Background/Objectives: The aim of this review was to examine: 1) the ability of CCK or analogues of CCK to influence satiation and changes in body weight generally; and 2) the efficacy of CCK in influencing satiation and eating behaviour specifically at physiological levels of dosing. Methods: A systematic review of the literature was performed following the PRISMA 2020 guidelines in five electronic databases (Cochrane, CINAHL, Scopus, Medline and Web of Science) investigating the effect of exogenous CCK or analogues on satiation and body weight. The search strategy was limited to peer-reviewed articles in human trials published in the English language since the journal inception until end July 2020. A meta-analysis of studies that infused CCK and measured satiation via changes in food/energy intake was also conducted. Results: A total of 1054 studies were found using the search terms which was reduced to 15 studies suitable for inclusion. Of the twelve studies measuring the effect on the weight of food ingested or energy intake, eleven showed a decrease. Of the ten studies which measured the effect on satiation via VAS scale, nine showed a significant effect. An analogue of CCK which can be administered orally failed to produce any weight loss at 24 weeks. The meta-analysis found the effect of CCK on satiation dosed at physiological levels was significant with a standardised mean difference of 0.57 (CI 95%: 0.30, 0.85, p < 0.0001). By comparison, CCK dosed at higher, pharmacological levels also had a significant effect with a standardised mean difference of 0.91 (CI 95%: 0.46, 1.36, p < 0.0001). Eight of the ten studies in the meta-analysis combined CCK infusion with some means to facilitate stomach distension. Conclusions: The present review found evidence that exposure to either the CCK-8 or CCK-33 variants of CCK results in an increase in satiation but no evidence for weight loss over the long term. At both physiological and pharmacological doses, CCK has a significant effect on satiation.