Traditionally, community-supported agriculture (CSA) is a system wherein individuals in a community pledge to support a local farm financially and, for some groups, by helping out on the farm; these shareholders then receive shares of the farm’s goods during the growing season and also share in the risks of crop failure.^1,2 The traditional, or membership/share, CSA model can be started by farmers or community members, typically has membership periods of six or 12 months, and involves only a single farm.² 

Another type of CSA is the subscription model, wherein individuals purchase subscriptions to receive farm shares, with the frequency of shares (eg, weekly, monthly, seasonally) dependent upon each individual farm. This model is more customer-oriented than the membership/share model, as shareholders typically do not share in the risks of farming; farmers may purchase goods from other farms to supplement subscription shares in the case of crop failure. This model is often more accessible, particularly for urban residents. Subscription-based CSAs are initiated by farmers, and farmers may collaborate to create shares with goods from multiple farms.² 

The content of shares varies depending upon the farm(s) involved. Examples of goods provided in shares include fruits and/or vegetables, meat, dairy, eggs, bread, grains, seeds, beans, honey, and flowers.²

CSA and Nutrition

Studies have shown that participating in a CSA can lead to increased fruit and vegetable consumption.^3–9 A randomized controlled trial found that individuals who received a subsidized CSA share had a significantly higher mean Healthy Eating Index (HEI) score during the growing season, compared to controls who received a brochure on healthy eating and financial compensation for research visit attendance that was equal to the CSA subsidy. Further analysis of HEI items indicated that the intervention group had significantly higher consumption of total vegetables, total fruits, and whole fruits. Additionally, food insecurity prevalence fell from 32 percent at baseline to 11 percent during the intervention for shareholders (prevalence was 42% in control group).³ 

One survey of new and returning CSA shareholders found that mean weekly vegetable intake rose from 27.1 to 31.5 servings per week in the pre- to post-CSA periods (defined as before first CSA share was received and immediately after the CSA season, respectively). Three months after the end of the CSA season, mean weekly vegetable consumption was similar to pre-CSA levels, at 27.4 servings per week, thus demonstrating the beneficial effect that receiving weekly shares had on participants’ vegetable intake. Over half of all participants stated that they tried at least one new vegetable during the CSA season, and among these individuals, a mean of 3.7 new vegetables were tried. Additionally, 52 percent of participants gained a liking for vegetables that they had not liked before partaking in the CSA.⁴

In a 2017 study, adults and children in low-income households who participated in a cost-offset CSA program had significantly greater median fruit and vegetable intake than the United States (US) median intake. Over 80 percent of adults and children met the Dietary Guidelines for Americans recommended vegetable intake. Data from a winter survey, completed by 23 of 41 households, showed that median fruit and vegetable intake was similar during and after the CSA season.⁵ Another study found that among low-income households, those who were provided with a CSA subscription (n=21) significantly increased their total inventories of fruits and vegetables and of vegetables alone from baseline (May 2010) to follow-up (August 2010); control participants (n=23) did not demonstrate a significant increase in either measure. The intervention group increased their average fruit and vegetable intake from 16.0 to 18.7 servings per week. There was no significant difference in fruit and vegetable consumption between groups, but the intervention group did have a numerically higher intake at follow-up (18.7 vs. 16.4 servings/week).⁶

A study from the University of Kentucky assessed the impact of an employer-sponsored CSA voucher program on food lifestyle behaviors among employees with no prior experience with CSA programs.⁷ Average daily servings of fruits and vegetables rose from 4.01 pre-CSA (April 2015) to 4.52 post-CSA (October 2015). Further analyses compared controls, intervention participants who reported “extremely poor,” “poor,” or “average” health (lower health [LH] group), and intervention participants who reported “good” or “excellent” health (higher health [HH] group). The LH group showed a significantly greater fruit and vegetable consumption from pre- to post-CSA, with a mean increase of 0.73 servings per day, compared to controls, who experienced a mean decrease of 0.79 servings per day.⁷ In a continuation of this study,⁸ which included data from 2015 to 2018, researchers found that daily fruit and vegetable intake rose slightly among shareholder. Subgroup analysis showed that the LH group reported a significant increase in fruit and vegetable consumption of 0.6 servings per day from pre- to post-CSA, whereas the HH group had a nonsignificant increase of 0.1 servings per day. 

These studies also measured other food-related behaviors, such as processed food intake, eating food away from home, and interest in nutrition.^7,8 In the initial study, shareholders reported significant decreases in monthly consumption of processed snacks and processed meals after participating in the CSA program. The LH and HH groups both reported significantly lower mean intake of processed snacks and meals, compared to controls. From pre- to post-CSA, shareholders also reported reduced weekly expenditure at restaurants, greater cooking expertise, increased purchase of locally produced foods (excluding the CSA), and greater awareness of food sources. Data on between-group differences demonstrated that the LH group saw the most significant behavioral changes compared to the control group.⁷ Similar to the first study, the second study showed that shareholders reported significantly monthly lower consumption of processed snacks and meals following the CSA intervention; this difference was also significant for the LH and HH groups separately. Shareholders also reported that they read nutrition labels more, bought more locally produced food, bought more food directly from farmers, prepared dinner at home more, and ate at restaurants less. Shareholders also indicated that they more often preserved food by freezing and canning, and these behaviors remained significant in subgroup analysis of the LH and HH groups.⁸

CSA and Health

Some evidence suggests that CSA participation might help improve health outcomes.^7–9 In the University of Kentucky studies, CSA shareholders reported better digestive health and improved self-evaluated health.^7,8 A microsimulation study published in the American Journal of Public Health evaluated the potential impact of a subsidized CSA intervention on health outcomes in low-income adults with a body mass index (BMI) greater than 25kg/m².⁹ The simulated CSA intervention was compared to a simulated intervention wherein individuals received an amount of cash equivalent to the subsidy along with guidance on healthy eating, and there were no restrictions on how to use the money. Both interventions were found to be cost-effective, though the CSA intervention resulted in a greater reduction from baseline in disability-adjusted life years over a life-course horizon than the cash intervention (22,304 per 10,000 people vs. 23,463 per 10,000 people; baseline: 24,797 per 10 000 people). The CSA intervention showed slightly more beneficial reductions in estimated median 10-year and life-course risks of atherosclerotic cardiovascular disease events, incident diabetes, diabetic neuropathy, and diabetic retinopathy, as well as estimated median 10-year all-cause mortality risk, from baseline, compared to the cash intervention group.⁹

Bottom Line

Participating in a CSA program can be a good way to support local agriculture and increase your fruit and vegetable intake, in addition to introducing you to new produce. It might even benefit your health, although more research in this area is needed before any conclusions can be made. If you’re interested in finding a CSA near you, you can visit https://www.localharvest.org

Sources

1. DeMuth S. Community supported agriculture (CSA): an annotated bibliography and resource guide. US Department of Agriculture, Alternative Farming Systems Information Center. 1993. Accessed 4 Feb 2024. https://search.nal.usda.gov/discovery/delivery/01NAL_INST:MAIN/12285290950007426
2. Unit 3: Community supported agriculture. In: Perez J, Brown M, Miles A, eds. Teaching Direct Marketing & Small Farm Viability, 2nd edition. Center for Agroecology & Sustainable Food Systems, University of California, Santa Cruz. 2015; 43–143.
3. Berkowitz SA, O’Neill J, Sayer E, et al. Health center-based community-supported agriculture: an RCT. Am J Prev Med. 2019;57(6 Suppl 1):S55–S64. 
4. Wilkins JL, Farrell TJ, Rangarajan A. Linking vegetable preferences, health and local food systems through community-supported agriculture. Public Health Nutr. 2015;18(13):2392–2401. 
5. Hanson KL, Kolodinsky J, Wang W, et al. Adults and children in low-income households that participate in cost-offset community supported agriculture have high fruit and vegetable consumption. Nutrients. 2017;9(7):726.
6. Quandt SA, Dupuis J, Fish C, D’Agostino RB Jr. Feasibility of using a community-supported agriculture program to improve fruit and vegetable inventories and consumption in an underresourced urban community. Prev Chronic Dis. 2013;10:E136. 
7. Rossi JJ, Woods TA, Allen JE IV. Impacts of a community supported agriculture (CSA) voucher program on food lifestyle behaviors: evidence from an employer-sponsored pilot program. Sustainability. 2017;9(9):1543.
8. Rossi J, Woods T. Incentivizing wellness through community supported agriculture: Reflections on shareholder impacts of an employer-based CSA voucher program. J Agric Food Syst Community Dev. 2021;11(1):27–44.
9. Basu S, O’Neill J, Sayer E, et al. Population health impact and cost-effectiveness of community-supported agriculture among low-income US adults: a microsimulation analysis. Am J Public Health. 2020;110(1):119–126.