Zucchini, also called courgette in some parts of the world, is believed to have been first cultivated up to 10,000 years ago! Originally grown in parts of South America, at the time it was primarily grown for its beneficial seeds since the wild variety didn’t have much flesh and tasted very bitter. In fact, the ancient zucchini vegetable didn’t even have much resemblance to the kind that we see available in most supermarkets today.
A favorite among low-carb dieters and anyone who wants to lose weight fast, zucchini has a very low score on the glycemic index. Due to its high water percentage, zucchini is low in calories, carbs and sugars, but high in essential nutrients like potassium, manganese, and antioxidants like vitamin C and vitamin A. To add more filling volume to your meals with little extra calories, you can use zucchini in a variety of different cuisines and recipes: a healthy raw snack, dip, side dish or even vegetarian entrée (see recipe suggestions at bottom).
Zucchini Nutrition Facts
Even though most people use zucchini like other vegetables — for example, adding it to savory dishes with herbs and protein sources — botanically speaking, it’s actually a fruit. Zucchini belongs to the species Cucurbita pepo and is related to certain other squashes and pumpkins.
All summer squashes are members of the Cucurbitaceae plant family, which includes squash relatives like melon, spaghetti squash and cucumbers. These all have similar large seeds and grow above the ground on short plants. Zucchini can come in dark, light green or white spotted varieties and is also closely related to the hybrid vegetable known as yellow squash (or “summer squash”) that has a bright golden or deep-orange color.
Indeed, zucchini is a type of squash vegetable, so it has a lot in common with other squashes, including butternut and winter squash. Squashes come in two types: winter and summer. While both types share some similarities and benefits, there are a few major differences. Summer squash, including green zucchini and yellow squash, are lower in calories and much lower in natural sugars and starch, so they have lower scores on the glycemic index. All summer squash are technically picked before they fully ripen and become hardened. Both types of squash groups are a good source of vitamin A and vitamin C, plus potassium and fiber.
One medium zucchini (or about 1 ½ cups of raw slices) has about:
- 33 calories
- 0 fat
- 2 grams fiber
- 2 grams protein
- 5 grams carbs
- 3 grams sugar
- 3 milligrams vitamin C (56 percent DV)
- 4 milligrams vitamin B6 (21 percent DV)
- 3 milligrams manganese (17 percent DV)
- 3 milligrams riboflavin (16 percent DV)
- 514 milligrams potassium (15 percent DV)
- 57 milligrams folate (14 percent DV)
- 4 milligrams vitamin K (11 percent DV)
9 Zucchini Nutrition Benefits
1. High Source of Antioxidants and Vitamin C
Seeds from various squash vegetables are known to hold many types of phytonutrients that can help fight inflammation and oxidative stress. Some of these antioxidants include vitamin C, vitamin A, superoxide dismutase (SOD), glutathione peroxidase (GSHpx) and glucose-6-phosphatase (G6Pase). In many nations, summer squash is a primary source of carotenoid antioxidants, including alpha-carotene and beta-carotene. Much of the antioxidant content is held within zucchini’s skin, so it’s a good idea not to peal your squash.
One medium zucchini has over 50 percent of your daily vitamin C needs. Vitamin C foods can help maintain the crucial lining of your blood cells, lower blood pressure, and protect against inflammation and clogged arteries. Seeds from squash plants also have a long history of use in traditional and folk medicines when it comes to immune system boosting. Historically, seeds from squash were believed to be antimicrobial and offer antiparasitic properties, so populations believed that zucchini nutrition positively benefited gut, nervous, immune and cardiovascular systems.
One 2006 study that investigated the effects of squash seeds (from pumpkin) on immune function found that the raw seeds were effective in alleviating detrimental effects associated with protein malnutrition, free radical damage and oxidation. Pumpkin seed protein isolates hold components that have anti-peroxidative properties that can help improve liver function and detoxification, and researchers believe that, to a somewhat lesser extent, similar benefits exist within seeds of other squash varieties like zucchini.
2. Has Anti-Inflammatory Properties that Can Improve Heart Health
Zucchini and other squashes are largely made of water and carbohydrates, specifically the type called polysaccharides. Summer squash includes a good percentage of the fiber called pectin, which is a type of beneficial polysaccharide that is linked to improved cardiovascular health and the ability to lower cholesterol naturally. Pectin fiber, which is also found in apples and pears, is known to improve arterial health and reduce disease-causing inflammation, so it might also offer protection against diabetes and insulin resistance.
And since obesity and heart disease risk factors are often linked, it’s beneficial that zucchini can help support weight loss. Studies show that low-sugar and low-carb diets can be effective in bodyweight management since they positively impact insulin and other hormones. Of course, there are other factors to consider, especially how many healthy sources of fats and fresh whole fruits someone consumes, but zucchini can definitely play a role in a heart-healthy diet that also improves bodyweight.
3. High Source of Potassium
Zucchini is high in the heart-healthy mineral potassium. One cup of cooked zucchini gives you more than 15 percent of your daily value, which is usually more than what’s included in the typical multivitamin supplement!
Research suggests that low potassium is tied to imbalances with other minerals that can raise the risk for heart disease and other complications. Potassium can also be a natural way to lower blood pressure because it counteracts the effects of a high-sodium diet. Increasing potassium intake can slash your stroke risk and may also lower your odds of developing heart disease.
4. Help Improve Digestion
Zucchini and other types of summer squash are often recommended for digestive issues and diverticulitis since they’re hydrating and provide essential electrolytes and nutrients. Research suggests that zucchini also offers anti-inflammatory protection within the GI tract that can reduce IBS, ulcer-related symptoms and leaky gut syndrome.
There is now mounting evidence to indicate that a compromised epithelial barrier is associated with low-grade immune activation and intestinal dysfunction that can lead to IBS symptoms in some patients. Eating anti-inflammatory foods, such as plenty of non-starchy fresh vegetables, is the first step to lowering body-wide inflammation and gut-related issues.
Zucchini are also very easily digested since they’re largely water, plus they also offer some dietary fiber that can bring natural constipation relief or help treat diarrhea. To obtain the biggest digestive boost, eat the whole vegetable, including the nutrient-rich seeds and skin. You can even add some raw zucchini to your favorite Green Smoothie Recipes.
5. Low in Calories and Carbs
One of the best things about squash is that they are very high in water. While calorie counting is crazy and not the best way to aim for weight loss, including tons of non-starchy veggies in your diet is an effective strategy.
Zucchini has a low calorie count and helps to fill you up — since you can eat a whole lot at once for little calories. Zucchini are also one of the lowest carb-containing veggies, second to leafy greens. This is one reason why people like to use them in place of noodles or other carbs.
6. Helps Maintain Eye Health
All types of summer squash (and winter squash, too) offer a good dose of phytonutrients like vitamin C, manganese, beta carotene, lutein and zeaxanthin that protect eye health. Lutein and zeaxanthin are two types of carotenoid antioxidants found in zucchini that often get attention for defending the eyes from age-related diseases, thus offering natural treatment for macular degeneration, cataracts and glaucoma. They work by protecting the retina, cornea and macula from UV light damage and oxidative stress that can lead to loss of vision and even blindness. In addition to protecting the delicate tissues of eyes, they can keep skin youthful and free from signs of aging, too.
7. Good Source of Energizing B Vitamins
Zucchini is high in B vitamins, including folate, vitamin B6 and riboflavin. B vitamins help support a healthy metabolism since they aid in protein, carbohydrate and nucleic acid metabolism. Obtaining enough B vitamins is important for cognitive health, maintaining an upbeat mood and preventing fatigue.
Folate specifically is tied to cell growth and aids in tissue development and maintenance. Zucchini nutrition is beneficial for women looking to conceive or who are pregnant because folate allows your body to synthesize new DNA and properly conceive. It’s also crucial for a healthy pregnancy because it helps prevent birth defects and developmental problems.
8. Can Help Control Diabetes
Apart from weight loss and increase in physical activity, the development of type 2 diabetes can be prevented by dietary changes. Because zucchini are low in carbs and sugar, and both filling and nutrient-dense, they can play a role in diabetes prevention. (They’re also a good choice for any healthy weight loss program for the same reason.)
The polysaccharide fibers found in zucchini and other squash, including pectin, have special benefits for blood sugar regulation. For anyone struggling with diabetes, zucchini can help combat problems controlling blood sugar levels since they’re a very low-carb, low-glycemic veggie that helps prevent insulin spikes and dips.
The state of prediabetes is characterized by an increase in insulin resistance and a decrease in pancreatic beta cell function. The early stages of type 2 diabetes can be identified by an impaired glucose tolerance or by an impaired fasting blood sugar. Research shows that a diet with high dietary fiber intake of more than 30 grams per day can be a simple and effective preventive approach.
Consuming high-fiber foods has many positive effects on the physical health status in addition to blood sugar control. It also positively impacts the gastrointestinal tract, has potential to support weight reduction, and can improve disturbances of carbohydrate and fat metabolism that might lead to heart disease.
9. Might Help Balance Thyroid and Adrenal Function
A 2008 study done by the Endocrine Research Unit at Devi University in India found a high presence of polyphenols and ascorbic acid in extracts taken from the peel of zucchini and other squash vegetables. When the researchers tested the effects of using these extracts in rats studies, the group supplementing with squash extract showed beneficial effects in regard to thyroid, adrenal and insulin regulation. They attributed these improvements to the antioxidant effects of squash’s phytonutrient chemicals.
History of Zucchini and Interesting Facts
Like all types of squash, zucchini has its ancestry in the Americas. The modern varieties of squash typically called “zucchini” were actually developed in Italy hundreds of years after their original species was first cultivated in parts of South America. Records show that wild squash plants first grew in South America and then spread throughout Central and North America, before being brought back to Europe by Christopher Columbus himself!
When shopping for zucchini, you might see it called by a few different names, including crookneck, summer squash or pattypan. Look for zucchini at farmers’ markets and in nearly any grocery store, usually year-round. It’s naturally at its peak during the warmer months, usually throughout the summer (hence its name!).
Most of the time, zucchini are picked when they are considered to still be “immature,” but a fully ripe zucchini can grow to be the size of a typical baseball bat! Since zucchini is high in water and absorbs a high percentage of the compounds from the soil it grows in, purchasing organic summer squash is the best way to obtain plenty of nutrients and lower your risk of contaminants and pesticides.
Around the world, it’s one of the most versatile and loved veggies there is. In Italy, zucchini is served in a variety of ways: fried, baked, boiled, in pasta, on pizza and many other ways. Zucchini blossoms (the flowers it grows from) are also a popular ingredient. While grocery stores in the U.S. don’t usually sell the blooms, you can find them at farmers’ markets and prepare them by stuffing or panfrying them.
In France, zucchini is a key ingredient in ratatouille, a signature stew of summer fruits and vegetables prepared in beneficial olive oil. In Turkey, zucchini is the main ingredient in a popular recipe for “zucchini pancakes.” In Bulgaria, zucchini is often fried and then served with a dip made from yogurt, garlic and dill. And in Mexico, zucchini flowers are stuffed or added to quesadillas, fajitas or chili.
How to Cook With Zucchini
There are lots of ways to easily enjoy raw and cooked zucchini. Grilling zucchini is a good option, especially since this vegetable is at its peak during the hot summer months. You can also slice raw zucchini and use it to dip in guacamole, hummus or other healthy spreads. A clever way to reap the benefits of zucchini that you might not have thought of? Just like you’d use mashed bananas in bread or muffin recipes to add moisture, try using finely diced zucchini strands instead.
Using wide zucchini ribbons or thinner “spiralized noodles” in place of regular wheat pasta or lasagna noodles is another good choice for cutting down on refined carbs. Finally, don’t forget to try cooked squash as a salad topper or an ingredient to add healthy volume to any stir-fry, soup, omelet or “lettuce” wrap.
To cook zucchini, you can either roast, grill, saute, broil or steam the squash. It cooks pretty quickly and can become limp and watery when overcooked, so keep an eye on it since it quickly dispels its water and seeds while shrinking up. Some evidence suggests that squash can retain more of its antioxidants when it’s steamed, as opposed to cooked at higher temps. Steaming is considered a delicate cooking method that can preserve zucchini’s phytochemicals better than microwaving or deep frying, for example.
Healthy Zucchini Recipes
Zucchini’s mild flavor is complemented well by lots of different flavors and spices. Try adding garlic, olive oil, tomatoes, oregano, parsley, sesame and ginger to zucchini.
This Zucchini Lasagna Recipe is grain-free, healthy and delicious. Try this little twist on a classic recipe.
Total Time: 45 minutes
- 2 1/2 pounds grass-fed ground beef
- 1 red onion diced
- 4 garlic cloves, crushed
- 2 tablespoons oregano
- 2 tablespoons basil
- 1/2 teaspoon cayenne pepper
- 1/2 teaspoon sea salt
- 2 tablespoons olive oil
- 3 cups diced tomatoes
- 6 ounces tomato paste
- 1 cup black olives sliced
- 6 zucchini thinly sliced
- 1 cup raw cheese, shredded
- Preheat oven to 350 degrees F. In a large pot, sauté onions and garlic in the olive oil for about 3 minutes.
- Add ground beef and brown. Add in all dry ingredients. Mix in diced tomatoes and tomato paste.
- In a greased 9 x 13 baking dish, place a layer of sliced zucchini and then ladle on a thick layer of the meat mixture and top with the sliced black olives. Top meat and olive layer with another layer of sliced zucchini and top with a final layer of the remaining meat mixture.
- Top with shredded cheese. Cover tightly with aluminum foil. Bake for 30 min.
Interactions and Concerns of Zucchini
Zucchini is well-tolerated by most people and isn’t likely to cause digestive issues or allergic reactions. It’s even suitable for babies, toddlers and children since it’s soft, mild-tasting and easy to disguise in recipes. One potential issue is that a small percentage of zucchini and yellow squash grown in the U.S. are “genetically engineered,” according to the Environmental Working Group. Since U.S. law does not require labeling of genetically engineered produce, if you want to make sure to avoid all engineered products, you should purchase organically grown produce whenever possible or items bearing the “Non-GMO Project Verified” label.
Summer squash does contain measurable amounts of oxalates, which are natural substances found in plants and other foods that can cause health problems in people with certain existing conditions. If you have untreated kidney or gallbladder problems, you might want to avoid zucchini or speak with your doctor since oxalate foods can sometimes complicate these issues due to their impact on calcium absorption within the body.