# Nasturtium (Tropaeolum majus)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/nasturtium
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-31
**Evidence Score:** 2 / 10
**Category:** Other
**Also Known As:** Garden nasturtium, Indian cress, Monk's cress, Nasturtium flower, Capuchin cress, Tropaeolum, Edible nasturtium, Climbing nasturtium, Nasturtio, Capuchina

## Overview

Nasturtium (Tropaeolum majus) is a flowering plant rich in glucosinolates — particularly glucotropaeolin — which are hydrolyzed to benzyl isothiocyanate (BITC), a compound with demonstrated [antimicrobial](/ingredients/condition/immune-support), [antioxidant](/ingredients/condition/antioxidant), and antiproliferative activity. Its high phenolic content, including flavonoids and hydroxycinnamic acids, further contributes to its broad biological effects observed in preliminary research.

## Health Benefits

["\u2022 May possess antiproliferative properties, based on preliminary in vitro evidence where its essential oil demonstrated activity (IC\u2085\u2080<5 \u00b5g/mL) against three human cancer cell lines [3].", "\u2022 Provides high [antioxidant](/ingredients/condition/antioxidant) capacity, attributed to its rich phenolic content, including flavonoids and anthocyanins. In vitro analysis showed red flowers possess the highest radical-scavenging activity [4].", "\u2022 Exhibits potential antibacterial activity, as documented in early studies on nasturtium herb juice; however, specific bacterial targets and outcomes were not detailed in the available research [2].", "\u2022 Serves as a natural source of benzyl isothiocyanate (BITC), a bioactive compound identified in lab studies as a key driver of its potential biological effects [2, 3].", "\u2022 Contains a variety of nutrients, including B vitamins, minerals like potassium and iron, and carotenoids, as noted in analyses of the plant's traditional use profile [2]."]

## Mechanism of Action

Glucotropaeolin, nasturtium's primary glucosinolate, is hydrolyzed by the enzyme myrosinase upon plant tissue damage to yield benzyl isothiocyanate (BITC), which disrupts microbial cell membranes and inhibits bacterial efflux pumps. BITC also modulates apoptotic pathways in cancer cells, likely through caspase activation and inhibition of the [NF-κB](/ingredients/condition/inflammation) signaling cascade, contributing to the antiproliferative IC₅₀ values below 5 µg/mL seen in vitro. Additionally, nasturtium's flavonoids — including quercetin and kaempferol glycosides — scavenge [reactive oxygen species](/ingredients/condition/antioxidant) (ROS) and inhibit lipid peroxidation by donating hydrogen atoms to free radicals.

## Clinical Summary

Most evidence for nasturtium's benefits comes from in vitro and animal studies rather than controlled human clinical trials, limiting the strength of conclusions. In vitro studies have demonstrated antiproliferative activity of nasturtium essential oil (IC₅₀ <5 µg/mL) against three human cancer cell lines and strong [antioxidant](/ingredients/condition/antioxidant) capacity assessed via DPPH and FRAP assays. [Antimicrobial](/ingredients/condition/immune-support) studies show BITC and nasturtium extracts inhibit gram-positive and gram-negative bacteria, including some antibiotic-resistant strains, though human pharmacokinetic and efficacy data remain scarce. The overall evidence is preliminary and promising, but randomized controlled trials in humans are needed before therapeutic claims can be substantiated.

## Nutritional Profile

Nasturtium (Tropaeolum majus) leaves and flowers are nutrient-dense edible botanicals. Macronutrient composition per 100g fresh weight is modest in calories (~30-40 kcal), with low protein (~2-3g), minimal fat (~0.5g), and low carbohydrates (~5-6g), with dietary fiber estimated at ~1-2g. Micronutrient profile is notable for Vitamin C (ascorbic acid): leaves contain approximately 130mg/100g, significantly exceeding many common vegetables and rivaling citrus fruits; Vitamin A precursors (beta-carotene and other carotenoids) are present in moderate amounts, contributing to the orange-yellow pigmentation of flowers; Iron: approximately 1.5-2mg/100g in leaves; Potassium: estimated 300-400mg/100g; Calcium: approximately 100mg/100g; Magnesium: moderate amounts (~20-30mg/100g). Bioactive compounds are a primary point of interest: Glucosinolates, particularly glucotropaeolin (benzyl glucosinolate), are the signature phytochemicals, present at concentrations of 10-30 µmol/g dry weight in seeds, with lower concentrations in leaves; upon enzymatic hydrolysis by myrosinase (activated upon tissue damage or chewing), glucotropaeolin yields benzyl isothiocyanate (BITC), a bioactive compound with demonstrated [antimicrobial](/ingredients/condition/immune-support) and antiproliferative properties. Phenolic compounds include flavonoids (quercetin, kaempferol, and isorhamnetin glycosides) and anthocyanins (particularly in red/orange flowers, including pelargonidin and cyanidin derivatives), with total phenolic content reported at 15-50mg GAE/g dry weight depending on flower color, with red varieties exhibiting the highest concentrations. Carotenoids include lutein, zeaxanthin, and beta-carotene in leaves and flowers. Essential oil constituents include benzyl isothiocyanate as the dominant volatile compound. Bioavailability notes: Vitamin C bioavailability is considered good when consumed fresh and uncooked, as heat degrades ascorbic acid; glucosinolate hydrolysis to active BITC is dependent on intact myrosinase activity, which is reduced by cooking; fat-soluble carotenoids exhibit enhanced bioavailability when consumed with dietary fat; the phenolic compounds may have variable bioavailability depending on [gut microbiome](/ingredients/condition/gut-health) composition and food matrix interactions.

## Dosage & Preparation

No clinically studied dosage ranges for human use have been established, as the research focuses on chemical characterization rather than human trials. Studied preparations have quantified bioactive compounds, such as 27.49 μmol/g of glucosinolates in fresh material, but these are not dosage recommendations [1]. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Nasturtium is generally regarded as safe when consumed in culinary amounts, but high-dose supplemental use may cause gastrointestinal irritation, including nausea and diarrhea, due to its pungent isothiocyanate content. Because glucosinolate metabolites can be goitrogenic at high chronic doses, individuals with [thyroid](/ingredients/condition/hormonal) disorders or those taking thyroid medications such as levothyroxine should exercise caution. Nasturtium may theoretically potentiate the effects of anticoagulant drugs like warfarin due to its vitamin K and flavonoid content, warranting monitoring of INR in affected patients. Pregnant and breastfeeding women should avoid supplemental doses beyond normal food use, as isothiocyanates have shown embryotoxic potential in animal models at elevated concentrations.

## Scientific Research

The available research dossier contains no human clinical trials, randomized controlled trials (RCTs), or meta-analyses with PMIDs. The current scientific evidence is limited to in vitro (cell-based) and chemical characterization studies, which have not yet been validated in human subjects [2, 3].

## Historical & Cultural Context

Nasturtium has a long history in traditional medicine, where it was used as an antiscorbutic (vitamin C source), [antimicrobial](/ingredients/condition/immune-support), and general tonic [2]. It was employed for conditions ranging from the common cold to sclerosis, though the specific traditional systems are not detailed in the provided research [2].

## Synergistic Combinations

Broccoli Sprout Extract, Vitamin C, Green Tea Extract

## Frequently Asked Questions

### What is benzyl isothiocyanate in nasturtium and why does it matter?

Benzyl isothiocyanate (BITC) is the principal bioactive compound produced when nasturtium's glucosinolate, glucotropaeolin, is broken down by the enzyme myrosinase upon chewing or crushing the plant. BITC has demonstrated antimicrobial activity against pathogens including Staphylococcus aureus and E. coli, as well as antiproliferative effects in human cancer cell lines at concentrations below 5 µg/mL in vitro. It is this compound that gives nasturtium its characteristic peppery taste and most of its documented pharmacological properties.

### Can nasturtium help fight bacterial infections?

Preliminary laboratory evidence shows that nasturtium extracts and isolated BITC inhibit the growth of both gram-positive and gram-negative bacteria, including some strains resistant to conventional antibiotics. The mechanism involves disruption of bacterial cell membranes and inhibition of efflux pumps that bacteria use to expel antibiotic drugs. However, these findings are from in vitro studies and have not yet been confirmed in human clinical trials, so nasturtium should not replace prescribed antibiotic therapy.

### Is nasturtium safe to take as a supplement during pregnancy?

Nasturtium in normal dietary amounts — such as adding leaves and flowers to salads — is considered safe during pregnancy, but supplemental or concentrated extracts are not recommended. Animal studies have identified embryotoxic effects at elevated doses of isothiocyanates like BITC, raising concerns about fetal safety. Until human safety data are available, pregnant women should avoid nasturtium supplements and consult a healthcare provider before use.

### Does nasturtium have antioxidant properties and what compounds are responsible?

Yes, nasturtium demonstrates high antioxidant capacity in laboratory assays such as DPPH radical scavenging and FRAP (ferric reducing antioxidant power), primarily attributed to its rich phenolic profile. Key contributors include flavonoids — particularly quercetin and kaempferol glycosides — as well as hydroxycinnamic acids and vitamin C found abundantly in the plant's leaves and flowers. These compounds neutralize reactive oxygen species (ROS) by donating hydrogen atoms, thereby reducing oxidative stress at the cellular level.

### How much nasturtium should you take daily for health benefits?

There is currently no established standardized therapeutic dosage for nasturtium supplements because robust human clinical trials defining effective and safe dose ranges have not yet been conducted. Traditional and culinary use involves consuming fresh leaves and flowers — typically a handful (roughly 20–50 g) added to foods — which delivers modest amounts of glucosinolates and antioxidants without significant risk. Anyone considering higher-dose extracts or capsules should consult a healthcare provider, particularly if they have thyroid conditions or are taking anticoagulant medications.

### What forms of nasturtium supplement are available and which is most effective?

Nasturtium is available as dried flower/leaf preparations, essential oil extracts, and standardized phenolic extracts, with each form varying in concentration of active compounds like benzyl isothiocyanate and flavonoids. Essential oil extracts and standardized phenolic preparations tend to offer higher bioavailability of the active phytochemicals compared to whole dried herb forms. The choice depends on intended use, as essential oils are more potent for antimicrobial applications while whole herb preparations provide broader nutrient profiles including vitamins and minerals.

### Does nasturtium interact with common medications or blood thinners?

Limited clinical data exists on nasturtium's interactions with medications, though its antimicrobial and anti-inflammatory properties suggest potential interactions with immune-modulating drugs or antibiotics when used concurrently. Individuals taking anticoagulant medications should consult healthcare providers before supplementing, as some preliminary evidence suggests nasturtium may have mild antiplatelet activity. More research is needed to establish definitive interaction profiles with specific drug classes.

### What does current clinical research show about nasturtium's antiproliferative potential against cancer cells?

Preliminary in vitro studies demonstrate that nasturtium essential oil exhibits activity against human cancer cell lines with IC₈₀ values below 5 µg/mL, suggesting potential antiproliferative effects at relatively low concentrations. However, these findings are limited to laboratory cell culture studies and have not yet been validated in animal models or clinical trials in humans. Significantly more research is needed before nasturtium can be recommended as a cancer-preventive agent, and existing claims should be viewed as exploratory rather than evidence-based.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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