In short, this claim may be loosely accurate based on the study, but has shaky reliability, and therefore should not be taken as completely true. The main study referred to in the Classic FM article was conducted by OnBuy, a UK based online marketplace (OnBuy). They claim that their study consisted of examining the 27 most popular music subreddits and counting the number of positive words used on each. While they provide numbers claiming to have reviewed hundreds of thousands of comments in total, there is no reputable research organization or references backing it. However, they do cite a psychotherapist named Şirin Atçeken. The company she works for, WeCure, is another UK based health company focused on cosmetic procedures such as plastic surgery and dental implants, but also provides trauma therapy (WeCure). In addition, their study has been referenced in other articles, such as in The Dubrovnik Times and iHeart Radio(The Dubrovnik Times)( iheart.com). The Classic FM article also mentions an article on Frontiers, a research publishing platform that provides evidence of music in general improving verbal memory (Frontiersin.org). However, neither jazz nor metal genres are referenced. Other articles also make claims that both jazz and metal has the happiest listeners, such as an article on musicessentials.com (themusicessentials.com). In conclusion, while there may be some evidence to suggest that jazz and metal are the happiest genres, it should be taken with a hefty grain of salt.
