“…For example, depression has now been linked to water and air pollution (Lin et al, 2017; Liu, Chen, et al, 2020; Shao et al, 2021), mold and dampness (Shenassa et al, 2007), malnutrition (Aydoğan et al, 2019; Ghimire et al, 2018; Wei et al, 2018), low-quality housing (Kim, Jeong, et al, 2021), and living in cities (James et al, 2017), although the mechanisms behind some of these associations are still unknown. Nations with high levels of conflict—both with other nations and within the nation—may also have higher rates of depression because of the psychological toll of war and other forms of conflict on mental health (Farhood et al, 2013; Miller & Rasmussen, 2010; Thabet et al, 2004). Taken together, these studies predict that depression may have its highest prevalence in nations with high pollution, poor water quality, a high share of urban residents, high levels of malnutrition and physical illness, and high levels of conflict.…”