Table 2.

Characteristics of included studies. Secondary outcomes: obesity, overweight, and physical activity.

No.	Author, Year, Location	Study Design	Population Description	Exposure	Exposure Assessment	Outcome	Outcome Assessment	Effect Size/Association	Factors Adjusted	Quality Assessment
1	Lovasi et al., 2013, USA [40]	Cross-sectional study	n = 11,562 children, 3–5 years old	Green spaces in neighborhood	Density of trees and park area per km2 using ZIP code	Obesity	Body mass index (BMI) z-score by health care provider	Density of street trees, β = −0.02 CI (−0.08, 0.03); prevalence ratio (PR) = 0.88 (0.79, 0.99) Area covered by parks, β = −0.01 (−0.03–0.01); PR = 0.99 (0.94–1.04)	Sex, race/ethnicity, age, and neighborhood characteristics	10/14
2	Shanahan et al., 2016, Australia [41]	Cross-sectional study	n = 1538, 18–70 years old	Frequency and intensity of exposure to nature	Self-reported by questionnaire/survey using the Nature Relatedness Scale	Physical activity	Number of days exercised for 30 minutes or more per week	Nature experience duration β = 0.19, p < 0.001; nature experience frequency β = 0.16, p < 0.001	Age, gender, income, children in home, neighborhood disadvantage, workday/week, highest qualification, ethnicity, BMI, social cohesion	11/14
3	Prince et al., 2011, Canada [42]	Cross-sectional study	n = 3883, males and female, >18 years old	Green spaces and park areas	Geographic information system, geocode	Obesity Physical activity (PA)	Obesity = BMI measurement PA = Self-reported by questionnaire	Physical activity was lower for men in neighborhoods with a higher green space area, odds ratio (OR) = 0.93, 95% CI (0.87, 0.9). For females, green spaces were protective of being obese or overweight, OR = 0.67 CI (0.54–0.84)	Sex, age, socioeconomic status, social and built environment characteristics	12/14
4	Lovasi et al., 2011, USA [43]	Longitudinal study	n = 428, 2–5 years old, males and females	Green spaces	Street tree density by geographic database	Physical activity	Accelerometer	Land use mix was associated with physical activity (26 more activity counts/minute per standard deviation increase in mixed land use, p = 0.015)	Age, sex, and race/ethnicity, mother (age, born outside of the USA, use of Spanish, employed/student status), household (number of rooms), the total number of hours recorded as awake, the time of year	13/14
5	Hrudey et al., 2015, Netherlands [44]	Cohort	n = 3469, 5–6 years old	Green spaces	Survey with Likert scale of green spaces satisfaction	Obesity and overweight	Self-reported	No significant association was found, after adjusting for variables. β = −0.002, CI 95% (−0.3–0.3)	Maternal pre-pregnancy BMI, maternal smoking during pregnancy (yes, no), duration of exclusive breastfeeding (<3 months, 3–6 months, ≥6 months), and age at introduction of solid foods (<4 months, ≥4 months), Maternal education and maternal BMI	13/14
6	Sanders et al., 2015, Australia [45]	Cohort	n = 4423, 6–13 years old	Green spaces	Proportion of green spaces available in neighborhood by postcode	Obesity	Face-to-face interview, waist circumference (WC), and waist-to-height ratio (WtHR)	Compared to those who have 0% to 5% green spaces at the local level, children with >40% green space tended to have lower WC (β boys, −1.15, 95% CI −2.44, 0.14; β girls, −0.21, 95% CI −1.47, 1.05) and WtHR (β boys, −0.82, 95% CI −1.65, 0.01; β girls, −0.32, 95% CI −1.13, 0.49). No statistically significant results were found	Sex, age, socio economic status	10/14
10	Putrit et al., 2015, USA [46]	Cross-sectional study	n = 9971, >18 years old	Green spaces, parking facilities	Self-reported survey	Obesity/overweight	Self-reported	People who perceived more availability of green spaces showed odds ratio = 0.84, CI (0.72–0.97) for obesity and OR = 1.08, CI (0.98–1.20) for overweight. After adjusting for age, the effect size, for people from 40 to ≤65 OR for obesity = 0.80, CI (0.66–0.96), and >65 years old OR = 0.71, CI (0.54–0.93)	Age, gender, educational level	13/14
11	James et al., 2017, USA [47]	Cohort	n = 23,435 women, 60–87 years old	Green spaces	Normalized difference vegetation Index	Obesity	Self-reported weight and height	No significant association between all variables in the model and BMI 0.01% (−0.36–0.37)	Age, race, smoking status, husband’s education level	10/14
12	Klompmaker et al., 2018, Netherlands [48]	Cross-sectional study	n = 387,195, >19 years old	Green spaces	Distance to the nearest park and normalized difference vegetation index	Obesity Physical activity	Self- reported	No significant association was found, within 100 m of a park compared to the reference category (>1000 m) where 1.04 (95% CI: 0.83–1.25) and 1.02 (95% CI: 0.96– 1.07) for the highly urban and moderate–low urban population, respectively. For the elderly (≥65 years) and non-elderly, these odds ratios were 1.01 (95% CI 0.96–1.07) and 1.02 (95% CI: 0.94–1.08), respectively. Physical activity was higher in people who lived closer to the park entrance, odds ratio = 1.08 (1.03–1.14). For NVDI, greenness increased the OR = 1.14 (1.10–1.17) in the highest quintile compared to that in the lowest.	Age, sex, socioeconomic status, marital status, country of origin, work, household income, level of education, smoking status, alcohol use, indoor physical activity	12/14
13	Petraviciene et al., 2018, Lithuania [49]	Cross-sectional study	n = 1489 mothers and their 4–6-year-old children	Green spaces	Normalized difference vegetation Index	Obesity and overweight	Self-reported by standardized questionnaires	Children who live in areas with less greenness exposure, have higher risk of being obese/overweight OR = 1.72 CI (1.15–2.60), p < 0.05	Family status, maternal age, education, employment status, smoking during pregnancy, secondhand smoking, mother–child relationship, NO2; child´s sex, birth weight, and sedentary behavior	12/14
14	Dadvand et al., 2014, Spain [50]	Cross-sectional study	n = 3178, 9–12 years old	Green spaces	Normalized difference vegetation index, proximity to green space by Urban Atlas Map	Obesity	Self-reported by questionnaire	In relation to 4 buffers of green spaces: 100 m buffer and obesity odds ratio (OR) = 0.32, CI (0.75–0.93), 250 m buffer OR = 0.81, CI (0.71–0.92), 500 m buffer OR = 0.83, CI (0.78–0.98)	Parental education, type of school, sport activity, and having siblings	12/14
15	Coombes et al., 2010, England [51]	Cross-sectional study	n = 6803, >18 years old	Green spaces	Geographic information system, geocoding	Obesity Physical Activity	Self-reported by questionnaire	Respondents who visit green spaces with less frequency showed odds ratio = 0.39, CI (0.33–0.45), p < 0.01 of achieved physical activity guidelines and odds ratio = 1.44, CI (1.25–1.66) of being obese or overweight	Age, sex, socioeconomic status, self-rated health, area-level deprivation	13/14