The consumption of energy dense snacks and some contextual factors of snacking may contribute to higher energy intake and body weight in adults.

Preventing obesity (OB) among adults is a public health priority. One factor that seems to contribute to OB, due to the extra energy intake it involves, is the greater consumption of snacks. Whether snacking promotes OB in adults is however a source of controversy in the literature at present. The aim of this paper was to evaluate the effects of snacking on body weight status, along with contextual factors such as snacking location, food source, timing, and social context of snacking. To better understand the nature of snacking behavior, seven currently used definitions of snacking were described. Studies published prior to November 2020 were identified by searching the PubMed and Scopus databases, with thirty-three observational studies being identified and included. The consumption of energy-dense snacks may contribute to higher energy intake and weight in adult populations. The context in which adults snacks-such as eating alone, outside home or work, late in the day, in front of a TV or computer-is also important for this behavior. However, the lack of consensus on the definition of snacks in the literature makes these considerations suggestive rather than objective. Better-designed research is needed to determine the prospective association between snacking behavior and weight status in adults. Snacking may be an important behavior that can be modified to prevent obesity on the population level. Social education focused on promoting morning snacks and replacing energy-dense snacks by more nutritious ones, e.g. fruit and vegetables, may thus be beneficial.