Grapefruit (Citrus paradisi)

Table of Contents

Other names

Grapefruit Peel
Grapefruit Extract
Citrus paradisi

Synopsis

Grapefruit (Citrus × paradisi) is a hybrid citrus fruit developed from pummelo (Citrus maxima) and sweet orange (Citrus sinensis), first documented in Barbados in the 18th century. It is now cultivated globally and valued for its tart-sweet flavor, hydrating juice, and dense nutrient profile. Grapefruit is rich in vitamin C, potassium, fiber, and bioactive phytochemicals such as naringin, limonoids, hesperidin, and lycopene (in pink varieties). These compounds provide potent antioxidant, anti-inflammatory, immune-modulating, and lipid-lowering effects.

In modern health and nutrition, grapefruit is used to support immune function, improve skin health, reduce oxidative stress, and aid digestion. Its high flavonoid content—especially naringin and narirutin—contributes to cholesterol regulation, vascular support, and detoxification. Grapefruit also promotes appetite regulation and is often included in weight loss and cleansing regimens.

However, grapefruit is also known for its ability to interact with certain medications, particularly those metabolized by cytochrome P450 enzymes (CYP3A4). Compounds in grapefruit can inhibit drug metabolism, leading to increased concentrations of medications such as statins, calcium channel blockers, and certain immunosuppressants—making caution necessary in clinical settings.

Historical Use
Grapefruit’s use as a medicinal fruit began more recently than other citrus species, but it was quickly integrated into Western herbal and nutritional traditions after its discovery in the 18th century. By the 19th and 20th centuries, it was praised for its cleansing, purifying, and energizing properties, especially in fasting and detox diets. It was promoted as a “health tonic” in early natural hygiene movements and became popular in American wellness culture for weight management and liver support.

In folk remedies, grapefruit juice was used to stimulate digestion, cleanse the liver, and reduce fevers, while the peel and essential oil were applied for antiseptic and lymphatic-stimulating purposes. The seeds and seed extract (grapefruit seed extract, or GSE) have been used more recently as natural antimicrobials, with purported effects against bacteria, fungi, and viruses.

Today, grapefruit continues to be a staple in functional nutrition, immune support, and detox protocols, especially in the form of whole fruit, juice, seed extract, and essential oil. Its bright, invigorating profile bridges culinary enjoyment and therapeutic application, though its drug interactions remind us of the need to balance natural remedies with pharmaceutical awareness.

Uses: Health Conditions

None

Body Systems

Digestive System (Science)
Immune System (Science)
Liver (Science)
Mitochondria (Science)