Eggplant (Solanum melongena), also known as aubergines or brinjal, is an interesting fruit (culinary vegetable) enjoyed worldwide. It is a staple in cuisines across many cultures, including Asia, the Mediterranean, and the Middle East. Today, eggplants are found in many dishes such as Asian and Mediterranean-style stir-fries. Not only do they have a unique texture and deep flavor, but they are also one of the most aesthetically pleasing foods with their deep purple skin. This fruit is both diverse in nutrition and historical background, as it dates back thousands of years (1).
Eggplant goes by several names worldwide, including “brinjal” in South Asia, “aubergine” in Europe, and “eggplant” in North America.
Read on to find out all you need to know about eggplants.
Table of Contents
Facts & History
Originating thousands of years ago, the eggplant has a remarkable history that spans a wide array of cultures. The eggplant originated on the Indian subcontinent and in Southeast Asia and has been cultivated there since prehistoric times. Dual domestication events in these areas have given eggplants a great deal of genetic diversity from their wild ancestor, Solanum insanum (1).
By the 5th century BCE, the eggplant made its way to China through trade, where it was absorbed into the cuisine and culture. The earliest record of eggplant documented in ancient Chinese literature dates back to 59 BCE (2). The Chinese appreciated eggplants for their uses in dishes and their medicinal benefits. From China, eggplants migrated to the Middle East and Africa (3). Eventually, during the Middle Ages, the eggplant was introduced to Europe by the Moors in Spain.
As eggplants made their way around, they experienced less genetic mixing compared to other members of the Solanaceae family (tomatoes, peppers). The limited migration enabled eggplants to keep most of their local traits, resulting in a rich diversity of different shapes, sizes, and colors. They can be round or oval or long and thin, with colors from the commonly known dark purple to white, green, and even stripes (1).
Fun Fact: Eggplants studied from China, Spain, and Sri Lanka have been found to have wide differences in appearance and genetics mainly due to geographic isolation.
Nutrition Facts
Beyond being a delicious food, eggplants contain a wide array of nutrients that promote health. Not only are eggplants low in calories, but they are high in vitamins, minerals, and antioxidants. They have an excellent nutritional profile that aids the body in a variety of ways.
Macronutrients
For every 1 cup (82 grams) of raw eggplant, there are the following macronutrients (4):
- Calories: 20.5 calories (kcal)
- Protein: 0.804 grams (g)
- Total Fat: 0.148 grams (g)
- Carbohydrate: 4.82 grams (g)
- Fiber: 2.46 grams (g)
Eggplants are a great source of fiber that keeps things moving in the digestive tract and helps to keep blood sugar levels from spiking. They are low in calories and fat, making them a great option for those trying to maintain a healthy weight.
Vitamins & Minerals
For every 1 cup (82 grams) of raw eggplant, there are the following vitamins and minerals (4):
- Potassium: 188 mg (5% Daily Value – DV)
- Folate: 18 mcg (4% DV)
- Magnesium: 11.5 mg (3% DV)
- Vitamin C: 1.8 mg (2% DV)
- Vitamin E: 0.246 mg (2% DV)
- Vitamin K: 2.87 mcg (2% DV)
- Phosphorus: 19.7 mg (2% DV)
- Vitamin A: 18.9 IU (1% DV)
- Calcium: 7.38 mg (1% DV)
- Choline: 5.66 mg (1% DV)
- Iron: 0.189 mg (1% DV)
- Lutein + zeaxanthin: 29.5 mcg
- Beta-carotene: 11.5 mcg
Potassium is critical for maintaining heart health, nerve function, and muscle contractions. It also aids in regulating blood pressure levels by balancing out the effects of sodium and relaxing the walls of the blood vessels, which lowers the risk of hypertension and stroke (5).
Folate is crucial for DNA synthesis and repair, which is especially necessary during times of rapid growth, including pregnancy and infancy. Getting enough folate is known to decrease the risk of neural tube defects during the development of a fetus (6).
Vitamin K is essential for blood clotting and bone metabolism. It helps keep your bone density intact and decreases the likelihood of fractures (7).
Vitamin C is a potent antioxidant that aids in immune support, collagen synthesis, and iron absorption from plant-based sources (8, 9, 10).
Plant Compounds
Eggplants are rich in several plant compounds, specifically polyphenols like phenolic acids and flavonoids. These have strong antioxidant properties, which have been found to help combat health-compromising free radicals that may damage cells in the body (11).
Anthocyanins: The skin of eggplants contains the predominant anthocyanin, nasunin. Nasunin is the major anthocyanin in eggplants (12). It is also what provides the skin of eggplants with their deep purple hue. Additionally, nasunin has been demonstrated to be excellent at preventing damage to cell membranes due to its antioxidant activity (12).
Chlorogenic Acid: Chlorogenic acid is a phenolic compound and one of the strongest free-radical scavengers present in eggplants, which has been correlated with decreased inflammation and risks of heart disease and diabetes (13, 14).
Flavonoids: Quercetin and kaempferol are examples of flavonoids found in eggplants that provide anti-inflammatory and antioxidant properties.
Summary: Eggplants contain a wide variety of fiber, vitamins, minerals, and antioxidants and are relatively low in calories. This includes nasunin and chlorogenic acid. This makes them an excellent, nutrient-dense food to incorporate into a healthy balanced diet.
Eggplant Health Benefits
Eggplants have many health benefits for the body, backed up by research. Here are some of them:
1. High in Antioxidants
Eggplants are high in antioxidants, which are compounds that help protect your cells from oxidative damage caused by free radicals. Oxidative stress has been associated with aging and the development of several diseases, such as heart disease and cancer (15).
Nasunin: Nasunin is one of the anthocyanins that have been shown to protect lipids (fats) in the membranes of brain cells from damage, potentially preventing neurodegenerative disorders (12). Nasunin is also an iron chelator, meaning it removes excess iron from the body that can form free radicals.
Chlorogenic Acid: Chlorogenic acid is a phenolic compound with anti-inflammatory, antimicrobial, and antiviral properties. It has also been found to decrease LDL cholesterol levels and may reduce the risk of heart disease (13).
The way eggplants are cooked can influence their antioxidant content. Research has shown that grilling, boiling, and sautéing increases the beneficial phenolic compounds available, particularly when they are cooked with extra virgin olive oil (16, 17).
2. Supports Heart Health
Eggplants help promote heart health in a few different ways:
Regulation of Blood Pressure: The potassium found in eggplants aids in the balance of electrolytes and fluid levels, which is necessary for maintaining normal blood pressure. Potassium promotes the relaxation (vasodilation) of blood vessels, reducing tension in the walls of the blood vessels (5).
Lowers Cholesterol Levels: Some studies suggest that the phenolic compounds in eggplants may help lower cholesterol levels in the blood, potentially reducing the risk of atherosclerosis (18).
Anti-inflammatory Effects: Anthocyanins have been found to reduce inflammation, which is a major contributor to heart disease. Eggplant specifically has been found to reduce inflammatory markers and oxidative stress, thanks to the anthocyanins it contains (19).
3. Aids in Blood Sugar Regulation
Eggplants help with blood sugar management:
Fiber: With a high amount of soluble fiber, eggplants slow digestion and absorption of sugar in the blood, which prevents sugar spikes (20, 21).
Polyphenols: These compounds can increase insulin secretion and improve insulin sensitivity, both of which are important components of blood sugar control. They also decrease the activity of enzymes involved in glucose absorption (14).
4. Promotes Digestive Health
The fiber found in eggplants helps maintain a healthy digestive system by:
Promoting Regular Bowel Movements: Fiber adds bulk to the stool, which helps it move through the digestive tract and prevents constipation (22).
Gut Health: Fiber serves as a prebiotic, meaning it feeds the good bacteria in your gut. Having a healthy gut microbiome has been associated with enhanced immunity, better nutrient absorption, and decreased inflammation (23).
Summary: Eggplants provide a high number of antioxidants that guard against cell damage, enhance heart health by maintaining blood pressure and cholesterol levels, help blood sugar control with fiber and polyphenols, and aid in digestive health by promoting regularity and serving beneficial gut bacteria.
Potential Risks & Side Effects
In general, eggplants are safe and healthy for the majority. However, there are some potential risks and side effects, including:
- Allergies and Sensitivities: Eggplants may cause allergic reactions in some people, which is rare. Those with reported allergies to other nightshade vegetables (tomatoes, peppers, or potatoes) are more likely to be allergic to or sensitive to eggplants. Symptoms may include itchiness, hives, throat swelling, and nausea, and can even lead to anaphylaxis in severe cases. Consult a healthcare professional if you experience any allergic symptoms from eating eggplant (24).
- Histamine Intolerance: For those with histamine intolerance, eggplants can trigger several symptoms due to their biogenic amine content. Biogenic amines in eggplants, including histamine, putrescine, and spermidine, may cause adverse effects in those with histamine intolerance. Symptoms that may arise include headaches, flushing, hives, digestive symptoms, and nasal congestion. Consuming them in high amounts can increase the risk of histamine intolerance symptoms. Cooking them thoroughly may lower the biogenic amine content and reduce this reaction (25).
- Solanine Levels: Eggplants are part of the nightshade family, which means they contain solanine, a glycoalkaloid that could be toxic in high doses. Solanine poisoning is uncommon and generally linked with excessive intake of green potatoes, not so much eggplants. Symptoms of solanine poisoning may include gastrointestinal upset, neurological issues, and, in extreme cases, hallucinations. The average risk with normal culinary uses of eggplants is low (26).
- Residues of Pesticides: Eggplants may have pesticide residues, and some samples have been reported with residues exceeding maximum residue limits, which can cause concern among consumers. To minimize exposure, wash eggplants with running water and peel the skin. Another option is to purchase them from organic sources (27).
- Browning Naturally: The flesh of cut eggplants may brown rapidly because it contains high levels of chlorogenic acid that undergoes oxidation by polyphenol oxidase enzymes. This browning isn’t harmful but can make the eggplant visually unappealing. To minimize browning, store cut eggplant in water with a little bit of lemon juice or vinegar mixed in (28).
- Kidney Stones: Oxalates may contribute to kidney stones in some people. Those with a history of oxalate kidney stones may need to moderate their intake of high-oxalate foods. While eggplants are not particularly high in oxalates compared to other foods, individuals prone to kidney stones should consult with a healthcare provider about their diet (29).
- Drug Interactions: Eggplants contain a small amount of vitamin K, which plays a role in blood clotting. While eggplants provide only about 2% of the Daily Value for vitamin K per serving, those on blood thinners such as warfarin should maintain consistent vitamin K intake and consult their healthcare provider for personalized advice.
Summary: Eggplant is generally safe for the majority of the population. However, those with allergies, histamine intolerance, or who are prone to kidney stones should be cautious. Many of these risks can be reduced with proper preparation like washing and cooking.
How Can You Pick Out Fresh Eggplant?
To pick out eggplants, choose ones that have:
- Firmness: It should be firm to the touch but not hard. When you press the skin with your thumb, it should spring back.
- Skin Appearance: The skin should be smooth, shiny, and consistent in color. Skip eggplants with any blemishes, bruises, or those that appear dull and/or wrinkled.
- Weight: It should be heavy for its size, which is a sign of it being fresh with lots of moisture.
- Stem and Cap: The stem should appear green and fresh, rather than brown and dried up.
Best Way to Store Eggplants?
Eggplants do not tolerate either heat or cold very well. To keep them as fresh as possible:
- Refrigerate: Keep in the crisper drawer of the refrigerator. To prevent the eggplant from losing moisture, place it in a plastic bag.
- Use Soon: Best when used within 1-2 days of purchasing. Keeping eggplants longer can cause them to become bitter and develop a spongy texture.
Ways to Minimize the Bitterness of Eggplant
Certain compounds present in eggplants can cause them to have a mildly bitter flavor. To minimize the bitterness:
- Salting: Cut the eggplant into your desired shape and salt the pieces.
- Resting: Allow the salted eggplant to rest for around 30 minutes. This will help the salt extract extra moisture and bitterness.
- Rinsing: Under cold water, rinse off the slices to eliminate any remaining salt.
- Drying: Before cooking, pat dry with a paper towel.
This also reduces the amount of oil absorbed during the cooking process.
Frequently Asked Questions
Can You Eat Raw Eggplant?
Eggplant can be consumed raw but is usually cooked. When raw, it has a firm texture and may be slightly bitter. Cooking softens the eggplant, with techniques such as grilling, roasting, or sautéing enhancing its natural sweetness.
Can You Eat Eggplant Skin and Seeds?
Yes, you can eat both the skin and seeds of eggplants. In fact, they offer some nutritional benefits. The skin, in particular, contains the antioxidant nasunin. However, the bigger and more mature an eggplant is, the tougher the skin and the more pronounced the seeds. In such cases, some prefer to peel away the skin and remove the seeds.
Conclusion
Eggplants are a great food choice to incorporate into your diet and come with a variety of health benefits that are all scientifically proven. In addition to a high number of antioxidants, they promote heart health, help with blood sugar regulation, and support digestive health. With all of these benefits, eggplants provide several of the nutrients necessary for adequate health overall.
They are rich in history and significance across cultures and world cuisines. Whether as part of a chunky ratatouille, a spicy baba ganoush, or simply grilled with some herbs and olive oil, eggplants offer the perfect balance of flavor and nutrition.
Like all food, it is crucial to eat eggplants in moderate amounts and be aware of any individual sensitivities or conditions. Consuming them in such a manner, choosing fresh ones, and cooking them adequately will ensure you are reaping all their benefits.