What is zucchini
Zucchini has made a name for itself as somewhat of an “og” superfood in the last few years, for example, zucchini pasta as a healthy alternative to traditional store-bought pasta. But what is zucchini exactly?
Zucchini (in the UK called a courgette) is a summer squash from the Cucurbitaceae plant family that also includes vegetables such as cucumbers, spaghetti squash and melons; and are believed to originate from Central America.1
Zucchini can grow up to 1 meter in length, however, it is usually harvested at the time it reaches a length of 15 to 25 cm. Typically elongated and cylindrical in shape, zucchini comes in colours varying from light to dark green, with some yellow and orange varieties being popular on the market. Zucchini is also described with pale greenish-white insides that carry a delicate, almost sweet flavour.2
They also have a lot of health benefits, with many ways to include them in your diet.
Health benefits of zucchini
Good Source of antioxidants
Most chronic diseases are caused by oxidative stress, which happens when there is a build-up of oxygen-related chemicals called oxygen-reactive species (ROS). While ROS are a natural by-product of our metabolism, too much of them can lead to the creation of free radicals, which is a primary cause of many chronic diseases, such as cancer, Alzheimer’s disease, diabetes and cardiovascular disease.3
Eating vegetables such as courgettes will help you in getting rid of free radicals from the body with the help of naturally occurring antioxidants. Zucchini is rich in phytochemicals (phyto means plant) with antioxidant properties that can prevent chronic diseases.Examples of those chemicals are phenolics, anthocyanin, carotenoids, alkaloids, lutein and zeaxanthin.1
Low-calorie food
Zucchini has a high water content and scores only 17 calories per 100 grams of product, which makes it a great addition to a weight-loss diet, as it helps you feel full without excess calories.4
Zucchini also has a high fibre content, allowing you to feel satiated for longer. Fibre in food usually means that you have to chew for longer, which sends signals to the brain, making it more aware that you are eating. It takes longer for fibre to go through the human digestive system, so the effect of fullness is even higher and keeps your appetite in check.5
Research has consistently shown that eating fruits and vegetables is a good weight loss strategy, as it has been linked to slower weight gain over time and overall smaller abdominal circumference.4,5
Zucchini is a green vegetable that is very low in starch. It has been widely documented that non-starchy greens are a staple for maintaining a healthy weight and reducing the risk of obesity.6
Good for digestion
As zucchini has a high water content, it provides great support for gut movement and soft stool formation. It helps food to pass through your digestive system and reduces the risk of constipation.7
Zucchini is a great source of dietary fibre, which has been positively linked to maintaining a healthy gut. There are two types of dietary fibre: soluble and insoluble.5
Insoluble fibre acts as a bulking agent in your stools, easing the passing process through your gut. Soluble fibre supports the bacteria in your gut. These, in turn, create short-chain fatty acids (SCFAs) that provide nutrients, mainly in your colon.8
SCFAs also have anti-inflammatory properties and reduce the risks of inflammatory bowel diseases, such as ulcerative colitis and Crohn’s disease.9
Benefits heart health
As zucchini contains fibre, it helps you in reaching your daily dietary fibre goal. In the UK, the daily recommended intake has been set to 30g. Researchers agree that eating foods high in fibre decreases the risks of cardiovascular illnesses, such as heart diseases and strokes, as it decreases high blood pressure.10,11
Fibre in vegetables like summer squash reduces low-density lipoprotein (LDL), which is commonly known as “bad” cholesterol. When LDL cholesterol levels are high, it builds up on the walls of blood vessels in form of plaques. This causes heart problems such as heart disease or strokes. In zucchini, a soluble type of fibre called pectin is the main enemy that fights LDLs.12
Zucchini is a rich source of potassium, which has been reported to decrease blood pressure, especially when your diet is very high in sodium (salt).13
To add to the benefits of using this summer squash in a heart-friendly diet is the abundance of carotenoids, such as beta carotene, lutein and zeaxanthin. It has antioxidating and anti-inflammatory properties, as well as it maintaining healthy blood vasculature.14
Lowers blood sugar levels
People with type 2 diabetes should become particularly interested in zucchini as it has been documented that it reduces blood sugar levels. It has also been shown that dietary fibre improves the work of your metabolism, as it influences glucose and insulin levels.5, 14
Fibre in green vegetables such as zucchini has been suggested to reduce the risks of type 2 diabetes, as it keeps the insulin levels stable and stops sugar spikes from happening after a meal.14, 15
Additionally, zucchini is relatively low in carbs, which, can reduce the need of taking medicine preventing sugar spikes and type 2 diabetes medication.16
Good for eye health
Beta-carotene, vitamins A and C, which are present in zucchini, are essential nutrients for good eye health and strong vision. These compounds can help in preventing unhealthy ageing of your eyes due to their antioxidative abilities.17,18
Good for bone health
Zucchini is a good source of lutein and zeaxanthin that positively contribute to the maintenance of healthy bone density.19
Anti-cancer effect
Due to the fibre and vitamin A content of zucchini, they may have great preventative abilities against some cancers including bowel, breast and lung cancer.11,14
Nutritional facts
Courgettes are low in calories (17 kcal per 100 grams of fresh produce) and high in water (95.2g per 100g), which makes them very diet-friendly. They also are a rich source of folate, potassium, vitamin A, and vitamin C.
100 grams of raw, uncooked, unsalted courgette contains around:
- Macronutrients:
- Carbs - 3g (2g of sugar:1g of fibre)
- Fat - <1g
- Protein - 1g
- Vitamins (with Daily Reference Intake in % for healthy adults)
- Vitamin A - 7%
- Beta-Carotene - 6%
- Thiamine (Vitamin B1) - 3%
- Riboflavin (Vitamin B2) - 2%
- Niacin (Vitamin B3) - 3%
- Pantothenic acid (Vitamin B5) - 6%
- Vitamin B6 - 6%
- Folate (Vitamin B9) - 7%
- Vitamin C - 16%
- Vitamin K - 4%
- Minerals (with Daily Reference Intake in % for healthy adults)
- Calcium - 2%
- Iron - 3%
- Magnesium - 5%
- Manganese - 8%
- Phosphorus - 5%
- Potassium - 6%
- Sodium - 0%
- Zinc - 3% 20
Uses of zucchini
There are multiple ways to incorporate zucchini into your diet. It can be enjoyed raw, however, it is more typical to cook it. Cooking techniques involve boiling, steaming, stuffing, grilling or frying.2
When frying zucchini, the skin is left in place for the plant to keep its shape and excess moisture is removed to support overall shape.
One of the simplest ideas to enjoy zucchini is to cook it with butter or olive oil and herbs. It is very mild in flavour, so it can become an ingredient of more complex dishes.
People incorporate courgettes in baking to make zucchini bread, in a similar fashion to banana bread or carrot cake.21
A popular way to prepare zucchini while being on a low-carb diet is to use spiraliser/cut squash thinly to create zucchini noodles (zoodles).22
Side effects and other concerns
Zucchini, as a part of the Cucurbitaceae plant family, can contain cucurbitacins (steriod toxins), that serve to protect the plant from predators. When consuming zucchini these toxins can taste bitter.23
In the agricultural industry, plants from this family are cultivated in a way that keeps those toxins low, so it is safe to eat. However, toxic squash was recorded to be both purchased in stores and home-grown.24
It is especially dangerous for people with an impaired sense of taste (especially the elderly). It is advised that young people should try the zucchini first for them.
Typically, squash poisoning presents itself in the form of digestive problems such as diarrhoea, vomiting and abdominal pain. In extremely rare cases, squash poisoning may result in death.24,25
Zucchini may also cause an allergic reaction as it contains profilin. This protein is located in the juice of a young zucchini and gets released during the process of peeling.26
Summary
Zucchini (courgette) is a summer squash that has been popularised all around the world. It is a part of traditional dishes in a variety of cultures and there are many ways in which you can incorporate zucchini into your diet according to your preferences and in ways that inspire your culinary creativity. It is usually cooked before eating and due to being very low in calories/carbs and high in water content, it makes a perfect addition to weight-loss and low sugar/diabetic diets. Zucchini is rich in antioxidants that may help in the prevention of many chronic diseases such as heart disease, high blood pressure, stroke and cancer. It also contains water and fibre that provides great support for your gut and several vitamins and minerals that sustain your bone and eye health.
References
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- Pizzino G, Irrera N, Cucinotta M, Pallio G, Mannino F, Arcoraci V, et al. Oxidative stress: harms and benefits for human health. Oxid Med Cell Longev [Internet]. 2017 [cited 2023 Apr 14];2017:8416763. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5551541/
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- Munekata PES, Pérez-Álvarez JÁ, Pateiro M, Viuda-Matos M, Fernández-López J, Lorenzo JM. Satiety from healthier and functional foods. Trends in Food Science & Technology [Internet]. 2021 Jul 1 [cited 2023 Apr 14];113:397–410. Available from: https://www.sciencedirect.com/science/article/pii/S0924224421003472
- Bertoia ML, Mukamal KJ, Cahill LE, Hou T, Ludwig DS, Mozaffarian D, et al. Changes in intake of fruits and vegetables and weight change in united states men and women followed for up to 24 years: analysis from three prospective cohort studies. PLoS Med. 2015 Sep;12(9):e1001878.
- Eating, diet, & nutrition for constipation - niddk [Internet]. National Institute of Diabetes and Digestive and Kidney Diseases. [cited 2023 Apr 14]. Available from: https://www.niddk.nih.gov/health-information/digestive-diseases/constipation/eating-diet-nutrition
- Morrison DJ, Preston T. Formation of short chain fatty acids by the gut microbiota and their impact on human metabolism. Gut Microbes [Internet]. 2016 Mar 10 [cited 2023 Apr 14];7(3):189–200. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939913/
- Parada Venegas D, De la Fuente MK, Landskron G, González MJ, Quera R, Dijkstra G, et al. Short chain fatty acids (Scfas)-mediated gut epithelial and immune regulation and its relevance for inflammatory bowel diseases. Front Immunol. 2019;10:277.
- Stephen AM, Champ MMJ, Cloran SJ, Fleith M, van Lieshout L, Mejborn H, et al. Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health. Nutr Res Rev. 2017 Dec;30(2):149–90.
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- CDC. Ldl and hdl cholesterol and triglycerides | cdc. Gov [Internet]. Centers for Disease Control and Prevention. 2022 [cited 2023 Apr 14]. Available from: https://www.cdc.gov/cholesterol/ldl_hdl.htm
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- Wang P, Fang J, Gao Z, Zhang C, Xie S. Higher intake of fruits, vegetables or their fiber reduces the risk of type 2 diabetes: A meta‐analysis. J Diabetes Investig [Internet]. 2016 Jan [cited 2023 Apr 14];7(1):56–69. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4718092/
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