Tehran University of Medical Sciences Journal of Biostatistics and Epidemiology 2383-4196 10 1 2024 09 28 19 32 Martin Lauran GKT School of Medical Education, King’s College London, London, UK Ali Jafari Farhikhtegan Hospital, Azad university of Medical Sciences, Tehran, Iran Kosar Ali College of Medicine, University of Sulaimani, Sulaimani, Iraq Seyed Hosseini TUMS 2024 08 05 2024 08 17 Background: This systematic review has been undertaken in order to assess the effects of hypocaloric, high-protein diets on weight loss and cardiovascular risk factors such as serum lipid levels in metabolically healthy obese adults. The primary outcomes measured include changes in pre- and post- diet mean BMI, LDL-C, HDL-C, TAG, and TC levels.  Method: Four databases including: Embase, MEDLINE (via PubMed), Cochrane and Web of Science were searched with no restrictions on language or publication period. Clinicaltrials.gov was also searched in order to identify unpublished or on-going studies. Results: Three of four studies included in this systematic review noted a significantly greater loss in pre- and post- diet mean BMI levels in the hypocaloric, high-protein diet group as compared to hypocaloric, non-high protein diets (control). Whilst pre- and post-diet mean LDL-C, HDL-C, TAG, and TC levels did not differ significantly among hypocaloric, high-protein and control diet groups. Conclusion: Hypocaloric, high-protein diets had an unclear effect on blood-lipid levels as compared to control. Weight loss however was significantly greater in the hypocaloric, high-protein group as compared to other hypocaloric, non-high-protein diet groups.  https://jbe.tums.ac.ir/index.php/jbe/article/view/1481