1. OmniHeart Feeding Study
Presented at
The American Heart Association
Scientific Session 2005
Presented by Dr. Lawrence J. Appel

2. OmniHeart Feeding Study: Background
A diet rich in carbohydrates that emphasizes fruits, vegetables, and low-fat dairy products, while minimizing sodium intake, saturated fat, total fat, and cholesterol could substantially lower blood pressure (DASH trials).
Presented at AHA 2005

3. OmniHeart Feeding Study: Study Design
161 patients age >30 years; systolic blood pressure mmHg or diastolic blood pressure mmHg
45% female, mean age 53.6 years, 930 patients screened
Randomized. Crossover.
Standard DASH Diet
Standard carbohydrates (58%), protein (15%), fat (27%)
Protein Modified
DASH Diet
carbohydrates (48%), protein (25%), fat (27%)
Unsaturated Fat Modified DASH Diet
carbohydrates (48%), protein (15%), fat (37%)
monounsat. (21%), polyunsat. (10%), sat. (6%)
Patients were on assigned diet for 6 weeks, where they ate prepared meals on-site during weekdays and ate prepared meals off-site during weekends. Following 6 week diet period, participants ate their own food for 2-4 weeks, after which time participants crossed over to the next diet.
Primary Endpoint: Systolic blood pressure and LDL cholesterol at the end of each diet period.
Secondary Endpoint: Diastolic blood pressure, trigylcerides, and HDL cholesterol at the end of each diet period.
Presented at AHA 2005

4. OmniHeart Feeding Study: Weight
Measured weight at the end of each diet period (kg)
Mean baseline BMI was 30.2 kg/m2 and weight was 87.3 kg
Weight did not change with the different diets (86.3 kg vs 86.0 kg vs 86.7 kg) kg
Presented at AHA 2005

5. OmniHeart Feeding Study : Primary Endpoint
Systolic blood pressure (mmHg)
Systolic blood pressure was reduced with all three diets, but the reduction was greater among the protein diet (-9.5 mmHg; p=0.002) and unsaturated fat diet (-9.3 mmHg; p=0.005) compared with the carbohydrate diet (-8.2 mmHg)
Standard carbohydrate
Protein modified
Unsaturated fat modified
mmHg
Presented at AHA 2005

6. OmniHeart Feeding Study : Primary Endpoint
LDL (mg/dL)
LDL reductions were greater with the protein diet (-14.2 mg/dL, p=0.01) and non-significantly with the unsaturated fat diet (-13.1 mg/dL, p=0.20) compared with the carbohydrate diet (-11.6 mg/dL)
Standard carbohydrate
Protein modified
Unsaturated fat modified
mg/dL
Presented at AHA 2005

7. OmniHeart Feeding Study : Secondary Endpoint
Diastolic blood pressure (mmHg)
Diastolic blood pressure was reduced with all three diets, but the reduction was greater among the protein diet (-5.2 mmHg; p<0.001) and unsaturated fat diet (-4.8 mmHg; p=0.02) compared with the carbohydrate diet (-4.1 mmHg)
Standard carbohydrate
Protein modified
Unsaturated fat modified
mmHg
Presented at AHA 2005

8. OmniHeart Feeding Study : Secondary Endpoint
Trigylcerides (mg/dL)
Triglyceride levels were reduced among the protein diet (-16.4 mg/dL; p<0.05) and unsaturated fat diet (-9.3 mg/dL; p<0.05) compared with the carbohydrate diet (+0.1 mg/dL)
Protein modified
Unsaturated fat modified
Standard carbohydrate
mg/dL
Presented at AHA 2005

9. OmniHeart Feeding Study : Total Cholesterol
Total cholesterol (mg/dL)
Total cholesterol was reduced with all three diets, but the reduction was greater among the protein diet (-19.9 mg/dL; p<0.05) and unsaturated fat diet (-15.4 mg/dL; p<0.05) compared with the carbohydrate diet (-12.4 mg/dL)
Standard carbohydrate
Protein modified
Unsaturated fat modified
mg/dL
Presented at AHA 2005

10. Estimated 10 year coronary heart disease risk (%)
OmniHeart Feeding Study : Estimated 10 Year Coronary Heart Disease Risk (based on the Framingham risk score)
Estimated 10 year coronary heart disease risk (%)
Estimated 10 year coronary heart disease risk based on the Framingham risk score was lowered by 16% for the carbohydrate diet, 21% for the protein diet, 20% for the unsaturated fat diet.
Standard carbohydrate
Protein modified
Unsaturated fat modified %
Presented at AHA 2005

11. OmniHeart Feeding Study: Limitations
Neither the protein nor the fat diet can be advocated over the other because both results showed similar risk scores
Future trials should consider the following:
A fat modified diet with a greater emphasis on polyunsaturated fats.
A focus on weight loss, instead of maintaining study participants at the same weight.
A closer look into different fiber, protein, and carbohydrate sources and their cumulative effect on risk score.
Presented at AHA 2005

12. OmniHeart Feeding Study: Summary
Among individuals with hypertension or prehypertension, use of a modified reduced carbohydrate DASH diet was associated with greater reductions in blood pressure and lipid parameters compared with use of the standard DASH diet.
The DASH diet, which is low in saturated and total fat, has been shown in previous randomized trials to be effective for reducing blood pressure and lipid parameters. However, a substantial portion of the DASH diet is made up of carbohydrates. The present study confirms the blood pressure and lipid reductions found in earlier trials with the standard DASH diet, but also showed additional reductions are possible by substituting more protein or unsaturated fats for some of the carbohydrates.
It should be noted that the trial was conducted in a controlled manner in which all weekday meals were prepared and consumed on-site. Weight was maintained at a stable level in order to remove possible confounding of weight loss on the interpretation of the effect of the diet modification on the results.
Presented at AHA 2005