The Optimal Macronutrient Intake Trial for Heart Health (OmniHeart) study compared the effects of three heart-healthy diets, all based on the Dietary Approaches to Stop Hypertension diet — one emphasized carbohydrates, another emphasized protein, and the third emphasized unsaturated fat. Although all three lowered blood pressure and improved cholesterol and triglyceride levels, the higher-protein and higher-unsaturated-fat diets worked best.
The general plan for all three diets looked like this:

  • Eat 1-2 servings of fruit at every meal and have an extra fruit at breakfast.
  • Have 2-3 servings of vegetables at lunch and dinner.
  • Create a fruit and nut trail mix for snacks: 1/2 cup dried fruit with 1 oz. unsalted nuts.
  • Each day have a serving of fat-free or low-fat milk and milk product (milk, yogurt, cheese) at two meals and occasionally at a third meal or snack.
  • Use whole grains rather than refined grains as often as possible.
  • Select lean versions of meats and remove skin from poultry.

The breakdown of calories and nutrients in the three OmniHeart diets are listed in the table below.
Food group Servings per day
� Higher carbohydrate diet Higher protein diet Higher unsaturated fat diet
Fruit and juices (� cup) 6.6 3.8 4.8
Vegetables (� cup) 4.4 5.4 6.3
Grains, mostly whole grains (1 oz or � cup) 5.3 5.0 4.3
Milk and milk products (1 cup) 2.1 2.5 1.9
Legumes, nuts, seeds, other vegetable protein (1 oz meat-equivalents) 1.3 3.0 1.2
Beef, pork, ham (1 oz) 0.9 1.1 1.0
Poultry (1 oz) 1.6 2.6 1.8
Fish (1 oz) 1.1 1.3 1.0
Egg product substitutes
(1 oz meat-equivalents)		 0.2 1.1 0.1
Desserts and sweets (tsp sugar) 4.6 2.5 1.7
Fats and oils (tsp) 6 3.5 12
Nutrient targets Percent of daily calories
� Higher carbohydrate diet Higher protein diet Higher unsaturated fat diet
Carbohydrates 58 48 48
Total fat 27 27 37
Monounsaturated fat 13 13 21
Protein 15 25 15