If the fecal fat losses associated with undigested pieces of nuts (due to inadequate chewing), and the tedium of shelling them in the first place, help account for why nuts don’t tend to lead to weight gain, then studies on nut butters would presumably turn out differently.
Testing the Pistachio Principle
Both the pistachio principle and the fecal excretion theory were put to the test recently, by studying the effects of peanut processing on body weight. Let’s feed a bunch of people a half cup of peanuts every day for a month, and another group we’ll feed the same amount of nuts—but we’ll grind them into peanut butter first.
So, half a cup of peanuts’ worth of peanuts, versus peanut butter. And, that was added on top of whatever else they were eating in their regular diet. So, calorie-wise, at the end of the month, they should have put on a few pounds.
Well, as we saw before, in the whole-nut peanut group, that just didn’t happen. But, that’s why we have the peanut butter group, right? Not a lot of shelling or crunching necessary with peanut butter. And, the cell walls of the peanuts were all ground up; all the oil released and made available for absorption. And, they didn’t go extra chunky; this was smooth peanut butter.
So, if the reason people don’t gain weight on nuts is because of all that chewing, or fecal fat loss, then the prediction would be that although the whole-nut group may not pile on the pounds, the peanut butter group definitely would. But, they didn’t. Neither group gained the expected weight.
The plot thickens. Next, we’ll explore the dietary compensation theory.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring watch the above video. This is just an approximation of the audio contributed by Kerry Skinner.
Please consider volunteering to help out on the site.
- Mattes RD, Dreher ML. Nuts and healthy body weight maintenance mechanisms. Asia Pac J Clin Nutr. 2010;19(1):137-41.
- McKiernan F, Lokko P, Kuevi A, Sales RL, Costa NM, Bressan J, Alfenas RC, Mattes RD. Effects of peanut processing on body weight and fasting plasma lipids. Br J Nutr. 2010 Aug;104(3):418-26.
Images thanks to Evan-Amos via Wikimedia Commons, and Newbirth35 via flickr
Both the pistachio principle and the fecal excretion theory were put to the test recently, by studying the effects of peanut processing on body weight. Let’s feed a bunch of people a half cup of peanuts every day for a month, and another group we’ll feed the same amount of nuts—but we’ll grind them into peanut butter first.
So, half a cup of peanuts’ worth of peanuts, versus peanut butter. And, that was added on top of whatever else they were eating in their regular diet. So, calorie-wise, at the end of the month, they should have put on a few pounds.
Well, as we saw before, in the whole-nut peanut group, that just didn’t happen. But, that’s why we have the peanut butter group, right? Not a lot of shelling or crunching necessary with peanut butter. And, the cell walls of the peanuts were all ground up; all the oil released and made available for absorption. And, they didn’t go extra chunky; this was smooth peanut butter.
So, if the reason people don’t gain weight on nuts is because of all that chewing, or fecal fat loss, then the prediction would be that although the whole-nut group may not pile on the pounds, the peanut butter group definitely would. But, they didn’t. Neither group gained the expected weight.
The plot thickens. Next, we’ll explore the dietary compensation theory.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring watch the above video. This is just an approximation of the audio contributed by Kerry Skinner.
Please consider volunteering to help out on the site.
- Mattes RD, Dreher ML. Nuts and healthy body weight maintenance mechanisms. Asia Pac J Clin Nutr. 2010;19(1):137-41.
- McKiernan F, Lokko P, Kuevi A, Sales RL, Costa NM, Bressan J, Alfenas RC, Mattes RD. Effects of peanut processing on body weight and fasting plasma lipids. Br J Nutr. 2010 Aug;104(3):418-26.
Images thanks to Evan-Amos via Wikimedia Commons, and Newbirth35 via flickr
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Testing the Pistachio Principle
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Content URLDoctor's Note
This is the third of a seven-part video series on a fascinating phenomenon: why don’t nuts make us fat? I reviewed the balance of evidence in Nuts and Obesity: The Weight of Evidence, and introduced two theories in Solving the Mystery of the Missing Calories. Next, we hit Testing the Dietary Compensation Theory, and then, Testing the Fat-Burning Theory.
For more context, check out my associated blog posts: Nuts Don’t Cause Expected Weight Gain; and The Best Nutrition Bar.
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