Pistachio trees are wind-pollinated, with one male tree producing enough pollen for 25 nut-bearing females. Female trees produce their first nuts at about age five and can bear fruit for up to 200 years.
Calorie Reduction Without Restriction
According to James Painter, PhD, RD, Chair of the School of Family and Consumer Sciences at Eastern Illinois University, the “Pistachio Principle” is caloric reduction without calorie restriction. It is one of the many ways we can alter our environmental cues, allowing us to become more mindful and satisfied with our food choices.
In-shell Snack Slows Consumption
Dr. Painter completed two studies that found that individuals could reduce their overall calorie consumption without consciously restricting their diets. Interestingly, despite the reduction in calories, they reported feeling equally as satisfied as the control group that consumed more calories.
In his first study, individuals self-selected either in-shell or shelled pistachios. Because the shells act as a natural barrier, taking longer to remove, the in-shell group consumed 41% less than the shelled nut group. And yet they reported feeling equally as satisfied as the group consuming more.1
Pistachio Shell Offers Visual Cue
In Dr. Painter’s second study, in-shell pistachios were consumed over an 8-hour shift. On the first day the empty shells were left on the desks as a visual “reminder” of consumption and on the second day the shells were removed. Results showed that when the shells were removed immediately, subjects consumed 22% more calories.1
Stealth Dieting Tips and Tricks
Here are a few of Dr. Painter’s tips and tricks to help “fool yourself full.” You can find “The Pistachio Principle” fact sheet with more of Dr. Painter’s tips in Client Resources.
Buy smaller portionsFool yourself thin by buying single serve chips and small-size candy bars in place of family bags. Studies show that large package size increases caloric consumption by an average of 22 percent.
Consider environmental factors and choose meal companions wiselyBright light and fast music can encourage you to eat faster and ultimately consume more calories. Also, eating with friends generally increases the amount you eat.
Keep impulse foods out of sight and inaccessiblePut healthy snacks like nuts, fruits and vegetables in sight; and chocolate, candy and other unhealthy snacks in the cabinet.