Comparative Assessment of Red, Green and Black Pepper Species on Plasma and Fecal Lipid Profile of High-Fat Diet Fed Wistar Rats

The consumption of high-fat diets has been linked to various health conditions, including dyslipidaemia. The aim of the present study was to compare the impact of three pepper types on the plasma and fecal lipid profile [total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL) and low-density lipoprotein (LDL)] of high-fat diet fed wistar rats. The study involved forty-five wistar rats separated into nine groups of five rats each. Group 1 served as control while groups 2 to 9 were fed with high-fat diet throughout the period of the experiment. Group 2 received only high-fat diet. Groups 3 and 4 received in addition, 50mg/kg and 75mg/kg of red pepper respectively, Groups 5 and 6 received in addition, 50mg/kg and 75mg/kg of green pepper respectively, Groups 7 and 8 received in addition 50mg/kg and 75mg/kg of black pepper respectively. Group 9 received in addition 10mg/kg of simvastatin. The results showed that at a dose of 50mg/kg, both red and black pepper caused significant reduction in all the plasma lipid profile parameters while green pepper only caused reduction in TG and HDL. Comparatively, at 50mg/kg there was no significant difference in the lipid lowering effect of red and black pepper but rats fed with green pepper had significantly higher levels of LDL. At 75mg/kg, both green and black pepper caused significant reduction in all the lipid profile parameters. Comparing the effects of the three pepper types at 75mg/kg, green and black pepper caused a more significant lowering effect on plasma TC, TG and HDL than the red type. Conversely, fecal TC was higher in green and black compared to red pepper. There was no significant difference in the LDL levels of red and black pepper but LDL was higher in the red pepper group than the green pepper. At high doses, red pepper has a higher lowering effect on TC, TG and HDL while green pepper has higher lowering effect on LDL. No significant changes in faecal lipid profile parameters were observed upon administration of 50mg/kg of the pepper varieties but green and black pepper increased faecal loss of total cholesterol compared to red pepper. Conclusively, consumption of pepper together with high-fat diet would reduce the plasma concentrations of cholesterol. Green and black peppers are more potent plasma cholesterol lowering agents at high doses via increased fecal loss of cholesterol. However, the target cholesterol depends on the type of pepper. The findings suggest that the different pepper types exert varying degrees of influence on plasma lipid profile, with black pepper demonstrating the most consistent effects across doses. Therefore, pepper has therapeutic potential as a natural alternative or addition to current lipid-lowering drugs. Despite that high-fat diet is not often recommended, a high fat diet meal served with especially black pepper would be appropriate. Further research is necessary to completely understand the involved mechanisms and improve dosing regimens.