Because I eat a big bag of cashews for lunch on Mondays, I try to stay away from nuts the rest of the week. But now I wonder if I shouldn’t be eating nuts more often.
The conventional wisdom is that yes, nuts are good for you, but because they’re so high in calories – and it’s so hard to restrain yourself to a single small serving – they’re a dangerous thing to snack on.
And yet study after study shows that people who eat nuts regularly tend to be healthier and weigh less than those who don’t. Nut eaters are not only less likely to develop heart disease, metabolic syndrome and Type 2 diabetes, according to this 2011 study in the Journal of the American College of Nutrition, but they’re less likely to die – of any cause – during a given period than non-nut eaters, according to this 2013 study in the New England Journal of Medicine.
My Monday experimentation surely involves a much larger nut portion – typically 6-8 ounces — than any of these studies. And yet I almost always weigh less the following morning, probably because I’m so satisfied that I just don’t eat much the rest of the day.
I think what I might do is allow myself to eat only nuts in the shell on other days. Though I was unable to find a number on this, it stands to reason that you burn a few calories during the nut-cracking process. Another study — this one by Dr. James Painter of Eastern Illinois University, producer of the Portion-Size Me video in which graduate students lost weight eating fast food for a month – showed that people who were given pistachios in the shell ate less than those given naked nuts, but were just as satisfied afterward.
Painter calls this “the Pistachio Principle,” and he says in his study, published in the journal Appetite, that test subjects tended to grab the same-size handful of nuts whether they were in the shell or not. The shell group, allowed to take as much as they wanted, ate 125 calories worth while the naked nut group consumed 211 calories.
In a related study, Painter found that people given a bowl of in-shell pistachios on their office desk ate less during their work shift when the empty shells were left in view than those whose shell casings were removed every 2 hours. The empty shells provided a visual cue of how much they’d already eaten, apparently.