While all nuts are healthy (eg. rich in vitamin E, protective heart benefits, contain the "good" unsaturated fat), they are very high in calories and the aforementioned fat.

But nuts can be a part of any diet -- just watch the portions and avoid those that are roasted in oil, salt, etc. Usually, a small handful a day, or one cup per week, of nuts is recommended.

Walnuts, peanuts, and almonds are some examples that are good... Macadamias, pistachios, and cashews have more calories from fat than other nuts. The key is moderation.