Chard: the Mediterranean vegetable between tradition, nutrition and sustainability

From antiquity to the modern table: history of a resilient vegetable

Chard has its roots in the basin of  Eastern Mediterranean, where wild forms of  Beta vulgaris were already known in pre-classical times. Greeks and Romans especially appreciated the leaves, used both as food and as a medicinal plant, particularly to aid digestion and as a remedy against intestinal disorders (Dalby, 2003). Pliny the Elder mentions chard as a common vegetable in Roman dining halls, distinguishing between broad-leaf and thick-stemmed varieties (Naturalis Historia, Book XIX).

In the Middle Ages, the cultivation further spread in  monastic gardens, assuming a central role in the daily diet of European rural populations, where it was considered ‘food of the poor’ due to its abundance and ease of preservation. Symbolic references are not lacking: in some Italian popular traditions, chard was considered an emblem of sobriety and longevity, while in Liguria it was used in spring garden blessing rituals.

Botany and seasonality: the strength of Beta vulgaris

The chard belongs to the family of  Amaranthaceae (previously classified in Chenopodiaceae). It is a biennial herbaceous plant, cultivated as an annual, characterized by:

• leaves broad, green or dark green, sometimes blistered;

• ribs fleshy, white or colored;

• taproot system that can reach 50-70 cm in depth.

They are mainly distinguished as:

• rib chard (or 'ribs'), with developed and fleshy veins;

• cutting chard (or 'herbs'), more tender, harvested multiple times for successive shoots.

From a seasonal point of view, chard is available almost all year round, with optimal production in  autumn, winter and spring, thanks to good resistance to low temperatures (down to -2/-3°C) and germination already at 6-8°C.

Beyond white: the color diversity of chards

Although the white-ribbed variety is the most widespread in large-scale retail, there is growing interest in rainbow chards (rainbow chard), characterized by ribs in bright colors: bright yellow, ruby red, orange and pink. This variability is not only ornamental but reflects a different composition of phytonutrients:

• red/purple rib chards: are particularly rich in betacyanins, the same antioxidant pigments as beetroot, effective in counteracting oxidative stress;

• yellow/orange rib chards: have a higher concentration of betaxanthins and carotenoids, precursors of vitamin A.

The introduction of these varieties in crop rotations organic not only promotes the resilience of agricultural ecosystems but offers consumers and collective catering an opportunity to diversify the intake of phenolic compounds through color selection.

Sustainable and organic cultivation

Chard adapts to a wide range of  Italian terroirs, preferring fresh, well-drained soils rich in organic matter, with an optimal pH between 6.5 and 7.5. It is widely cultivated in:

• Po Valley (Emilia-Romagna, Lombardy, Veneto);

• Tyrrhenian and Adriatic coastal areas (Lazio, Campania, Puglia);

• peri-urban gardens and systems of  organic farming.

From an agronomic point of view, beetroot is appreciated for:

• short crop cycle (60-90 days from sowing);

• reduced water requirement compared to other leafy vegetables (350-400 mm/cycle);

• good integration in  sustainable crop rotations as a renewal crop;

• ability to improve soil structure thanks to the deep root system.

In  organic farming, beetroot lends itself to integrated weed management techniques through natural mulching and mechanical hoeing, as well as organic fertilizations with compost and mature manure, contributing to low environmental impact production systems (ISMEA, 2023). Its hardiness also makes it ideal for theurban agriculture and educational gardens.

Nutritional profile: a concentrate of folates and vitamins

According to the food composition tables of  CREA, raw chard Beta vulgaris, cultivar Chard, has a high content of  Water (93.3%). (CREA, 2024). 100 grams of this vegetable provide:

• energy: 15 kcal;

• carbohydrates: 1.8 g;

• proteins: 1.3 g;

• dietary fiber: 1.2 g.

As regards to vitamins, raw chard is rich in:

• folates (vitamin B9): 85 μg/100 g, equal to 42.5% of the Nutritional Reference Value indicated in Annex XIII to Regulation (EU) No 1169/11;

• vitamin A retinol equivalent: 263 μg/100 g, equal to 32.9% of the NRV;

• vitamin C: 24 mg/100 g, equal to 30% of the NRV.

The presence of oxalic acid in chard suggests moderate consumption for those suffering from kidney stones, although boiling drastically reduces its content (however promoting the loss of some water-soluble vitamins, such as C and folates). It is also recommended to combine chard with a few drops of lemon to maximize the absorption of non-heme iron present in the leaves.

‘Evidence-based health’: nitrates, betalains and cognitive protection

Peer-reviewed scientific studies attribute to chard and other  green leafy vegetables various potential health properties, related to the presence of:

• polyphenols and flavonoids (including kaempferol, quercetin, vitexin), with demonstrated antioxidant and anti-inflammatory activity;

• betalains (betanin, vulgaxanthin), bioactive compounds with neuroprotective properties. A systematic review identified 192 bioactive compounds in chard, of which betalains represent 20% (Gamba et al., 2021);

• natural nitrates (up to 250 mg/100 g), associated with increased bioavailability of nitric oxide, lowering blood pressure and improving endothelial function. These effects could translate into a reduction in the risk of cardiovascular diseases and mortality (Tan et al., 2024);

• phenolic compounds such as coumaric acid and rosmarinic acid, with inhibitory activity on α-glucosidase and α-amylase enzymes, potentially useful in glycemic regulation (Boukhris et al., 2019).

Regular consumption of leafy green vegetables has been associated with:

• reduction of cardiovascular risk of 15.8% according to a 2024 meta-analysis (Pollock et al., 2016); a recent meta-analysis has also suggested the potential of consuming leafy green vegetables rich in natural nitrates to reduce the risk of cardiovascular diseases (Tan et al., 2018);

• support to  carbohydrate metabolism and improvement of insulin sensitivity, with inverse associations between fruit and vegetable consumption and risk of type 2 diabetes (Aune et al., 2017);

• contribution to the maintenance of  intestinal health thanks to the prebiotic action of fiber (Boeing et al., 2012);

• slowing of  cognitive decline related to age: a prospective study on 960 adults showed that the consumption of about 1 serving per day of leafy green vegetables is associated with a slowing of cognitive decline equivalent to being 11 years younger, thanks to the content of phylloquinone (vitamin K), lutein, folates, and kaempferol (Morris et al., 2018).

Gastronomic heritage and versatility in the kitchen

Swiss chard is extremely versatile in  traditional Italian cuisine. It is used:

• boiled or sautéed as  side dish with garlic and oil;

• as an ingredient of  fillings (Liguria savory pies such as ‘torta pasqualina’, ravioli, cannelloni);

• In  soups and traditional soups (Tuscan ribollita, minestrone);

• as a base for regional preparations, for example combined with legumes (chard and beans) or fresh cheeses (chard alla parmigiana);

• in omelettes and soufflés.

The younger leaves of cut chard are also suitable for raw consumption in  mixed salads, while the stalks are suitable for longer cooking, steaming, or baked au gratin.

Conclusions

In conclusion, chard represents the archetype of the Mediterranean functional food: accessible, versatile, and inherently sustainable. Its ability to improve soil structure and its climate resilience, combined with an excellent nutritional profile, make it a valuable resource for food sovereignty and public health. Enhancing chard – in its classic variants and polychrome selections – means promoting a model of conscious consumption, where agronomic tradition meets the most rigorousevidence from biomedical research.

Dario Dongo

Credit cover: Dario Dongo

References

• Aune, D., Giovannucci, E., Boffetta, P., Fadnes, L. T., Keum, N., Norat, T., Greenwood, D. C., Riboli, E., Vatten, L. J., & Tonstad, S. (2017). Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality—A systematic review and dose-response meta-analysis of prospective studies.  International Journal of Epidemiology, 46(3), 1029–1056.  https://doi.org/10.1093/ije/dyw319

• Boeing, H., Bechthold, A., Bub, A., Ellinger, S., Haller, D., Kroke, A., Leschik-Bonnet, E., Müller, M. J., Oberritter, H., Schulze, M., Stehle, P., & Watzl, B. (2012). Critical review: Vegetables and fruit in the prevention of chronic diseases.  European Journal of Nutrition, 51(6), 637–663.  https://doi.org/10.1007/s00394-012-0380-y

• Boukhris, M., Bouaziz, M., Feki, I., Jemai, H., El Feki, A., & Sayadi, S. (2019). Wild edible Swiss chard leaves (Beta vulgaris L. var.  Chard): Nutritional, phytochemical composition and biological activities.  Food Research International, 119, 612–621.  https://doi.org/10.1016/j.foodres.2018.10.039

• CREA – Council for Agricultural Research and Economics Analysis. (2024). Food composition tables. Beet, raw.  https://www.alimentinutrizione.it/tabelle-nutrizionali/005080

• Dalby, A. (2003).  Food in the ancient world from A to Z. Routledge. ISBN-13: 9780415862790

• Gamba, M., Raguindin, P. F., Asllanaj, E., Merlo, F., Glisic, M., Minder, B., Bussler, W., Metzger, B., Kern, H., & Muka, T. (2021). Bioactive compounds and nutritional composition of Swiss chard (Beta vulgaris L. var.  Chard and  flavescens): A systematic review.  Critical Reviews in Food Science and Nutrition, 61(20), 3465–3480.  https://doi.org/10.1080/10408398.2020.1799326

• Morris, M. C., Wang, Y., Barnes, L. L., Bennett, D. A., Dawson-Hughes, B., & Booth, S. L. (2018). Nutrients and bioactives in green leafy vegetables and cognitive decline: Prospective study.  Neurology, 90(3), e214–e222.  https://doi.org/10.1212/WNL.0000000000004815

• Pliny the Elder.  Naturalis Historia.

• Pollock R. L. (2016). The effect of green leafy and cruciferous vegetable intake on the incidence of cardiovascular disease: A meta-analysis.  JRSM cardiovascular disease, 5, 2048004016661435. https://doi.org/10.1177/2048004016661435

• Regulation (EU) No 1169/2011 of the European Parliament and of the Council of 25 October 2011 on the provision of food information to consumers. Consolidated text: 01/04/2025. http://data.europa.eu/eli/reg/2011/1169/2025-04-01

• Tan, L., Stagg, L., Hanlon, E., Li, T., Fairley, A. M., Siervo, M., Matu, J., Griffiths, A., & Shannon, O. M. (2024). Associations between vegetable nitrate intake and cardiovascular disease risk and mortality: A systematic review. Nutrients, 16(10), 1511. https://doi.org/10.3390/nu16101511