Eggplant is a nightshade vegetable with wide fruit diversity in shapes, sizes and colours. A very nutritious, low-glycaemic and high fibre vegetable, containing only 35 calories per cup. 1 cup cooked eggplant provides 2.5 grs fibre (particularly pectin), 1 gram protein, 9 grams carbohydrate, vitamin A, C, E, K, folate (B9), niacin (B3), choline, calcium, iron, magnesium, phosphorus, potassium. Eggplant is a typical and versatile vegetable in the Mediterranean and Middle Eastern diets containing amazing powerful antioxidants which help to maintain health and prevention of diseases.
Recent research has classified eggplants among the top ten vegetables with antioxidant capacity due to its high content of phenolic phytochemicals in its flesh, and the anthocyanin nasunin in the peel. Phenolic compounds are produced by the plant during growth, reproduction or as a response to environmental stress conditions, as defense against infection by pathogens and ultraviolet radiation. These compounds have many identified health benefits including antioxidant, anti-inflammatory, anti-aging, and anti-cancer.
Health benefits promoted by phytochemicals in eggplants
Main antioxidant compound found in eggplant peel, an anthocyanin pigment which gives eggplants the characteristic blue and purple colours. Nasunin is a potent antioxidant with documented health benefits:
Slow aging – neutralize free radicals and reduce inflammation which helps maintain integrity of cells, tissues, arteries and slow aging;
Cardioprotective– reduces cholesterol and protects lipids from oxidation, thus reducing the risk of plaque formation in arteries;
Bone health – nasunin’s antioxidant properties exert beneficial effects on bone metabolism, help maintain bone mass, and prevent osteoporosis;
Anti-cancer – shown to protect colon cells from DNA damage and inhibit tumor angiogenesis, the growth of new blood vessels that cancers need to grow.
Phenolic compound with strong antioxidant, anti-inflammatory, analgesic and anti-microbial activities.
Anti-obesity and diabetes – improves lipid metabolism, slows down glucose absorption, and inhibits gluconeogenesis (endogenous production of glucose), therefore improving blood sugar regulation.
Cardioprotective – chlorogenic acid reduces blood pressure and lower LDL cholesterol, reducing risk of cardiovascular disease.
Anti-cancer – selectively promote cancer-cell death, such as in leukaemia and lung cancer.
Adverse effects associated with oxalates
Eggplants contain high levels of oxalic acid which is problematic for people with kidney disease, and those prone to forming kidney stones. These individuals may benefit from avoiding high oxalate foods.
Eggplants can be prepared roasted, grilled, stewed, boiled, steamed, stir-fried or pan-fried. To help reduce the bitterness when pan-frying, the eggplant can be sliced and sprinkled with a generous amount of salt and allowed to sit for 20 minutes in a colander. Then rinse and pat dry with paper towel before cooking. The salt draws moisture and reduce some of the phenolics responsible for the intense bitterness which some varieties of eggplant have when pan-fried.
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