Zucchini: Key Nutrients, Health Benefits and Nutrition Profile

Zucchini, also known in some parts of the world as courgette, is a type of summer squash.

It is typically served either as a vegetable or as part of recipes like ‘zucchini noodles’ and ‘zucchini pancakes.’

Consuming zucchini is a good way to increase your vitamin C intake, and it’s a moderate source of fiber, folate, manganese, and potassium.

In this article, we examine zucchini’s key nutritional properties and its potential benefits according to scientific research.

Key Nutrients

The nutrients present in the highest concentrations in zucchini include vitamin C, folate, manganese, and potassium.

Here are the amounts you’ll find in a 180g cup of sliced, cooked zucchini, according to USDA data.

Vitamin C

A cup of cooked zucchini contains 23.2 mg of vitamin C, which is 26% of the daily value.

Vitamin C has antioxidant properties and may help to limit free radical-induced damage to the human body’s cells. It may also help support the immune system.

Folate

A cup of cooked zucchini slices provides 50.4 mcg of folate, which is approximately 13% of the daily value.

Among its numerous functions, folate is necessary for DNA production and can help to support healthy pregnancies.

Manganese

A cup serving of cooked zucchini typically contains 0.31 mg of manganese, which is 13% of the daily value.

Manganese is important for energy production and helps to support health through its role in the body’s antioxidant system.

Potassium

The potassium content of cooked zucchini is approximately 475 mg per cup serving, which is 10% of the daily value.

Potassium is an essential nutrient that many people under-consume, and a sufficient intake may help support lower blood pressure.

Potential Benefits and Scientific Research

There is very little scientific research specific to zucchini, but let’s now go through what studies have found about the vegetable.

Suitability For Low-Potassium Diets

A 2025 randomized crossover trial investigated the potassium content of vegetables, including zucchini, after differing cooking methods.

Each of the vegetables used within the study was selected for being high in potassium (>201 mg per 100g).

While potassium is an essential nutrient with importance for human health, some individuals may be prescribed to follow medical low-potassium diets. Therefore, the study aimed to see how specific cooking techniques decreased potassium content.

The study found that pressure cooking zucchini resulted in the largest losses of potassium, with zucchini’s potassium content falling to 93.62 mg per 100 grams after being pressure cooked.

This shows that, despite being a moderate potassium source, zucchini may potentially fit into lower-potassium diets when pressure cooked.

However, it is just one study, and individuals following strict low-potassium diets should consult with their healthcare provider when assessing zucchini (or any other vegetable) intake.

Zucchini and Eye Health

A 2023 study presented an “ideal food pyramid” to either prevent or support eye-related health conditions.

These conditions included cataracts, macular degeneration, and diabetic retinopathy.

One of the main reasons zucchini was included in this food pyramid was for its lutein content. The authors noted that zucchini (cooked with skin) was among the vegetables with the highest lutein content, which they classed as >900 mg (milligrams) lutein per 100g.

However, this was likely a unit mistake and they presumably meant over 900 mcg (micrograms) — USDA data shows zucchini contains 2,070 mcg of lutein and zeaxanthin per cup serving.

Lutein is a carotenoid thought to support eye health. A 2021 systematic review of 46 studies found that higher intake of lutein and zeaxanthin increased macular pigment optical density (MPOD) when daily intake was over 5 mg (5,000 mcg).

MPOD is a marker of eye health, with higher levels thought to have a protective effect.

High Fiber Content Per Calorie

Zucchini contains 1 gram of fiber per 100 grams and 1.8 grams per 180-gram cup.

While this may not seem like a significant amount, zucchini is a notable fiber source compared to its total calorie and carbohydrate content.

For example, most people will have heard whole-wheat bread referred to as a good source of fiber.

The table below shows how much fiber per calorie cooked zucchini contains compared to whole-wheat bread:

Food	Fiber	Calories	Fiber per 100 calories
Cooked zucchini (100g)	1.0g	15 kcal	6.67g
Whole-wheat bread (100g)	6.0g	252 kcal	2.38g

As the table shows, zucchini has less total fiber, but it contains far higher amounts of fiber per 100 calories.

Zucchini is also significantly lower in carbohydrates than bread. This makes it a good fiber choice for individuals who are either limiting total calories or carbohydrates.

Zucchini Nutrition Facts

In the following tables you’ll see the full nutritional values for cooked courgette, presented both per 100 grams and per 180g cup (slices).

All nutritional data has been sourced from the USDA’s FoodData Central entry for cooked courgette. We have used this data alongside the FDA’s published daily values to calculate percent daily values (% DV) for each nutrient.

Calories and Macronutrients

Nutrient	Per 100g (% DV)	Per 180g cup (% DV)
Calories	15 kcal	27 kcal
Carbohydrates	2.69g (1%)	4.84g (2%)
Fiber	1.0g (4%)	1.8g (6%)
Sugars	1.71g	3.08g
Fat	0.36g (<1%)	0.65g (1%)
Saturated fat	0.07g (<1%)	0.13g (1%)
Monounsaturated fat	0.03g	0.05g
Polyunsaturated fat	0.15g	0.27g
Omega-3	0.09g	0.17g
Omega-6	0.06g	0.10g
Protein	1.14g (2%)	2.05g (4%)
Cholesterol	0 mg (0%)	0 mg (0%)

Vitamins

Vitamin	Per 100g (% DV)	Per 180g cup (% DV)
Vitamin A (RAE)	56 mcg (6%)	101 mcg (11%)
Vitamin C	12.9 mg (14%)	23.2 mg (26%)
Vitamin D	0 mcg (0%)	0 mcg (0%)
Vitamin E	0.12 mg (1%)	0.22 mg (1%)
Vitamin K	4.2 mcg (4%)	7.56 mcg (6%)
Thiamin (B1)	0.04 mg (3%)	0.06 mg (5%)
Riboflavin (B2)	0.02 mg (2%)	0.04 mg (3%)
Niacin (B3)	0.51 mg (3%)	0.92 mg (6%)
Pantothenic acid (B5)	0.29 mg (6%)	0.52 mg (10%)
Vitamin B6	0.08 mg (5%)	0.14 mg (8%)
Folate (B9)	28 mcg (7%)	50.4 mcg (13%)
Vitamin B12	0 mcg (0%)	0 mcg (0%)
Choline	9.4 mg (2%)	16.9 mg (3%)

Minerals

Mineral	Per 100g (% DV)	Per 180g cup (% DV)
Calcium	18 mg (1%)	32.4 mg (2%)
Iron	0.37 mg (2%)	0.67 mg (4%)
Magnesium	19 mg (5%)	34.2 mg (8%)
Phosphorus	37 mg (3%)	66.6 mg (5%)
Potassium	264 mg (6%)	475 mg (10%)
Sodium	3 mg (<1%)	5.4 mg (<1%)
Zinc	0.33 mg (3%)	0.59 mg (5%)
Copper	0.05 mg (6%)	0.09 mg (10%)
Manganese	0.17 mg (7%)	0.31 mg (13%)
Selenium	0.2 mcg (<1%)	0.36 mcg (1%)

Potential Drawbacks

Zucchini is a nutrient-rich vegetable that will be a positive addition to most diets.

That said, there is always the rare possibility of allergy, as there is for most foods. While zucchini allergies appear to be very uncommon, there have been documented case studies.

There have also been rare reports of hand and foot dermatitis (skin inflammation) from skin contact with zucchini.

As stated, these issues appear to be very uncommon and there are only a few reported cases. However, if anyone feels they may have an issue with zucchini, they should consult with their healthcare provider for personalized guidance.

Summary

Zucchini provides a broad range of nutrients, most notably fiber, vitamin C, manganese, folate, potassium, and copper.

However, the most notable aspect of zucchini is that a typical 180g cup serving offers this range of nutrients for just 27 calories.

Overall, it’s a flavorful vegetable that pairs well with a wide range of foods, and it can contribute valuable essential nutrients to your diet.

References