Research has predominantly focused on the negative effects of adversity on health and well-being. However, the salutogenic perspective suggests that adversity may not always be detrimental (Antonovsky, 1996). In fact, under certain circumstances, adversity may have the potential for positive outcomes, such as increased resilience and thriving (Carver, 1998; Rutter, 1987). The “steeling effect” suggests that past experiences of adversity may increase resistance to later adversities. It proposes that moderate adversity may facilitate more adaptive functioning than no adversity or high levels of adversity (Rutter, 2006, 2012). The relationship between adversity and health may be optimally assessed using curvilinear models, yet the majority of previous studies have examined linear associations (Masten & Cicchetti, 2016). It is therefore the aim of this review to determine whether moderate adversity is associated with more adaptive functioning when compared to no and high levels of adversity. Practical implications and future research are also discussed.