One group assigned to a Mediterranean diet was given extra-virgin olive oil each week and was instructed to use at least 4 four tablespoons a day. The other group got a combination of walnuts, almonds and hazelnuts and was instructed to eat about an ounce of the mix each day. An ounce of walnuts, for example, is about a quarter cup — a generous handful. The mainstays of the diet consisted of at least three servings a day of fruits and at least two servings of vegetables. Participants were to eat fish at least three times a week and legumes, which include beans, peas and lentils, at least three times a week. They were to eat white meat instead of red, and, for those accustomed to drinking, to have at least seven glasses of wine a week with meals.