Dietary Carbohydrate Type and Cardiovascular Disease (CVD) Risk Indicators

Dietary Carbohydrate Type and CVD Risk Indicators

The aim of this study is to determine the effect of habituation to diets with different types of carbohydrate (simple-carb, refined-carb, unrefined-carb) on selected Cardiovascular Disease (CVD) risk indicators.

The objective of this pilot study is to determine the relative comparability for an isocaloric exchange of (1) refined-carb for simple-carb and (2) refined-carb for unrefined-carb, on established and emerging CVD risk indicators. To achieve this goal, subjects with moderate dyslipidemia (LDL cholesterol > 100mg/dL) will consume diets enriched in 3 types of carbohydrate (simple-carb, refined-carb and unrefined-carb) according to a randomized, cross-over design.

Inclusion Criteria:

• LDL cholesterol (>100 mg/dL)
• > 50 years (all females postmenopausal, as defined by complete natural cessation of menses for > 12 months or a bilateral oophorectomy)
• BMI > 25 and < 35 kg/m2
• Normal kidney function as assessed by serum creatinine and blood urea nitrogen
• Normal liver function as assessed by serum glutamic oxaloacetic transaminase and alkaline phosphatase
• Normal thyroid function as assessed by serum thyroid stimulating hormone concentrations
• Normal gastrointestinal function
• Fasting plasma glucose concentrations < 120 mg/dL
• Normotensive with or without medication
• Non-smoker for at least 12 months
• Alcohol intake of less than 7 drinks per week
• Consistent physical activity pattern

Exclusion Criteria:

• < 50 years old

• BMI < 25 and > 35 kg/m2

• LDL cholesterol <100 mg/dL

• Abnormal fasting plasma glucose levels >120 mg/dL

• Use of medications known to affect lipid metabolism:

  • Bile Acid Sequestrants (Cholestyramine, Colestipol, Colesevelam, etc.)
  • Cholesterol Absorption Inhibitors (Ezetimibe [Zetia])
  • Nicotinic Acid Agents (Niacin, Niacor, Slo-Niacin, etc)
  • Fibrates (Gemfibrozil [Lopid], Ciprofibrate, Fenofibrate [Tricor], etc)
  • Probucol

• Use of anticoagulants (Coumadin, Heparin, Plavix, etc), anabolic steroids, and hydrocortisone

• Use of hormone therapy medications containing estrogen

• Use of fish oil / omega-3 supplements, and Metamucil (or fiber containing dietary supplements)

• Any Aspirin, non-steroidal anti-inflammatory drugs (NSAID) or antihistamine use or therapies that cannot be discontinued by subject for 72 hours prior to blood draws and adipose tissue collection and any NSAIDS for 72 hours after the procedure for obtaining adipose tissue sample

• Established cardiovascular disease as defined by history of myocardial infarction, stroke, heart failure, coronary artery bypass graft, stenosis >50%, angina and peripheral arterial disease

• Uncontrolled hypertension or high blood pressure reading at the discretion of the study physician or nurse

• Renal or kidney disease, as defined by a history of chronic kidney disease or by glomerular filtration rate of < 60 ml.min/1.73 m2 calculated from screening blood tests

• Liver disease, as defined by a history of chronic hepatitis B or C, cholestatic or cirrhotic liver disease, nonalcoholic fatty liver disease, elevations of serum glutamic-pyruvic transaminase (SGPT) or serum glutamic oxaloacetic transaminase (SGOT) greater than 1.5 times the upper limit of normal at screening, bilirubin greater than 2 mg/dL (in the absence of benign causes of elevated bilirubin such as Gilbert's syndrome) at screening, or albumin below the lower limit of normal

• Hypothyroidism or hyperthyroidism, defined as screening TSH outside of normal ranges (<0.4 or >4.5), unless controlled with medication for at least 6 months

• Type I and II diabetes

• Gastrointestinal disease

• Lidocaine Allergy

• Smoking within the past 12 months.

• Alcohol intake > 7 drinks per week or unwillingness to not consume alcohol while participating in the study

• Unwillingness to maintain body weight during participation in the study

• Unwillingness to adhere to diet and study protocol

• Weight gain or loss of more than 15 lb within 6 months prior to enrollment

• Non-English speaking subjects

• No Social Security number

• Food allergies or aversions

• Blood donation within the past 8 weeks