Cardiologist’s verdict: the best diet for your heart (and the one to avoid) Professor Jason Kovacic, leading cardiologist and Institute Director, rates popular diets from best to worst for heart health, giving Mediterranean a perfect 10/10 and carnivore just 1/10. New Delhi:If you’re trying to eat healthy but feel confused by the endless diet trends, you’re not alone. In an Instagram video, Professor Kovacic graded popular diets from best to worst for heart health, awarding the Mediterranean diet a 10/10 while criticising the carnivore diet as one of the worst options at just 1/10. Worst diet for heart healthThe cardiologist was honest regarding the carnivore diet, rating it only 1/10 for heart health. Carnivore diet (1/10):High in saturated fat and zero fibre, making it risky for cholesterol and gut health.