CSAs: Health Impacts and Barriers to Use


Hoop House and Cherry Tomatoes

By Alyson McAdams, University of Michigan Dietetics Intern

When I started at the farm, I had heard the term “CSA” before, but didn’t know what the letters stood for. In the first couple days, I finally found out – “community supported agriculture”. In a CSA, the consumer pays the farmer up front for a ‘share’ of the produce, and the farmers provide fruits and vegetables each week through the season. The community supporting farmers, farmers providing food to the community–all great things I could get behind.


CSA preparation and packing

The farm runs their own collaborative CSA with help from some local farmers and prepares weekly shares for their participants. They run a CSA in partnership with Parkridge Community Center in Ypsilanti that is fully subsidized CSAs for folks who otherwise may be unable to afford it. Each week I watched beautiful fresh fruits and veggies being packed into bags and distributed, while doing some recipe demos and sampling. All of this sounds so beautiful in theory — so I wanted to see the research to back it up. What were the individual health and wellness  impacts of participating in a CSA? If it was such a great program, what was getting in people’s way of participation?

What is preventing Americans from eating enough produce? The answer is long, complex, and ever-evolving. Income influences what and how people eat, and low-income consumers often have more barriers to fresh produce. However, most CSA members across the country are in middle- to high-income households, and the cost of CSAs prevents those with a lower income from participating (1), especially when they don’t know what or how much they will get from the CSA each week (2). However, cost-offset CSAs have been shown to be more accessible (1). Cost-offset CSAs are those which have had the price reduced in some way, either partially or fully. Reducing the price of CSAs, or accepting benefits such as SNAP, helps to remove the barriers to healthy food for many people.

What are the health benefits of getting a CSA? Eating a diet rich in fruits and veggies is good for our bodies and leads to better health outcomes over time (1). Eating vegetables can help lower our risk of chronic diseases while also maintaining a healthy weight (3).However, the average American’s fruit and vegetable intake is less than half of what is recommended by the Dietary Guidelines for Americans(1), and a third of the vegetables we eat are potatoes and tomatoes (3). This means we are missing opportunities to eat more vegetables, and we aren’t getting enough colors, vitamins, and minerals. A review done at Montana State University found that among CSA members, the amount AND variety of fruits and veggies eaten increases and more people are meeting the Dietary Guidelines standard, across socioeconomic status (4).


Harvesting Greens

In studies comparing CSA and non-CSA members, CSA members ate more dark greens and yellow fruits and vegetables, and were taking in more fiber and Vitamin A (4). Fruits and vegetables contain many amazing vitamins and minerals, and the more variety we eat, the more nutrients we get. Many of the foods given out in CSAs have high levels of phytochemicals and antioxidants–which can be protective against cancers and inflammation. Increased fruit and vegetable intake over time is linked to lower risk of chronic disease, specifically heart disease (4). Through its amount and variety of produce, the studies found that a CSA is positive for individual health. Furthermore, in studies focusing on low-income CSAs, less than eight percent of the sample said that they had difficulty physically accessing fruits and vegetables, a marked difference from the control (1).


Families at Farm to Table Camp

Participation in a CSA can also positively impact family life and health habits. Studies have shown that while participating in a CSA, families increasingly cook at home, cook as a family, and have family meals. Family meals increase the health and well-being of adolescents, while cooking together helps to teach children skills about food and cooking (4). Fruits and vegetables were more often served at snacks and meals, presumably replacing less healthy options (5). Eating at home means that families eat out less; Restaurant eating is associated with bigger portions and more calories, so switching to eating at home and preparing meals together is a great improvement (5).

Overall, CSAs appear to be linked to improved health, community, and well-being. More work needs to be done to conduct more research and make CSAs accessible to all people of all backgrounds, since the benefits apply to all. CSAs are an effective way for people to connect with their food, connect with a farm, and connect with each other.


(1) Hanson, K. L., Kolodinsky, J., Wang, W., Morgan, E. H., Pitts, S. B. J., Ammerman, A. S., … & Seguin, R. A. (2017). Adults and Children in Low-Income Households That Participate in Cost-Offset Community Supported Agriculture Have High Fruit and Vegetable Consumption. Nutrients, 9(7), 726.
(2) Cotter, E. W., Teixeira, C., Bontrager, A., Horton, K., & Soriano, D. (2017). Low-income adults’ perceptions of farmers’ markets and community-supported agriculture programmes. Public health nutrition, 1.
(3) Wilkins, J. L., Farrell, T. J., & Rangarajan, A. (2015). Linking vegetable preferences, health and local food systems through community-supported agriculture. Public health nutrition, 18(13), 2392-2401.
(4) Harmon, A. H. (2014). Community supported agriculture: A conceptual model of health implications. Austin J Nutri Food Sci, 2(4), 1024.
(5) Vasquez, A., Sherwood, N. E., Larson, N., & Story, M. (2016). A novel dietary improvement strategy: Examining the potential impact of community-supported agriculture membership. Public health nutrition, 19(14), 2618-2628.



Why you should not store tomatoes in the refrigerator?


By Maymona Al Hinai, University of Michigan Dietetics Intern

During my dietetic internship rotation in The Farm at St. Joe’s, I learned a lot of amazing things about farming, how to deal with plants, preparing health recipes, and CSA (community supported agriculture). I also try new things for first time such as kale, collard greens, basil and farmer market! One of the interesting things that I come across while I am here was to keep harvested tomatoes outside and not in the cooler. Coming from a very hot county like Oman, I always stored tomatoes in the refrigerator to extend their life and keep the molds away, I only keep them outside if it is green or unripe.

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To fill my research curiosity, I decided to make a very simple experiment to test whether the tomatoes left outside the refrigerator has any differences than the tomatoes in the refrigerator. I pick up some red and ripe cherry tomatoes from the farm and divided them to two groups (group A and group B, 7 cherry tomatoes in each). I stored group A on the counter at room temperature around 77 F and stored group B in the refrigerator at 41 F for 5 days. After I take off the tomatoes from the fridge and let their temperature down to room temperature, I blinded the groups and let my friends in the farm taste the tomatoes and notice any differences. The result was unclear as some found tomatoes in the fridge sweeter, softer, and riper where others found that these are the features of tomatoes left in the counter. Because the results were mixed, I try the experiment in different verity of tomatoes, the slicing tomatoes. For the slicing tomatoes, the difference was more clear and obvious as the tomatoes stored on the counter was more flavored and softer compare to tomatoes stored at lower temperature. This means that low temperature can affect the tomatoes and induce certain changes.

Well, unlike me maybe you already know that you should not store tomatoes in the refrigerator and keep it on the counter, but do you know why? Or what is the scientific evidence of this practice? Here are some of the research conducted to study this issue.

A study in New Zealand investigated the nutritional implication of storing harvested tomatoes in three different temperature at 45 F in a refrigerator, and at 59 and 77 F in temperature controlled incubators for 10 days (1). The results showed that tomatoes stored at 59 and 77 become redder than tomatoes stored at 45. This is because lycopene accumulation – a compound responsible for the red color of tomatoes and good for heart health too- was 2-fold more in tomatoes stored at higher temperature compare to tomatoes stored in the refrigerator. Moreover, the tomatoes acidity was higher in tomatoes stored at 59 and 77 F than at 45 F which may be due the decrease in acid production at low temperature.

Another study published in the Journal of Food Science found that the tomatoes ripe smell, flavor, and sweetness was significantly lowered at temperature below 55 F compare to 68 F, an effect caused by decline in the production of specific compounds at low temperature (2). In a more recent investigation, researchers found that storing tomatoes at low temperature induce a chilling injury that decrease their smells (3). Chilling injury is  physiological changes caused by improper storage temperatures of postharvest fruit and vegetables (4). Chilling injury makes tomatoes welt, change their texture, fail to fully ripe, loss flavor and smell, and decay (4).

So given what was discussed, what is the ideal temperature to store tomatoes? Well, according to the FAO, ripe tomatoes should be stored at 55-60 F (13-15 °C) whereas mature-green tomatoes can be stored at 65-72 F (18-22 °C). Storing tomatoes at proper temperature is important to preserve the nutrients, flavor, and quality of the tomatoes.

Now you know why they always say keep the tomatoes out of the fridge!


The Farm at St. Joe’s has a farmer market in the main entrance of St. Joe’s hospital every Wednesday. Stop by on Wednesday, to pick up a super delicious cherry tomatoes with other good veggies:)

Also, Check this link for other proper fruit and vegetable storage temperature: http://www.fao.org/WAIRdocs/x5403e/x5403e09.htm.


  1. Toor RK, Savage GP. Changes in major antioxidant components of tomatoes during post-harvest storage. Food Chem. 2006;99:724–7.
  2. Maul F, Sargent S.A., Sims C.A., Baldwin E.A., Balaban M.O. HDJ. Tomato Flavor and Aroma Quality as Affected by Storage Temperature. J Food Sci. 2000;65:1228–37.
  3. Farneti B, Alarcón AA, Cristescu SM, Costa G, Harren FJM, Woltering EJ. Chilling-Induced Changes in Aroma Volatile Profiles in Tomato. Food Bioprocess Technol. 2015;8:1442–54.
  4. Misael O. Vega-Garcı´a, Greici L´opez-Espinoza JCO, Jos´e J. Caro-Corrales, Francisco Delgado Vargas and JAL-V. Changes in Protein Expression Associated with Chilling Injury in Tomato Fruit. J Am Soc Hortic Sci. 2010;135:83–9.


Summer Salad + Dressings

Two weeks ago at the market, we sampled a kale and blueberry salad and taste tested some different homemade salad dressings.

One cup of cooked kale contains 1328% of your daily vitamin K and 354% of your daily vitamin A. Kale has anti-cancer and detoxifying properties. Kale contains over 45 different flavonoids, which have antioxidant and anti-inflammatory benefits. Blueberries are similarly rich in antioxidants.

Additionally, many delicious salad dressings can be made from ingredients we already have in our cupboard and we hope these recipes inspire some salad dressing creativity!

Salad Dressings – Olive Oil Vinaigrette and Mustard Vinaigrette

Kale Salad and Honey Garlic Vinaigrette