Effects of resistant starch-enriched low-fat vegetable butter on blood lipids, liver enzymes, and immunity in adults: a triple-blind randomized trial

Margarines have undergone many changes in composition and processing since their invention, resulting in many different products. For a long time, fats obtained from the partial hydrogenation of vegetable oils were used to obtain solid fats at room temperature. Currently, esterified fat is used as the main fat source for producing margarine. However, there are still attempts to make some changes to make the product healthier. This study aims to investigate the effect of consuming low-fat vegetable butter enriched with Resistant Starch on the levels of blood lipid factors, liver enzymes, and antibodies. This trial included 70 adult people who were randomly assigned to the normal and prebiotic butter groups in a parallel design. The profile of FBS, total cholesterol, LDL, HDL, and triglycerides, A1C, as well as liver enzymes including SGOT, SGPT, ALKP, CBC profile, total antibody IgA, IgM, and IgG, were measured before and after a 6-week daily intake of 50 g butter. According to the per-protocol analysis, the level of FBS reduced significantly in both groups (from 77.50 to 71.00 (P = 0.008), in the prebiotic and from 76.00 to 70.00 in the normal butter group (P = 0.001)). While consuming normal butter increased the total cholesterol from 150.17 to 178.43 (0.001), prebiotic butter decreased the total cholesterol from 175.38 to 153.40 (P = 0.004). The HDL level increased in both groups. The level of liver factor enzymes did not show a significant change, except Alkaline Phosphatase (ALKP), which was decreased in the normal butter group from 194.00 to 184.00 (P = 0.04). IgA and IgG levels were decreased during the study, and IgM increased in both groups. The results of this study indicate that consuming vegetable butter can have beneficial effects on the FBS and antibody levels, and prebiotic butter has better effects as it also controls the total cholesterol level. Iranian Registry of Clinical Trials (IRCT Id IRCT20160117026069N8 Registration date 03/12/2023).