Although he originally studied digestion, Wolf is known for his research into the
Roseto effect, which he became interested in while talking to a local doctor in 1961, and which he published a study about in 1963. In this study, he suggested the reason people living in
Roseto, Pennsylvania had fewer heart attacks was because of their close family relationships. He also published a study on the
placebo effect in
nausea in 1950 which has been called "seminal" and "one of the earliest reports on the power of placebo" by
Irving Kirsch. ==Death==