Perilla leaves (Perilla frutescens), known as shiso in Japan or kkaennip in Korea, are aromatic herbs from the mint family. They have long been staples in East Asian cuisine and traditional medicine. These heart-shaped leaves, which can be green or purple, offer a unique flavor often described as a mix of mint, anise, and basil. Modern research supports the plant’s reputation as a health-promoting food by identifying a rich profile of nutrients and specialized plant compounds.
Essential Nutrient Content
Perilla leaves contribute meaningful quantities of macro and micronutrients to the diet. They are a significant source of dietary fiber, providing approximately 5.7 grams per 100 grams of raw leaves. This high fiber content, combined with a low calorie count, supports digestive health and satiety, making them a nutrient-dense addition to meals.
The mineral profile is particularly noteworthy, containing substantial amounts of calcium, iron, and potassium. Calcium content is high, at about 296 milligrams per 100 grams, supporting bone structure and nerve function. Iron is needed for oxygen transport, while potassium regulates fluid balance and blood pressure. The leaves also contain Vitamin A (beta-carotene), Vitamin C, and B-vitamins, all of which support immune defense and metabolic processes.
Unique Bioactive Components and Health Effects
The significant health benefits of perilla leaves stem largely from specialized compounds known as polyphenols and flavonoids. These compounds support the body’s internal balance and defense systems through several mechanisms. The two most studied components are the phenolic acid, rosmarinic acid, and the flavonoid, luteolin.
Rosmarinic acid and luteolin are highly effective antioxidants that neutralize free radicals causing oxidative stress. Oxidative stress is implicated in cellular damage and the progression of many chronic diseases. This scavenging activity helps protect cells from environmental and metabolic wear. This protective mechanism also extends to neuroprotective effects, as luteolin can attenuate the generation of reactive oxygen species that damage neuronal cells.
Beyond antioxidant action, these compounds exhibit potent anti-inflammatory properties by modulating specific signaling pathways. Research indicates that perilla extracts inhibit the activity of inflammatory regulators like nuclear factor kappa B (NF-κB). Rosmarinic acid also inhibits tumor necrosis factor-alpha (TNF-α), a protein central to systemic inflammation. This modulation of the inflammatory cascade is thought to be the basis for the herb’s traditional therapeutic uses.
Perilla compounds have also been studied for their potential to mitigate allergic responses, a property traditionally recognized in East Asian medicine. Rosmarinic acid shows an anti-allergic effect by stabilizing mast cells and reducing the release of histamine. Specific flavonoids may inhibit IgE-mediated histamine release from immune cells, the primary mechanism of immediate-type allergic reactions. Clinical studies using extracts rich in rosmarinic acid have shown positive results in alleviating symptoms of seasonal allergic rhinoconjunctivitis.
Emerging evidence links perilla compounds to supporting cognitive function and brain health. The leaves contain alpha-linolenic acid (ALA), a plant-based omega-3 fatty acid, which is incorporated into brain cell membranes and contributes to neural signaling. The anti-inflammatory and antioxidant actions of luteolin and rosmarinic acid further support brain wellness by protecting neurons from damage.
Safe Consumption and Potential Side Effects
Incorporating perilla leaves into the diet is generally considered safe when consumed as a fresh herb or vegetable. They are widely used in Korean cuisine as a wrap for grilled meats (ssam) and as a flavoring agent in pickles and stews. In Japanese cuisine, they serve as a garnish or accompaniment to seafood.
A primary safety consideration involves perilla ketone, a compound present in the plant’s essential oil. Perilla ketone is a known lung toxin to grazing animals, such as cattle and horses, and can cause pulmonary edema. While the concentration in fresh culinary leaves is typically low enough not to pose a risk to humans, caution should be exercised with highly concentrated essential oils or extracts.
Individuals taking blood-thinning medications, such as Vitamin K Antagonists (VKAs) like warfarin, should be mindful of perilla consumption. Perilla contains Vitamin K, which plays a role in blood clotting and can counteract the effects of these medications. Maintaining a consistent daily intake of Vitamin K is important to ensure the medication remains effective. Due to a lack of sufficient safety data, pregnant or breastfeeding individuals should avoid perilla extracts or supplements.