Nature Relatedness Is Positively Associated With Dietary Diversity and Fruit and Vegetable Intake in an Urban Population

Abstract

Purpose:

Feeling connected to nature, or nature relatedness (NR), can positively impact physical and psychological well-being. However, the relationship between NR and dietary behaviors has not been studied. This research examined the relationship between NR and dietary behaviors, including dietary diversity and fruit and vegetable intake.

Design

Cross-sectional online survey study.

Setting

Philadelphia, Pennsylvania.

Subjects

Adults (n = 317) over 18 years who resided in Philadelphia, PA.

Measures

The NR Scale was used to measure participants’ connection to nature. It includes 21 items across three subscales: self, experience, and perspective (total and subscales range from 1 to 5). Dietary Diversity was assessed using the FAO’s standardized tool (scores range from 0 to 9). To calculate dietary diversity, food groups reported were aggregated into nine food categories: starchy staples; dark green leafy vegetables; vitamin A rich fruits/vegetables; other fruits/vegetables; organ meat; meat/fish; eggs; legumes, nuts/seeds; and milk products. The NCI’s 2-item CUP Fruit and Vegetable Screener was used to estimate daily fruit and vegetable intake (cups/day), and socio-demographic questions were asked.

Analysis

Simple and multivariable regression models were used to examine associations between NR Total and subscale scores with dietary diversity scores and fruit and vegetable intake with NR Total scores and subscale scores. The multivariable models were adjusted for age, race, gender, and income.

Results

People with higher NR Total (P < .001), NR Self (P < .001), NR Perspective (P = .002), and NR Experience (P = .002) were more likely to report greater dietary diversity. Those with higher NR Total (P < .001), NR Self (P < .001), and NR Experience (P < .001) reported greater fruit and vegetable intake. Associations remained significant after adjusting for covariates.

Conclusion

NR was associated with better dietary intake after accounting for socio-demographic indicators. These findings highlight the need for health promotion interventions that enhance NR, such as nature prescription initiatives, urban gardening and greening, and immersion in urban green spaces.

Keywords

nature relatedness nature nutrition

Purpose

Historical and emerging research shows that spending time in nature and green spaces can foster better physical, cognitive and mental health outcomes.^1-3 Further, research suggests that simply feeling connected with the natural world, or nature relatedness (NR), can positively impact well-being.⁴ NR has been associated with better cognitive,⁵ psychological,⁶ and physical health, and greater levels of environmental stewardship.⁷ Despite mounting evidence supporting the positive relationship between NR and health behaviors and outcomes, the relationship between NR and dietary behaviors has not previously been investigated. The aim of this study was to examine the relationship between NR and dietary intake (dietary diversity and fruit and vegetable intake) in a sample of urban-dwelling adults. This work may impact health promotion practices in two ways: (1) nature-based health promotion interventions may increase NR across the lifespan and potentially improve dietary intake; and (2) augmenting dietary interventions with nature-based activities may lead to greater improvements in dietary quality. Bronfenbrenner’s Social Ecological Model provides the theoretical foundation for this research.⁸ In relation to dietary behaviors, the Social Ecological Model posits that an individual’s dietary behaviors are best understood within a framework that considers the interconnected influences of individual-level, interpersonal (family, peers), community (including the environment), and structural factors.^9,10

Methods

Study Design and Sample

In this cross-sectional survey study, participants (n = 317) completed an online survey that included questions about dietary intake, Nature Relatedness (NR), and demographic characteristics. Using TurkPrime Panels, participants were recruited if they were over 18 years of age, could read English, and lived within the City of Philadelphia. A link to an online survey was provided to participants who met study inclusion/exclusion criteria and who provided consent. We used a targeted sampling strategy to mirror the demographic characteristics (gender, income, education and race) of the City of Philadelphia as of the 2010 census (census.gov) to the extent possible. Participants recruited from TurkPrime Panels are automatically screened and matched with studies for which they are eligible. After reviewing the informed consent form, all participants provided consent online as a proxy for written informed consent. Data were collected between May and August of 2017. This study was approved by the Institutional Review Board at Drexel University.

Measures

The Nature Relatedness (NR) Scale was used to measure participants’ connection to nature.⁷ The NR Scale includes 21 items across three subscales: self, experience, and perspective. NR Self is used to assess an individuals’ personal connection to nature. NR Experience is used to assess an individuals’ physical familiarity with nature. NR Perspective is used to describe an individuals’ external world views of nature. Each subscale uses a 5-point Likert scale. Certain items are reverse-scored; scores are averaged and higher scores reflect a stronger connection to nature (range of 1 to 5 for each subscale and total NR). The NR scale has demonstrated acceptable internal validity.⁷

Dietary diversity measures the variety of foods consumed over a reference period and can serve as a proxy for nutrient adequacy. To assess dietary diversity, we used the Food and Agriculture Organization’s Individual Dietary Diversity instrument.¹¹ A list-based recall was used to assess foods and beverages consumed the previous day. To calculate dietary diversity scores, foods reported are aggregated into nine food categories: starchy staples; dark green leafy vegetables; other vitamin A rich fruits and vegetables; other fruits and vegetables; organ meat; meat and fish; eggs; legumes, nuts and seeds; and milk and milk products. Final scores range from 0 to 9.¹¹

The National Cancer Institute’s 2-item CUP Fruit and Vegetable Screener (CUP FVS) was used to estimate daily fruit and vegetable intake.^12,13 This screener includes two questions and provides examples of one-cup equivalents to help participants with portion size estimations; portion size options are close ended. For this research, a continuous variable for fruit and vegetable intake was created using the midpoint of the range each participant selected, and the sum of the midpoints for fruit and vegetables was calculated.

Analysis

We compared means of the NR total scores and the three subscale scores across participant characteristics using independent samples t-tests and one-way ANOVAs. In cases where an omnibus test produced a significant result, post hoc comparisons of the means were performed using Tukey’s Honest Significant Difference test. Bivariate and multivariate regression models were used to examine individual associations between NR scores and dietary behavior. The multivariable models controlled for age, race, gender, and income. Q-Q plots, and plots of the standardized residuals against predicted values were used to detect potential outliers and ascertain assumptions of multivariate normality. All analyses were performed using SAS 9.4 (SAS Institute, Cary, NC).

Results

Study participant (n = 317) characteristics are summarized in Table 1: 51.73% respondents identified as female; 56.46% identified as a member of a racial or ethnic minority group; 53.64% reported an annual income of between $20,800 and $64,999; and fewer than half of all respondents obtained higher than an associate’s degree. The mean dietary diversity score was 4.45 ± 1.99. The average fruit and vegetable intake was 2.73 ± 1.77 cups per day.

Table 1.

Nature relatedness scores across participant (n = 317) characteristics.

		NR Total	NR Self	NR Perspective	NR Experience
Variable	N (%)	Mean (SD)	Mean (SD)	Mean (SD)	Mean (SD)
Age
18–35 years	122 (38.49%)	3.40 (.56)	3.52 (.68)	3.44 (.68)^a**	3.18 (.71)
36–55 years	84 (26.50%)	3.45 (.59)	3.56 (.71)	3.63 (.68)^ab	3.10 (.82)
56+ years	111 (35.01%)	3.53 (.58)	3.65 (.75)	3.72 (.62)^b	3.16 (.87)
Gender
Male/Non-binary¹	153 (48.27%)	3.41 (.49)	3.54 (.66)	3.37 (.62)**	3.26 (.69)**
Female	164 (51.73%)	3.50 (.64)	3.60 (.77)	3.79 (.65)	3.04 (.87)
Race
White, non-Hispanic	138 (43.54%)	3.34 (.55)	3.46 (.67)*	3.47 (.65)**	3.04 (.83)*
Ethnic and racial minorities	179 (56.46%)	3.54 (.59)	3.66 (.74)	3.68 (.68)	3.23 (.76)
Primary language spoken at home
English	259 (81.70%)	3.47 (.58)	3.57 (.73)	3.63 (.67)*	3.14 (.80)
Other languages	58 (18.30%	3.41 (.56)	3.58 (.65)	3.43 (.64)	3.18 (.78)
Income
Less than $20,800	75 (24.84%)	3.38 (.59)	3.46 (.67)	3.50 (.70)	3.11 (.80)
$20,800 - $64,999	162 (53.64%)	3.50 (.58)	3.63 (.74)	3.64 (.64)	3.18 (.78)
$65,000 or more	65 (21.52%)	3.48 (.55)	3.65 (.67)	3.55 (.69)	3.17 (.88)
Educational
Associate’s degree or below/other	170 (53.63%)	3.39 (.57)	3.49 (.71)*	3.53 (.64)	3.11 (.81)
Bachelor’s degree or above	147 (46.37%)	3.53 (.58)	3.67 (.71)	3.66 (.70)	3.20 (.78)
Body mass index (kg/m²)
Less than 30	217 (69.11%)	3.49 (.59)	3.62 (.74)	3.57 (.69)	3.23 (.77)**
30 or more	97 (30.89%)	3.35 (.53)	3.44 (.64)	3.61 (.62)	2.93 (.80)
Recommended physical activity
Yes	151 (47.63%)	3.55 (.57)^**	3.71 (.70)^**	3.53 (.67)	3.35 (.75)^**
No	166 (52.37%)	3.38 (.57)	3.45 (.71)	3.65 (.67)	2.96 (.79)

Note. Nature relatedness (NR) Total scores and subscales range from 1 to 5.

¹There was 1 non-binary participant.

^*P < .05; ^**P < .01; ^***P < .001.

^abMeans sharing the same subscript are not significantly different from each other (Tukey’s HSD, P < .05).

NR scores varied substantially across participant characteristics (Table 1). Simple linear regression results showed people with higher NR Total, NR Self, and NR Experience reported greater fruit and vegetable intake; and those with higher NR Total, NR Self, NR Perspective, and NR Experience reported greater dietary diversity (Table 2). These associations remained significant at the .05 level after adjusting for covariates (gender, age, race, and income).

Table 2.

Relationships between nature relatedness and dietary intake.

Nature relatedness (NR)	Beta coefficient	Standard error	t statistic
Fruit and Vegetable Intake
Crude model
NR total score	.79^***	.17	4.74
NR self	.66^***	.13	4.96
NR perspective	.26	.15	1.77
NR experience	.52^***	.12	4.29
Adjusted model
NR total score	.69^***	.17	4.09
NR self	.58^***	.14	4.27
NR perspective	.15	.16	.90
NR experience	.53^***	.12	4.40
Dietary diversity
Crude model
NR total score	.85^***	.19	4.51
NR self	.65^***	.15	4.27
NR perspective	.52^**	.16	3.17
NR experience	.43^**	.14	3.10
Adjusted model
NR total score	.63^**	.20	3.23
NR self	.48^**	.16	3.02
NR perspective	.35^*	.18	1.91
NR experience	.39^**	.14	2.76

Note. Beta coefficients are unstandardized. Covariates in adjusted models: gender, age, race, education, and income.

^*P<.05; ^**P<.01; ^***P<.001.

Discussion

Summary

These results suggest that higher NR is associated with a more diverse dietary intake and higher fruit and vegetable consumption among urban-dwelling individuals, after accounting for socio-demographic indicators. Therefore, these findings augment the current evidence for leveraging nature-based experiences to improve healthful dietary intake.

Limitations

Limitations of this research include the cross-sectional design, self-report measures, and limited generalizability to adults in an urban, northeast city in the US. The findings of studies that use self-report methodology can be subject to social desirability bias. In studies that assess dietary intake, this can lead to an over-estimated intake of healthful foods, such as fruits and vegetables, and an under-estimated intake of foods high in energy density, saturated fat and sugar. TurkPrime Panels demographic screening tools allowed researchers to obtain a sample of Philadelphia residents mirroring Philadelphia’s broader demography, and in doing so (theoretically) generated a representative sample.¹⁴ However, this targeted sampling also limits the generalizability of these findings and the results may not be applicable to other urban or rural areas of the US. While open and list-based recalls are in moderate agreement, their predictive performance for dietary diversity is satisfactory; over-reporting of certain food groups is possible.¹⁵ When compared to multiple 24-hour recalls, the CUP FVS has yielded comparable values for vegetable intake but over-estimated fruit intake.¹³ Suggesting relatively strong reliability, intraclass correlation coefficients for test-retest reliability have ranged from .62 to .67.¹³

Significance

These findings highlight the potential for leveraging nature-based experiences to improve healthful dietary intake. Such interventions may include incorporating green spaces/urban greening into city planning, integrating nature and park prescription programs into healthcare practices, and promoting nature-based experiences in the classroom settings, among many others. Nature-based experiences during childhood have been associated with positive child health outcomes and may also lead to increases in NR.¹⁶ Therefore, effective approaches for teaching parents how to foster NR in their children, involving comfort and enjoyment of natural settings, is an exciting area for future study.

Interventions within urban places, such as Philadelphia, will require decision-makers to grapple with the interconnectedness of food apartheid, inequities in natural and built environments and green space availability, and uncertain physical safety. Historically, interventions to ameliorate urban “blight” have led to gentrification, displacing communities and residents.^17,18 While improving dietary intake through nature-based interventions may be valuable, it is also complex and coordination must include community members and stakeholders. Future research should elucidate the ways by which communities experience and value nature, and how the intersections of environment, culture, race, gender, social cohesion, and socioeconomic position influence community identity relative to NR and dietary intake.

“SO WHAT”

What is already known?

NR has been associated with better cognitive and psychological health, and higher levels of environmental stewardship.

What does this article add?

People with higher NR were more likely to report healthful dietary intake, including greater dietary diversity and higher fruit and vegetable consumption.

What are the implications for health promotion practice or research?

Nature-based health promotion interventions, such as urban greening, promotion of biophilic design, and park and nature prescription programs may increase NR in individuals, thereby potentially leading to improvements in dietary intake.

Footnotes

Author Contribution

Conceptualization: BJM, DW, EVE, FM, MCC. Data collection: BJM, MCC, FM, DW. Data analysis: JM, JG. Data interpretation: BJM, JM, JG, DW, DS. Manuscript preparation: BJM, DS. Manuscript review and editing: BJM, DW, EVE, FM, JG, JM, DS. Funding acquisition: EVE, BJM, DW, FM.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Drexel Watershed Consortium Watershed Research Seed Funding.

Ethics Statement

This research was conducted according to the World Medical Association Declaration of Helsinki. Drexel University’s. Institutional Review Board reviewed and approved this study (Protocol # 1612005052).

ORCID iDs

Brandy-Joe Milliron

Dane Ward

Janeway Granche

Janell Mensinger

References

Shanahan

Bush

Gaston

, et al. Health benefits from nature experiences depend on dose. Sci Rep. 2016;6:28551. doi:10.1038/srep28551

Berman

Kross

Krpan

, et al. Interacting with nature improves cognition and affect for individuals with depression. J Affect Disord. 2012;140:300-305. doi:10.1016/j.jad.2012.03.012

Roe

Thompson

Aspinall

, et al. Greenspace and stress: Evidence from cortisol measures in deprived urban communities. Int J Environ Res. Public Health. 2013;10(9):4086-4103. doi:10.3390/ijerph10094086

Capaldi

Dopko

Zelenski

. The relationship between nature connectedness and happiness: a meta-analysis. Front Psychol. 2014;5:976. doi:10.3389/fpsyg.2014.00976

Berman

Jonides

Kaplan

. The cognitive benefits of interacting with nature. Psychol Sci. 2008;19(12):1207-1212. doi:10.1111/j.1467-9280.2008.02225.x

Martyn

Brymer

. The relationship between nature relatedness and anxiety. J Health Psychol. 2016;21(7):1436-1445. doi:10.1177/1359105314555169

Nisbet

Zelenski

Murphy

. The nature relatedness scale: Linking individuals' connection with nature to environmental concern and behavior. Environ Behav. 2008;41(5):715-740. doi:10.1177/0013916508318748

Bronfenbrenner

. Ecological systems theory. In: Vasta

, ed.Annals of Child Development, 6. Greenwich, CT: JAI Press; 1989:187-249.

Sallis

Owen

Fisher

. Ecological models of health behavior. In: Glanz

Rimer

Viswanath

, eds. Health Behavior and Health Education: Theory, Research and Practice. San Francisco, CA: Jossey-Bass; 2008:465-485.

10.

Trapp

Hickling

Christian

, et al. Individual, social, and environmental correlates of healthy and unhealthy eating. Health Educ Behav. 2015;42(6):759-768. doi:10.1177/1090198115578750

11.

Food and Agricultural Organization . Guidelines for Measuring Household and Individual Dietary Diversity. Rome, Italy: Food and Agricultural Organization; 2013. Available at: http://www.fao.org/publications/card/en/c/5aacbe39-068f-513b-b17d-1d92959654ea/

12.

Erinosho

Pinard

Nebeling

, et al. Development and implementation of the National Cancer Institute’s Food Attitudes and Behaviors Survey to assess correlates of fruit and vegetable intake in adults. PLoS One. 2015;10(2):e0115017. February 23. doi:10.1371/journal.pone.0115017

13.

Yaroch

Tooze

Thompson

, et al. Evaluation of three short dietary instruments to assess fruit and vegetable intake: The National Cancer Institute’s Food Attitudes and Behaviors (FAB) Survey. J Acad Nutr Diet. 2012;112(10):1570-1577. doi:10.1016/j.jand.2012.06.002

14.

Litman

Robinson

Abberbock

. TurkPrime.com: A versatile crowdsourcing data acquisition platform for the behavioral sciences. Behav Res. 2017;49:433-442. doi:10.3758/s13428-016-0727-z

15.

Hanley-Cook

Tung

JYA

Sattamini

, et al. Minimum dietary diversity for women of reproductive age (MDD-W) data collection: Validity of the list-based and open recall methods as compared to weighed food record. Nutrients. 2020;12(7):2039. doi:10.3390/nu12072039

16.

Mygind

Kjeldsted

Hartmeyer

Mygind

Bølling

Bentsen

. Mental, physical and social health benefits of immersive nature-experience for children and adolescents: a systematic review and quality assessment of the evidence. Health Place. 2019;58:102136-102215. doi:10.1016/j.healthplace.2019.05.014

17.

Pearsall

Eller

. Locating the green space paradox: A study of gentrification and public green space accessibility in Philadelphia, Pennsylvania. Landsc Urban Plan. 2020;195:103708. doi:10.1016/j.landurbplan.2019.103708

18.

Wolch

Byrne

Newell

. Urban green space, public health, and environmental justice: The challenge of making cities ‘just green enough. Landsc Urban Plan. 2014;125:234-244. doi:10.1016/j.landurbplan.2014.01.017