Effect of Amount and Type of Dietary Carbohydrates on Risk for Cardiovascular Heart Disease and Diabetes

NCT00608049 | Completed DMC

• 2 other identifiers: 481R01HL084568
• Study Type: interventional
• Target: 189
• Locations: 1 country
• Sites: 2

Brief Summary

Cardiovascular disease (CVD) and diabetes are health conditions that are strongly influenced by a person's diet. Although the best diet to prevent CVD and diabetes is uncertain, reducing intake of saturated and transunsaturated fats is known to help lower cardiovascular risk. However, even diets low in these fats can vary widely in other energy providing nutrients, particularly carbohydrates. This study will determine the effects of a higher versus lower carbohydrate diet, each with a high or low glycemic index (GI) composition, on risk factors for CVD and diabetes.

Conditions

Overweight; Cardiovascular Diseases

Keywords

Blood Pressure; Diabetes; Nutrition; Dietary Carbohydrate; Lipoproteins; Insulin Resistance

Outcome Measures

Primary Outcomes (1)

• Systolic blood pressure (SBP), Low Density Lipoproteins (LDL) cholesterol, High Density Lipoproteins (HDL) cholesterol, triglycerides, and insulin sensitivity

  Measured at Week 5 of each dieting period

Secondary Outcomes (3)

• Diastolic blood pressure (DBP); apolipoproteins B, CIII, A-I, and Very Low Density Lipoproteins (VLDL); and LDL with apolipoprotein CIII

  Measured at Week 5 of each dieting period

• Beta cell response, glucose effectiveness, and fructosamine; postprandial glucose, insulin, lipids, and hormone levels

  Measured at Week 5 of each dieting period

• Overall CVD risk using risk equations

  Measured at Week 5 of each dieting period

Study Arms (8)

1

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: high carbohydrate/high GI, high carbohydrate/low GI, low carbohydrate/high GI, and low carbohydrate/low GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

2

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: high carbohydrate/high GI, high carbohydrate/low GI, low carbohydrate/low GI, and low carbohydrate/high GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

3

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: high carbohydrate/low GI, high carbohydrate/high GI, low carbohydrate/high GI, and low carbohydrate/low GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

4

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: high carbohydrate/low GI, high carbohydrate/high GI, low carbohydrate/low GI, and low carbohydrate/high GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

5

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: low carbohydrate/high GI, low carbohydrate/low GI, high carbohydrate/high GI, and high carbohydrate/low GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

6

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: low carbohydrate/high GI, low carbohydrate/low GI, high carbohydrate/low GI, and high carbohydrate/high GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

7

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: low carbohydrate/low GI, low carbohydrate/high GI, high carbohydrate/high GI, and high carbohydrate/low GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

8

EXPERIMENTAL

Participants will follow four diet plans, each for a period of 5 weeks, in the following order: low carbohydrate/low GI, low carbohydrate/high GI, high carbohydrate/low GI, and high carbohydrate/high GI

Behavioral: High carbohydrate and low glycemic index (GI) diet; Behavioral: Low carbohydrate and low GI diet; Behavioral: High carbohydrate and high GI diet; Behavioral: Low carbohydrate and high GI diet

Interventions

High carbohydrate and low glycemic index (GI) diet BEHAVIORAL

The high carbohydrate and low GI diet will require 58% of daily calories to be from carbohydrates and will be composed of meals with a GI of less than 45 on the glucose scale.

1; 2; 3; 4; 5; 6; 7; 8

Low carbohydrate and low GI diet BEHAVIORAL

The low carbohydrate and low GI diet will require 40% of daily calories to be from carbohydrates and will be composed of meals with a GI of less than 45 on the glucose scale.

1; 2; 3; 4; 5; 6; 7; 8

High carbohydrate and high GI diet BEHAVIORAL

The high carbohydrate and high GI diet will require 58% of daily calories to be from carbohydrates and will be composed of meals with a GI of greater than 65 on the glucose scale.

1; 2; 3; 4; 5; 6; 7; 8

Low carbohydrate and high GI diet BEHAVIORAL

The low carbohydrate and high GI diet will require 40% of daily calories to be from carbohydrates and will be composed of meals with a GI of greater than 65 on the glucose scale.

1; 2; 3; 4; 5; 6; 7; 8

Eligibility Criteria

• Age: 30 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• SBP of 120 to 159 mmHg and DBP less than 100 mmHg at study entry (mean over three screening visits) (note: participants with stage 2 hypertension \[SBP greater than 160 mmHg or DBP greater than 100 mmHg\] based on the mean over three screening visits will be excluded, as will participants with a mean SBP greater than 170 mmHg or DBP greater than 105 mmHg at any one visit)
• Overweight or obese, as defined by a body mass index (BMI) greater than 25 kg/m2
• Willing to eat at least one on-site meal per day, 5 days per week, and willing to eat study diets and nothing else during controlled feeding periods

You may not qualify if:

• Symptomatic ischemic heart disease (e.g., angina pectoris)
• Regular use of medications that raise or lower BP during the 2 months prior to study entry
• Use of a lipid lowering agent in the 3 weeks prior to study entry
• Unstable dose of hormone replacement therapy, thyroid hormone replacement therapy, and psychotropic medications known to cause weight gain or affect the outcome variables (unstable is defined as a change in dose within 2 months of study entry)
• Use of insulin, oral hypoglycemic agent, lithium, oral corticosteroid, anti-psychotic drugs, weight loss medications, nitrate, or digitalis
• Active or prior CVD (e.g., stroke, heart attack, percutaneous transluminal coronary angioplasty, coronary artery bypass graft, congestive heart failure, symptomatic ischemic heart disease \[angina\], or arteriosclerotic cardiovascular disease-related therapeutic procedure)
• Diabetes mellitus
• Cancer diagnosis or treatment in the 2 years prior to study entry (note: people with non-melanoma skin cancer, localized breast cancer, or localized prostate cancer can enroll if they did not require systemic chemotherapy)
• Active inflammatory bowel disease, malabsorption, or major gastrointestinal resection
• Renal insufficiency as determined by a serum creatinine greater than 1.2 mg/dL for women or greater than 1.4 mg/dL for men (these participants can enroll if their estimated glomerular filtration rate is greater than 40 mL/min by either the Cockcroft-Gault equation or the simplified Modification of Diet in Renal Disease equation)
• Emergency room visit or hospital stay for asthma or chronic obstructive pulmonary disease in the 6 months prior to study entry
• Any serious illness not otherwise specified that would interfere with participation
• Fasting LDL cholesterol greater than 220 mg/dL and triglycerides greater than 750 mg/dL
• Fasting blood glucose greater than 125 mg/dL
• Serum transaminase greater than 2 times the upper range of normal, or a clinical diagnosis of hepatitis

Sponsors & Collaborators

• Brigham and Women's Hospital: lead
• National Heart, Lung, and Blood Institute (NHLBI): collaborator

Study Sites (2)

Johns Hopkins Medical Institutions

Baltimore, Maryland, 21205, United States

Location

Harvard T. H. Chan School of Public Health

Boston, Massachusetts, 02215, United States

Location

Related Publications (6)

• Wu Y, Juraschek SP, Hu JR, Mueller NT, Appel LJ, Anderson CAM, Miller ER. Higher Carbohydrate Amount and Lower Glycemic Index Increase Hunger, Diet Satisfaction, and Heartburn in Overweight and Obese Adults in the OmniCarb Randomized Clinical Trial. J Nutr. 2021 Aug 7;151(8):2477-2485. doi: 10.1093/jn/nxab128.

  PMID: 34049396 DERIVED

• Hu JR, Wu Y, Sacks FM, Appel LJ, Miller Iii ER, Young JH, Juraschek SP. Effects of carbohydrate quality and amount on plasma lactate: results from the OmniCarb trial. BMJ Open Diabetes Res Care. 2020 Aug;8(1):e001457. doi: 10.1136/bmjdrc-2020-001457.

  PMID: 32868311 DERIVED

• Juraschek SP, Miller ER 3rd, Selvin E, Carey VJ, Appel LJ, Christenson RH, Sacks FM. Effect of type and amount of dietary carbohydrate on biomarkers of glucose homeostasis and C reactive protein in overweight or obese adults: results from the OmniCarb trial. BMJ Open Diabetes Res Care. 2016 Nov 14;4(1):e000276. doi: 10.1136/bmjdrc-2016-000276. eCollection 2016.

  PMID: 27933186 DERIVED

• Juraschek SP, Chang AR, Appel LJ, Anderson CA, Crews DC, Thomas L, Charleston J, Miller ER 3rd. Effect of glycemic index and carbohydrate intake on kidney function in healthy adults. BMC Nephrol. 2016 Jul 8;17(1):70. doi: 10.1186/s12882-016-0288-5.

  PMID: 27391484 DERIVED

• Juraschek SP, McAdams-Demarco M, Gelber AC, Sacks FM, Appel LJ, White KJ, Miller ER 3rd. Effects of Lowering Glycemic Index of Dietary Carbohydrate on Plasma Uric Acid Levels: The OmniCarb Randomized Clinical Trial. Arthritis Rheumatol. 2016 May;68(5):1281-9. doi: 10.1002/art.39527.

  PMID: 26636424 DERIVED

• Sacks FM, Carey VJ, Anderson CA, Miller ER 3rd, Copeland T, Charleston J, Harshfield BJ, Laranjo N, McCarron P, Swain J, White K, Yee K, Appel LJ. Effects of high vs low glycemic index of dietary carbohydrate on cardiovascular disease risk factors and insulin sensitivity: the OmniCarb randomized clinical trial. JAMA. 2014 Dec 17;312(23):2531-41. doi: 10.1001/jama.2014.16658.

  PMID: 25514303 DERIVED

MeSH Terms

Conditions

Overweight; Cardiovascular Diseases; Diabetes Mellitus; Insulin Resistance

Interventions

Diet

Condition Hierarchy (Ancestors)

Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Hyperinsulinism

Intervention Hierarchy (Ancestors)

Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Study Officials

• Frank M. Sacks, MD

  Harvard University

  PRINCIPAL INVESTIGATOR

• Lawrence J. Appel, MD

  Johns Hopkins Medical Institutions, Baltimore

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Frank M. Sacks, MD

Study Record Dates

• First Submitted: January 23, 2008
• First Posted: February 6, 2008
• Study Start: February 1, 2008
• Primary Completion: February 1, 2011
• Study Completion: February 1, 2011
• Last Updated: July 6, 2016

Record last verified: 2016-07

Locations

US (2)