Health Benefits and Nutritional Value of Zucchini (Cucurbita pepo)

Zucchini (Cucurbita pepo), also known as courgette, belongs to the Cucurbitaceae family (the gourd family).

It is a type of summer squash cultivated for its edible fruit, which is usually cylindrical in shape and dark green in color.

Some varieties differ in size, shape, and shade, ranging from light green to almost black.

Zucchini is widely grown in home gardens and sold in markets.

Both the fruit and the flowers are edible — the flowers are sometimes eaten fried.

When buying zucchini, it’s best to avoid old or overly ripe ones, which tend to have large seeds, dry flesh, and dull skin.

Nutritional Composition of Zucchini

The following table shows the nutrients contained in 100 grams of raw zucchini:

Nutrient	Amount per 100 g
Calories	21 kcal
Carbohydrates	4.21 g
Fiber	1.1 g
Sugars	3.16 g
Protein	1.05 g
Fat	0 g
Sodium	0 mg
Calcium	21 mg
Potassium	222 mg
Vitamin C	12.6 mg
Iron	0.44 mg
Cholesterol	0 mg

Nutritional Benefits

1. Rich Source of Antioxidants

Zucchini is abundant in plant-based antioxidants, particularly carotenoids such as:

• Lutein

• Zeaxanthin

• Beta-carotene

These compounds help reduce oxidative damage caused by free radicals.

According to a 2016 Annual Review of Nutrition, lutein and zeaxanthin accumulate in the retina, enhancing vision and reducing the risk of age-related macular degeneration (AMD) — a leading cause of vision loss among older adults.

2. Good Source of Dietary Fiber

Zucchini contains both soluble and insoluble fiber, which offer many digestive and metabolic benefits:

• Soluble fiber nourishes beneficial gut bacteria, leading to the production of short-chain fatty acids (SCFAs) that help reduce inflammation and support intestinal health.
  This may ease symptoms of conditions like Crohn’s disease, Irritable Bowel Syndrome (IBS), and ulcerative colitis.

• Insoluble fiber promotes healthy bowel movements.

• Its high water content also helps prevent constipation by softening stool.

A high-fiber diet is associated with a lower risk of heart disease, improved digestion, and better weight management.

3. Source of Vitamins

Zucchini provides several essential vitamins, including:

• Vitamin C — an important antioxidant that supports immune function and collagen synthesis.

• Vitamin B6 — crucial for metabolism and brain health.

• Smaller amounts of Vitamin A, folate, Vitamin B1 (thiamine), and Vitamin B2 (riboflavin).

4. Source of Minerals

Zucchini is rich in key minerals such as:

• Manganese, which supports collagen production and brain and nerve function.
  It also aids in the synthesis of choline, a nutrient important for liver health.

• Potassium, which helps regulate blood pressure and maintain electrolyte balance.

Scientific Studies on Zucchini Benefits

• A 2017 laboratory study published in Nutrients showed that zucchini extracts may inhibit cancer cell growth by inducing apoptosis (cell death) and preventing cell proliferation.

• A 2020 study on rats, published in Food and Nutrition Sciences, found that zucchini consumption reduced markers of coronary heart disease (CHD), such as total cholesterol, LDL cholesterol, and triglycerides.
  However, more human clinical studies are needed to confirm these effects.

Potential Health Benefits

1. Weight Management

Regular zucchini consumption may support weight loss because it is:

• Low in calories

• High in water

• Rich in fiber, which promotes fullness and reduces appetite

A 2015 systematic review of 17 studies published in PLoS One found that a diet rich in fruits and non-starchy vegetables (like zucchini) was associated with greater weight loss and lower long-term weight gain.

Note: No single food causes weight loss alone — maintaining a balanced diet and regular physical activity is key.

2. Skin Health

Zucchini benefits the skin mainly due to its high vitamin C content, which:

• Promotes collagen production, the protein that maintains skin firmness.

• Helps reduce sun-induced skin damage and signs of aging.

• Enhances antioxidant levels in the body, protecting skin cells from oxidative stress.

3. Heart Health

Because zucchini is rich in potassium and fiber, it can help:

• Regulate blood pressure

• Reduce cholesterol levels

• Lower the risk of cardiovascular disease

Safety and Side Effects

1. General Safety

Zucchini is safe to eat raw or cooked in most cases.

However, in rare instances, some zucchini may taste bitter due to compounds called cucurbitacins, naturally found in gourds.

High levels of cucurbitacins — usually found in non-commercial or wild varieties — may cause:

• Nausea and vomiting

• Diarrhea

• Hair loss

• In extreme cases, serious toxicity or death

Studies (e.g., Pharmacognosy Reviews, 2015; JAMA Dermatology, 2018) reported such risks, though commercially sold zucchini typically contains very low and safe levels.

2. Allergies

According to the American College of Allergy, Asthma, and Immunology (ACAAI), individuals with Oral Allergy Syndrome (OAS) may experience symptoms like mouth or throat itching after eating raw zucchini.

Cooking zucchini usually prevents these reactions.

Anyone experiencing allergic symptoms should seek medical advice.

Summary

Zucchini is a nutrient-dense, low-calorie vegetable that offers numerous health benefits, including:

• Supporting eye health through carotenoids

• Improving digestion and gut health

• Promoting heart and skin health

• Aiding weight management

It is generally safe, versatile, and can be enjoyed raw or cooked in many dishes — making it a valuable part of a balanced diet.