Final answer:
The Mediterranean diet was associated with the lowest risk of heart disease in Dr. Ancel Keys's Seven Countries Study, due to its high intake of plant-based foods and olive oil, and low consumption of meats and saturated fats.
Step-by-step explanation:
In Dr. Ancel Keys's landmark Seven Countries Study, the Mediterranean diet, particularly noted in countries like Greece and Italy, was associated with the lowest risk of heart disease. This diet pattern is characterized by a high consumption of fruits, vegetables, and olive oil, along with a low intake of meats and saturated fats. The benefits of the Mediterranean diet go beyond improving cardiovascular health, also including better blood cholesterol levels and overall longevity.
The study highlighted how lifestyle and diet play a crucial role in the incidence of chronic diseases such as heart disease, which led to a greater exploration into healthy eating habits. The Mediterranean diet continues to be highly recommended and holds up in modern research studies, as evidenced by a recent study indicating a 25 percent lower risk of developing cardiovascular disease among women following this diet over a 12-year period.