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Volunteering and Subsequent Health and Well-Being in Older Adults: An Outcome-Wide Longitudinal Approach

Author/s: 
Kim, E.S., Whillans, A.V., Lee, M.T., Chen, Y., VanderWeele, T.J.

ntroduction: Growing evidence documents strong associations between volunteering and favorable health and well-being outcomes. However, epidemiological studies have not evaluated whether changes in volunteering are associated with subsequent health and well-being outcomes.

Methods: Data were from 12,998 participants in the Health and Retirement Study-a large, diverse, prospective, and nationally representative cohort of U.S. adults aged >50 years. Using multiple logistic, linear, and generalized linear regression models, this study evaluated if changes in volunteering (between t0, 2006/2008 and t1, 2010/2012) were associated with 34 indicators of physical health, health behaviors, and psychosocial well-being (in t2, 2014/2016). Models adjusted for sociodemographics, physical health, health behaviors, psychosocial factors, and personality, as well as volunteering and all outcomes in the prebaseline wave (t0, 2006/2008). Results accounted for multiple testing and data were analyzed in 2019.

Results: During the 4-year follow-up period, participants who volunteered ≥100 hours/year (versus 0 hours/year) had a reduced risk of mortality and physical functioning limitations, higher physical activity, and better psychosocial outcomes (higher: positive affect, optimism, and purpose in life; lower: depressive symptoms, hopelessness, loneliness, and infrequent contact with friends). Volunteering was not associated with other physical health outcomes (diabetes, hypertension, stroke, cancer, heart disease, lung disease, arthritis, overweight/obesity, cognitive impairment, and chronic pain), health behaviors (binge drinking, smoking, and sleep problems), or psychosocial outcomes (life satisfaction, mastery, health/financial mastery, depression, negative affect, perceived constraints, and contact with other family/children).

Conclusions: With further research, volunteering is an activity that physicians might suggest to their willing and able patients as a way of simultaneously enhancing health and society.

Keywords 
volunteering volunteer health benefits

Changes in nut consumption influence long-term weight change in US men and women

Author/s: 
X, Li, Y, Guasch-Ferre, M, Willett, WC, Drouin-Chartier, JP, Bhupathiraju, SN, Tobias, DK

Background Nut consumption has increased in the US but little evidence exists on the association between changes in nut consumption and weight change. We aimed to evaluate the association between changes in total consumption of nuts and intakes of different nuts (including peanuts) and long-term weight change, in three independent cohort studies.

Methods and findings Data collected in three prospective, longitudinal cohorts among health professionals in the US were analysed. We included 27 521 men (Health Professionals Follow-up Study, 1986 to 2010), 61 680 women (Nurses’ Health Study, 1986 to 2010), and 55 684 younger women (Nurses’ Health Study II, 1991 to 2011) who were free of chronic disease at baseline in the analyses. We investigated the association between changes in nut consumption over 4-year intervals and concurrent weight change over 20–24 years of follow-up using multivariate linear models with an unstructured correlation matrix to account for within-individual repeated measures. 21 322 individuals attained a body mass index classification of obesity (BMI ≥30 kg/m2) at the end of follow-up.

Average weight gain across the three cohorts was 0.32 kg each year. Increases in nut consumption, per 0.5 servings/day (14 g), was significantly associated with less weight gain per 4-year interval (p<0.01 for all): −0.19 kg (95% CI -0.21 to -0.17) for total consumption of nuts, -0.37 kg (95% CI -0.45 to -0.30) for walnuts, -0.36 kg (95% CI -0.40 to -0.31) for other tree nuts, and -0.15 kg (95% CI -0.19 to -0.11) for peanuts.

Increasing intakes of nuts, walnuts, and other tree nuts by 0.5 servings/day was associated with a lower risk of obesity. The multivariable adjusted RR for total nuts, walnuts, and other tree nuts was 0.97 (95% CI 0.96 to 0.99, p=0.0036), 0.85 (95% CI 0.81 to 0.89, p=0.0002), and 0.89 (95% CI 0.87 to 0.91, p<0.0001), respectively. Increasing nut consumption was also associated with a lower risk of gaining ≥2 kg or ≥5 kg (RR 0.89–0.98, p<0.01 for all).

In substitution analyses, substituting 0.5 servings/day of nuts for red meat, processed meat, French fries, desserts, or potato, chips (crisps) was associated with less weight gain (p<0.05 for all).

Our cohorts were largely composed of Caucasian health professionals with relatively higher socioeconomic status; thus the results may not be generalisable to other populations.

Conclusion Increasing daily consumption of nuts is associated with less long-term weight gain and a lower risk of obesity in adults. Replacing 0.5 servings/day of less healthful foods with nuts may be a simple strategy to help prevent gradual long-term weight gain and obesity.

Keywords 
weight loss diet nuts
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