Eating in-shell pistachios may significantly reduce a person's daily calorie intake. Research done at Eastern Illinois University found that consuming pistachios, which are good sources of fiber and protein, in that form can curb calorie intake by 41 percent.
Scientists conducted two studies to determine the benefits of the nut. The first discovered that participants who ate in-shell pistachios consumed 41 percent fewer calories than those who ate shelled pistachios. The second sought to determine why this was the case, and discovered that the pistachio shells provide "visual cues" that remind consumers how much they have been eating.
"In-shell pistachios are the original 'slow food.' The findings of these studies demonstrate that pistachios, as one of the only in-shell snack nuts, help slow consumption; and further, that the empty shells offer a visual cue, reducing calorie intake," said behavioral eating expert and study author, James Painter, Ph.D., R.D.
Along with possibly helping with weight loss, nuts like pistachios may also have other health benefits. Eating nuts can help lower "bad" cholesterol and may promote heart health.