Blood Lipid Responses to Diets Enriched with Cottonseed Oil Compared With Olive Oil in Adults with High Cholesterol in a Randomized Trial

Abstract

Background: Increasing unsaturated fat intake is beneficial for cardiovascular health, but the type of unsaturated fat to recommend remains equivocal.

Objectives: We investigated the effects of an 8-week diet intervention that was rich in either cottonseed oil (CSO; PUFA rich) or olive oil (OO; MUFA rich) on blood lipids in hypercholesterolemic adults.

Methods: Forty-three men and women with hypercholesterolemia (53 ± 10 years; BMI, 27.6 ± 4.8 kg/m2) completed this randomized parallel clinical trial consisting of an 8-week partial outpatient feeding intervention. Participants were given meals and snacks accounting for ∼60% of their daily energy needs, with 30% of energy needs from either CSO (n = 21) or OO (n = 22). At pre- and postdiet intervention visits, participants consumed a high-SFA meal (35% of total energy needs; 70% of energy from fat). The primary outcomes of fasting cholesterol profiles and secondary outcomes of postprandial blood lipids and glycemic markers were assessed over a 5-hour period.

Results: There were greater reductions from baseline to week 8 in fasting serum total cholesterol (TC; -17.0 ± 3.94 mg/dL compared with -2.18 ± 3.72 mg/dL, respectively; P = 0.008), LDL cholesterol (-19.7 ± 3.94 mg/dL compared with -5.72 ± 4.23 mg/dL, respectively; P = 0.018), non-HDL cholesterol (-20.8 mg/dL ± 4.00 compared with -6.61 ± 4.01 mg/dL, respectively; P = 0.014), and apoB (-11.8 mg/dL ± 2.37 compared with -3.10 ± 2.99 mg/dL, respectively; P = 0.05), in CSO compared with OO. There were also visit effects from baseline to week 8 for increases in HDL cholesterol (CSO, 56.5 ± 2.79 mg/dL to 60.2 ± 3.35 mg/dL, respectively; OO: 59.7 ± 2.63 mg/dL to 64.1 ± 2.24 mg/dL, respectively; P < 0.001), and decreases in the TC:HDL-cholesterol ratio (CSO, 4.30 ± 0.27 mg/dL to 3.78 ± 0.27 mg/dL, respectively; OO, 3.94 ± 0.16 mg/dL to 3.57 ± 0.11 mg/dL, respectively; P < 0.001), regardless of group assignment. In response to the high-SFA meal, there were differences in postprandial plasma glucose (P = 0.003) and triglyceride (P = 0.004) responses and a trend in nonesterified fatty acids (P = 0.11) between groups, showing protection in the postprandial state from an occasional high-SFA fat meal with CSO, but not OO, diet enrichment.

Conclusions: CSO, but not OO, diet enrichment caused substantial improvements in fasting and postprandial blood lipids and postprandial glycemia in hypercholesterolemic adults. This trial was registered at clinicaltrials.gov as NCT04397055.

Keywords: HDL cholesterol; LDL cholesterol; SCD1; cottonseed oil; high-fat diet; hypercholesterolemia; olive oil; stearoyl-CoA desaturase-1.

© The Author(s) 2022. Published by Oxford University Press on behalf of the American Society for Nutrition.

Figures

FIGURE 1

CONSORT flow diagram selection of participants.

FIGURE 2

Serum fasting (A) TC, (B) LDL cholesterol, (C) apoB, (D) non–HDL cholesterol, (E) TC:HDL-cholesterol ratio, and (F) HDL cholesterol from pre-, mid-, and postdiet intervention visits in adults with hypercholesterolemia (CSO, n = 21; OO, n = 22). Data were analyzed using a 2-way (treatment × visit) repeated-measures ANOVA. *Significant treatment × visit interaction (P < 0.001) and a difference from baseline at a P value < 0.05. ǂA trend for a treatment × visit interaction (P = 0.09) and a difference from baseline at a P value < 0.01. #Significant visit effect and a difference from baseline, regardless of group assignment, at a P value < 0.05. All values are presented as means ± SEMs. Preintervention visits were at week 0, midintervention visits at week 4, and postintervention visits at week 8. CSO, cottonseed oil; Mid, midintervention; OO, olive oil; Pre, preintervention; Post, postintervention; TC, total cholesterol.

FIGURE 3

Fasting biochemical markers of (A) plasma triglycerides, (B) plasma NEFAs, (C) serum LDL-P, (D) serum LDL medium, (E) plasma insulin, (F) plasma glucose, (G) serum HDL large, and (H) serum LDL small, from pre-, mid-, and postdiet intervention visits in adults with hypercholesterolemia (CSO, n = 21; OO, n = 22). Data were analyzed using a 2-way (treatment × visit) repeated-measures ANOVA. #Significant visit effect and a difference from baseline, regardless of group assignment, at a P value < 0.05. All values are presented as means ± SEMs. Preintervention visits were at week 0, midintervention visits at week 4, and postintervention visits at week 8. LDL-P, LDL particle number; Mid, midintervention; NEFA, nonesterified fatty acid; Pre, preintervention; Post, postintervention.

FIGURE 4

Time course for (A, B) plasma TGs, (C, D) NEFAs, (E, F) insulin, and (G, H) glucose for each treatment at pre- and postintervention visits in adults with hypercholesterolemia (CSO, n = 21; OO, n = 21). Participants consumed a high–saturated fat breakfast meal immediately after time 0. *Significant treatment × visit interaction and a difference between the pre- and postintervention meal responses within a group (P < 0.05). ǂTrend for treatment × visit interaction and a difference between the pre- and postintervention meal responses within a group (P = 0.10). All values are presented as means ± SEMs. Preintervention visits were at week 0 and postintervention visits were at week 8. CSO, cottonseed oil; NEFA, nonesterified fatty acid; OO, olive oil; Post, postintervention; Pre, preintervention; TG, triglyceride.