Effects of Long-Term Walnut Supplementation on Body Weight in Free-Living Elderly: Results of a Randomized Controlled Trial

Nutrients. 2018 Sep 18;10(9):1317. doi: 10.3390/nu10091317.

Abstract

Objective: To assess the effects of chronic walnut consumption on body weight and adiposity in elderly individuals. Methods: The Walnuts and Healthy Aging study is a dual-center (Barcelona, Spain and Loma Linda University (LLU)), 2-year randomized parallel trial. This report concerns only the LLU cohort. Healthy elders (mean age 69 year, 67% women) were randomly assigned to walnut (n = 183) or control diets (n = 173). Subjects in the walnut group received packaged walnuts (28⁻56 g/day), equivalent to ≈15% of daily energy requirements, to incorporate into their habitual diet, while those in the control group abstained from walnuts. Adiposity was measured periodically, and data were adjusted for in-trial changes in self-reported physical activity. Results: After 2 years, body weight significantly decreased (p = 0.031), while body fat significantly increased (p = 0.0001). However, no significant differences were observed between the control and walnut groups regarding body weight (-0.6 kg and -0.4 kg, respectively, p = 0.67) or body fat (+0.9% and +1.3%, respectively, p = 0.53). Lean body mass, waist circumference, and waist-to-hip ratio remained essentially unchanged. Sensitivity analyses were consistent with the findings of primary analysis. Conclusion: Our findings indicate that walnuts can be incorporated into the daily diet of healthy elders without concern for adverse effects on body weight or body composition.

Keywords: adiposity; body weight; elderly; energy; nuts; obesity; walnuts.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Adiposity*
  • Age Factors
  • Aged
  • Body Weight*
  • California
  • Energy Intake
  • Female
  • Healthy Aging*
  • Humans
  • Independent Living*
  • Juglans* / adverse effects
  • Male
  • Nutritional Status
  • Nuts* / adverse effects
  • Recommended Dietary Allowances
  • Spain
  • Time Factors
  • Treatment Outcome