Pistachio is another food item that people generally ignore as it is a nut but the fact is it helps a lot to reduce more amount of weight. The reason people ignore this is that it is a common belief that intake of nuts will increase fat content in the body. Of course that is true but it is for nuts like cashew. As far as pistachio is considered it is rich in potassium and anti-oxidant and hence you will shed pounds of weight in few weeks of time. Anti-oxidant generally will burn the fat more quickly by increasing metabolism. Total calories per 100g serving: 394.