Background/aim: A novel complex of a nutritional supplement (CDB) contains chromium picolinate (CrPic), phosphatidylserine (PS), docosahexaenoic acid (DHA), and boron (B). The present study aimed to investigate the effects of CDB on the metabolic profile and memory acquisition in rats fed a high-fat diet (HFD). Materials and methods: Male Wistar rats were divided into six groups and received either a regular diet or HFD supplemented with or without different levels of CDB (0, 11, or 22 mg/kg BW). Results: Rats fed the HFD had greater glucose, insulin, lipid profile, and serum malondialdehyde concentrations, but lower serotonin and tryptophan in the serum and brain and lower Cr concentrations in serum, kidney, brain, and liver (P < 0.0001). CDB complex supplementation reversed all the effects, and the reversal effect was more pronounced with HFD for some parameters. Latency was less (P < 0.05) but probe was greater (P < 0.0001) for rats fed a regular diet. Increasing CDB complex levels in the diets resulted in a linear decrease in latency (P < 0.0002) but a linear increase in probe (P < 0.0002). Conclusion: Findings of the present work indicate that the CDB complex could be considered as an alternative treatment for preventing certain metabolic diseases and improving neurological functions, such as learning and memory.