Worried about eating too many nuts in fear of gaining weight? Relax, as new research suggests you may be able to have a few extra handfuls without undoing all of your hard work.
Almonds are considered the nut to eat when on any weight loss diet. Most of us by now have heard of the 'almond mystery’, a mystery that people can eat copious amounts of almonds without putting weight on. Sound too good to be true? Well, let’s take a look.
One study  looked at the effect of consuming an additional intake of 320kcals from almonds, and the affect it had on body weight. Over a 6 month period, eighty-one male and female subjects were asked to eat an additional 320kcals from almonds and to keep their current diet the same. The results showed that after 6 months, "it did not lead on average to statistically or biologically significant changes in body weight despite an increase of 40%-50% in the ratio of unsaturated/saturated fat intake."
How is this possible?
The researchers from the study hypothesized that because the subjects were aware they were eating the additional calories, that they dispelled these calories by reducing caloric intake from other foods.
Researchers from the US Department of Agriculture think they've solved the puzzle. An average handful of almonds is worth at least 150kcals but the researchers believe you don't absorb anything like all the calories that almonds contain. The researchers started by giving 18 test subjects a standard diet for 18 days, followed by a diet that was supplemented by 42g almonds each day for 18 days, and finally a diet supplemented by 84g almonds for another 18 days. Their findings showed you only absorb 68 percent of the energy that the nutrition table suggests, is present in almonds .
The researchers write:
"When an 84g serving of almonds was incorporated into the diet daily, the energy digestibility of the diet as a whole decreased by 5 percent. Therefore, for individuals with energy intakes between 2000 and 3000 kcal/day, incorporation of 84 g almonds into the diet daily in exchange for highly digestible foods would result in a reduction of available energy of 100–150 kcal/day."
The amount of calories printed on the nutrition label is, in effect, overestimated by 32%. This means, if you like your almonds and consume 300kcals daily, you only really absorb 204kcals, leaving you with a 'phantom' 94kcals to play with. That said, the test was conducted using whole almonds. The study mentioned nothing about ground almonds and I imagine the energy uptake from ground almonds is considerably higher, leading to a greater caloric uptake.
Prefer pistachio nuts to almonds?
The researchers conducted a similar study using pistachio nuts, however, the results weren't as attractive, as subjects absorbed 95 percent of the energy contained in the pistachio nuts . Best stick to almonds.
This wouldn’t be the first example where nutrition labels have been wrong. It’s been shown that some overestimated the amount of calories a food is presumed to contain, showing an average of 8 percent more calories than the labels indicate . Studies like these begin to question the accuracy of the Atwater system (a system that calculates the available energy of foods) and whether its accuracy of calculating the available energy from foods needs to be reevaluated.
Until such a time, I wouldn’t hesitate to have the occasional handful of almonds without worrying about weighing them out! After all, you’ll probably be undershooting anyway, as long as you’re sensible and don’t go nuts! – Sorry, I couldn’t help myself!
 Hollis J, Mattes R. Effect of chronic consumption of almonds on body weight in healthy humans. Br J Nutr. 2007;98(3):651-6.
 Novotny JA, Gebauer SK, Baer DJ. Discrepancy between the Atwater factor predicted and empirically measured energy values of almonds in human diets. Am J Clin Nutr. 2012;96(2):296-301. doi: 10.3945/ajcn.112.035782.
 Baer DJ, Gebauer SK, Novotny JA. Measured energy value of pistachios in the human diet. Br J Nutr. 2012;107(1):120-5. doi: 10.1017/S0007114511002649.
 Urban LE, Dallal GE, Robinson LM, Ausman LM, Saltzman E, Roberts SB. The accuracy of stated energy contents of reduced-energy, commercially prepared foods. J Am Diet Assoc. 2010;110(1):116-23. doi: 10.1016/j.jada.2009.10.003.
About Chris Hall
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