A cikin Tsohon Rashanci, "ja" yana nufin "kyakkyawa". A cikin Polynesia, wannan ma’anar kalmar “masoyi” ce. A kasar Sin, ma'aurata suna yin ado da riguna masu irin wannan launi, kuma ana cewa "jajayen zuciya" game da mutum mai gaskiya. Romawa na dā sun ɗauki ja a matsayin alamar iko da iko. Masana ilimin halayyar dan adam sun tabbatar da cewa ja yana aiki kamar ba wani launi: yana da m, batsa, a cikin matsakaici yana dumi kuma yana farantawa, a cikin adadi mai yawa yana damuwa kuma yana haifar da tashin hankali. Don haka, kuna buƙatar amfani da ja sosai a hankali.
Idan sun rufe manyan jiragen sama, to, akwai haɗarin kashe duk sauran launuka na ciki. Amma idan kun yi amfani da shi a cikin sashi, a cikin nau'i na nau'i na launi daban-daban - a cikin drapery, matashin kai, shirye-shiryen furanni - zai faranta muku rai kuma ya ba ku haɓakar haɓaka. Sun ce jajayen mutane ne musamman masu karfi, masu mulki. A kowane hali, idan kuna so ba zato ba tsammani, mai yawa ja, to, muna ba da shawarar shi don ɗakuna inda rayuwa mai aiki ke cikin kullun: zauren, falo, ofis. Af, nutritionists da'awar cewa ja tada da ci, don haka idan kana so ka shirya ciki holidays, ajiye shi ga kitchen. Kuma, duk da yanayin salon, yana da kyau a zaɓi muted terracotta ko inuwa diluted.