hair to protect our heads from the summer sun. When temperatures begin to fall in the late summer and early fall, the need for scalp hair decreases.

The strength of outdoor ultraviolet rays, or the “UV index” may play a significant role as well.

"This finding is clinically relevant for patients presenting in the summer and fall months with worsened hair loss and has implications in assessing the effectiveness of therapies,” Dr. Kwatra said in a statement.

Last May, New York medical and cosmetic dermatologist Dr. Francesca Fusco told Daily Mail that an increasing likelihood of hair loss in the late summer and early fall can be attributed to evolution. This suggests that much like the animal kingdom, humans have always experienced more hair loss at this time, possibly for thousands of years.

Further research is needed to confirm the team’s findings but it’s safe to say that preventing this supposed seasonal trend in hair loss could prove to be just as difficult as stopping leaves from falling off trees when fall rolls around.