Women lose more hair during the summer and autumn, according to a study using Google trends.

A 12-year study was conducted by researchers from John Hopkins University School of Medicine from January 2004 to October 2016 that examined trends in Google, whenever there is an increase in searches for the keyword ‘hair fall.’

Google trends enables users to search how a specific keyword was used over a specific period.

The researchers applied the search tool in eight countries in both hemispheres, all in English-speaking countries, using the keyword ‘hair fall.’

“The result of this secular trend study suggests that hair loss in the population is significantly correlated with seasonality,” wrote the researchers.

In summer and autumn, women generally experience hair fall, as more clumps of hair are caught in their hairbrushes.

“The 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,” said lead researcher Dr Shawn Kwatra, adding that hair loss is a frequently encountered dermatologic complaint that can result to psychological distress.

To help explain why this happens, the researchers offered that it is likely that the scalp holds on to hair follicles during summer months to protect the top of the head from harsh sunlight. When heat begins to subside at the end of summer and during fall, it will not need as much protection and thus results in hair fall.

The team intends to further their study on hair cycle, saying “future research will further clarify this association and examine the physiology of the hair cycle.”

However, limitations to the study include the shifting tendencies of data in Google trend, and that the study did not point to a biological connection on why hair falls on such specific seasons, compared with spring and winter.

The study was published in the British Journal of Dermatology. MIMS