Oil Consumption and Cholesterol

University of Georgia112 enrolled

Overview

More than 31 million U.S. adults have high total cholesterol and over 73 million U.S. adults have high LDL cholesterol. Cottonseed oil (CSO) is found readily in our food supply, and recent research has shown improvements in blood lipids following CSO consumption in healthy adults with normal cholesterol profiles. To date, however, there are no published studies on the effects of CSO-enriched diets on blood lipids and markers of health in an older population with hypercholesterolemia. Therefore, the purpose of this study is to test the health effects of a diet rich in CSO against a diet rich in olive oil to determine if the CSO-enriched diet will show greater improvements in blood lipids and other health markers in adults with high cholesterol levels. If CSO in the diet is found to improve these markers, these study findings could lead to improvements in health.

This was a single-blind, randomized controlled trial. Investigators recruited subjects with hypercholesterolemia (high blood cholesterol levels). Subjects were randomized into one of two groups: (1) Cottonseed oil (CSO), (2) Olive oil (OO). The interventions consist of identical foods that are only different in the respective oil they are prepared with. There was a screening visit and 3 testing visits: Baseline (visit 2), mid-visit at week 4 (visit 6), and post-visit at week 8 (visit 10). Anthropometrics, questionnaires, and a fasting blood sample were collected at each visit. At visits 2 and 10 participants participated in a saturated fatty acid meal challenge in which additional blood and metabolism measurements were collected. Visits 3-9 represent weekly meal pickups, with the exception of visit 6 which is also a testing visit. Hypothesis: Investigators hypothesized that enrichment of the diet with CSO would result in significantly greater improvements in blood lipids, metabolism, and appetite compared to the OO group.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Eligibility

Sex: ALLMin age: 30 YearsMax age: 75 Years

Medical Language ↔ Plain English

Inclusion Criteria: * 30-75 year old * body mass index (BMI) between 18.5-39.9 kg/m2 * higher cholesterol levels indicated by "At Risk/Borderline High" in two or more of the variables (total cholesterol: 180-239 mg/dL, LDL cholesterol 110-159 mg/dL, triglycerides 130-199 mg/dL) or "High" in either total cholesterol (240 mg/dL and higher) or LDL (160 mg/dL or higher), and having triglyceride levels less than 350mg/dL. Exclusion Criteria: * participants with familial hypercholesterolemia * LDL levels greater than the 95th percentile based on age and sex * HDL levels lower than the 20th percentile based on age and sex * women on hormone replacement therapy for less than 2 years * individuals who regularly exercise more than 3 h/w * weight gain or loss more than 5% of their body weight in the past 3 months * plans to begin a weight loss/exercise regiment during the trial * history of medical or surgical events that could affect digestion or swallowing * gastrointestinal surgeries * conditions or disorders * any chronic or metabolic diseases * atherosclerosis * previous MI or stroke * cancer * fasting blood glucose levels greater than 126 mg/dL * blood pressure greater than 180/120 mmHg * medication use affecting digestion and absorption * medication use affecting metabolism (e.g. thyroid meds) * lipid-lowering medications * medications for diabetes * steroid/hormone therapies * a medically prescribed or special diet * food allergies (specific for the foods made in the study) * taking fish oil and calciumfloroboron supplements * excessive alcohol use (greater than 3 drinks/d for men; greater than 2 drinks/d for women) * tobacco or nicotine use

Outcomes

Primary Outcomes

Change in baseline fasting blood lipids at weeks 4 and 8

Total Cholesterol (mg/dL), high-density lipoprotein (HDL) cholesterol (mg/dL), triglycerides (mg/dL), low-density lipoprotein (LDL) cholesterol (mg/dL), apolipoprotein B (mg/dL)

Time frame: Baseline, 4 weeks, 8 weeks

Change in baseline lipoprotein (a), lipoprotien particle number and size at weeks 4 and 8

Low density lipoprotien (LDL) particle number (nmol/L), LDL small (nmol/L), HDL large (nmol/L), LDL medium (nmol/L), lipoprotein (a) (nmol/L).

Time frame: Baseline, 4 weeks, 8 weeks

Change in baseline low density lipoprotien (LDL) peak size at weeks 4 and 8

LDL peak size (angstrom)

Time frame: Baseline, 4 weeks, 8 weeks

Secondary Outcomes

Change in Baseline Blood Concentration of Hunger and Satiety Hormones over 8 weeks

Blood samples will be collected to measure Peptide tyrosine tyrosine (YY) (pg/mL), Cholecystokinin (CCK) (pg/mL), Ghrelin (pg/mL), Glucagon-like peptide 1 (GLP1) (pg/mL)

Time frame: measured at weeks 1 and 8 at fasting and for 5 hours postprandially

Change in Height over 8 weeks

Height measured in centimetres