I don’t have a problem with people adding things to their coffee (my wife enjoys her coffee with cream and minimal disapproving head shakes from me) but I do think black coffee has its merits. It is my opinion that the vast majority of coffee additives are remnants from the first wave coffee notion that coffee is vile, caffeine is good and adding things to coffee makes it tolerable.
Drinking more coffee is linked to a lower risk of depression, according to a review of 26 studies published in Australian & New Zealand Journal of Psychiatry in 2016. For each cup of coffee consumed per day, the risk of depression decreased by 8 percent, the researchers found. However, it's worth noting that too much caffeine can cause problems in people who also suffer from anxiety, negating any beneficial effects the coffee can have on depression risk.