Body Mass Index

Body Mass Index

The numerous findings showing that peanuts help you manage your weight all fall in line with population studies showing that people who eat peanut and peanut butter tend to have a lower Body Mass Index (BMI).

  • The Deep South Network study showed that overweight and obese women who ate peanuts and nuts had  lower BMI values at the end of a two-year weight loss intervention than those who didn’t.
  • After the 5 year EPIC-PANACEA study, it was found that a higher intake of nuts, including peanuts, resulted in a lower risk for being overweight or obese.
  • The Adventist Health Study showed that those who ate more peanuts and nuts were less obese.
  • The Nurses’ Health Study showed that women who ate more peanuts and nuts were leaner.
  • The Continuing Survey of Food Intakes by Individuals showed that children and adults who reported eating peanuts and nuts had lower BMIs.

When researchers at Purdue University conducted the first human study to explain this evidence, they gave participants peanuts as a substitution for other calories in the diet or added them to the diet as additional calories. The researchers discovered that people naturally decreased what they ate at other times of the day when eating peanuts. This may be why there is little or no change in body weight with peanut consumption.

The fact that eating peanuts reduces hunger may contribute to this occurrence. In addition to containing protein and fiber that promote fullness, peanuts have a low glycemic index. This means that your blood sugar may not shoot up and dip down, which can cause an increased appetite.

Research also suggests peanuts may not be fully digested by the body, so some of the peanut may pass through your system without being absorbed.

In combination with these other factors, research shows that peanuts increase energy expenditure. One study in which participants ate 3 ounces of peanuts daily for 19 weeks showed an 11% increase in resting energy expenditure. This was confirmed in a second study and was also found to be true among obese individuals.

Although the research is still emerging as to why peanut eaters tend to weigh less and have more control over their weight in general, different mechanisms are probably contributing to this effect. The great thing is, we don’t have to wait to figure it out; we can still enjoy the benefits of eating peanuts, knowing that, regardless of the cause, they’re helping us lose weight and keep it off.

Last reviewed: February 2019


Freisling H, Noh H, Slimani N, Chajès V, May AM, Peeters PH, Weiderpass E, Cross AJ, Skeie G, Jenab M, Mancini FR, Boutron-Ruault MC, Fagherazzi G, Katzke VA, Kühn T, Steffen A, Boeing H, Tjønneland A, Kyrø C, Hansen CP, Overvad K, Duell EJ, Redondo-Sánchez D, Amiano P, Navarro C, Barricarte A, Perez-Cornago A, Tsilidis KK, Aune D, Ward H, Trichopoulou A, Naska A, Orfanos P, Masala G, Agnoli C, Berrino F, Tumino R, Sacerdote C, Mattiello A, Bueno-de-Mesquita HB, Ericson U, Sonestedt E, Winkvist A, Braaten T, Romieu I, Sabaté J. Nut intake and 5-year changes in body weight and obesity risk in adults: results from the EPIC-PANACEA study. Eur J Nutr. 2018 Oct;57(7):2399-2408. doi: 10.1007/s00394-017-1513-0. Epub 2017 Jul 21. PubMed PMID: 28733927.

Sterling SR, Bertrand B, Judd S, Carson TL, Chandler-Laney P, Baskin ML. Longitudinal Analysis of Nut-Inclusive Diets and Body Mass Index Among Overweight and Obese African American Women Living in Rural Alabama and Mississippi, 2011-2013. Prev Chronic Dis. 2017 Sep 21;14:E82. doi: 10.5888/pcd14.160595. PubMed PMID: 28934081; PubMed Central PMCID: PMC5609494.

Sabaté J. Nut consumption and change in weight: the weight of the evidence. Br J Nutr. 2007 Sep;98(3):456-7. Epub 2007 Jul 20. Review. PubMed PMID: 17640447.

Griel AE, Eissenstat B, Juturu V, Hsieh G, Kris-Etherton PM. Improved diet quality with peanut consumption. J Am Coll Nutr. 2004 Dec;23(6):660-8. PubMed PMID: 15637214.

Alper CM, Mattes RD. Effects of chronic peanut consumption on energy balance and hedonics. Int J Obes Relat Metab Disord. 2002 Aug;26(8):1129-37. PubMed PMID: 12119580.

Hu FB, Stampfer MJ, Manson JE, Rimm EB, Colditz GA, Rosner BA, Speizer FE, Hennekens CH, Willett WC. Frequent nut consumption and risk of coronary heart disease in women: prospective cohort study. BMJ. 1998 Nov 14;317(7169):1341-5. PubMed PMID: 9812929; PubMed Central PMCID: PMC28714.

Fraser GE, Sabaté J, Beeson WL, Strahan TM. A possible protective effect of nut consumption on risk of coronary heart disease. The Adventist Health Study. Arch Intern Med. 1992 Jul;152(7):1416-24. PubMed PMID: 1627021.