Bad Rap

April 4, 2021


We’re eating more tree nuts than ever…and they may have FEWER calories than we thought.


  • BACKGROUND: The USDA and most food manufacturers rely on a century-old formula (1 gram of protein = 4 calories; 1 gram of fat = 9 calories) to calculate a given food’s calorie content.
  • RECENT: That formula might not apply when it comes to certain tree nuts because they aren’t broken down (digested) like other foods, and therefore our bodies don’t absorb as much energy (calories).

About The Studies

  • 2011: USDA researchers began studying how almonds, walnuts, & pistachios are digested in human “waste.”
  • Using those samples, researchers calculated how much fat, protein, carbohydrates, & calories were absorbed by the participant.
  • Results: Nuts had fewer *digestible* calories vs. calorie counts on labels: almonds (-32%), walnuts (-21%) & pistachios (-5%).


“If they’re not digested, then maybe the calorie content is not correct.”

Dr. David Baer, one of the USDA researchers involved in the studies.

Also Worth Noting

  • Researchers found the more the nut is cooked (or processed), the more calories digested. Example: Almond butter has more calories than roasted almonds, but roasted almonds have more calories than raw almonds.
  • U.S. Department of Agriculture’s Agricultural Research Service unit conducted the studies. Nut producers and organizations contributed funding.


“We can create synthetic DNA and clone animals but we still know incredibly little about the stuff that keeps us alive.”

Prof. Tim Spector, Kings College in London, on nutrition science: "No other field of science or medicine sees such a lack of rigorous studies." Food manufacturers create their own nutrition labels. Research has raised questions about accuracy of labels & whether counts can be "one-size-fits-all."

Kind Bars recently announced it’s cutting the calorie counts of its nut bars by 10-30 calories per bar because of the new research. Are chocolate-covered nuts next? DON’T COUNT ON IT! Mars, which owns a share of Kind, isn’t planning on lowering its calorie counts for M&M’s with almonds.

How many calories in almonds? Turns out, that’s a tough nut to crack.

by Jenna Lee,