# Amaranthus cruentus (Red Amaranth)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/amaranthus-cruentus
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-29
**Evidence Score:** 2 / 10
**Category:** Vegetable
**Also Known As:** Red amaranth, Purple amaranth, Blood amaranth, Mexican grain amaranth, Amaranto rojo, Bledo colorado, Quintonil rojo, African spinach (regional), Callaloo amaranth

## Overview

Amaranthus cruentus, or red amaranth, is a dark leafy green rich in betacyanins (40.42 mg/100g dry weight) and phenolic compounds that neutralize free radicals through electron donation and metal ion chelation. Its [antioxidant activity](/ingredients/condition/antioxidant), measured at IC₅₀ values of 56–423 µg/mL, positions it as a functional food candidate, though human clinical evidence remains limited.

## Health Benefits

• [Antioxidant activity](/ingredients/condition/antioxidant): Contains phenolic compounds with free-radical scavenging activity (IC₅₀ 56-423 µg/mL) and iron-reducing power of 2.26-2.56 mmol ascorbic acid equivalent/gram (preliminary evidence from in-vitro studies)
• Rich phytochemical profile: Provides betacyanins (40.42 mg/100g dry weight), flavonoids (0.37-7.06 mg/100mg extract), and tannins (2.83-10.17 mg/100mg extract) (compositional analysis only)
• Nutrient density: Classified as USDA nutrient-dense food with high concentrations of calcium, potassium, and magnesium (based on compositional data)
• Diverse bioactive compounds: Contains polyphenols, steroids, terpenoids, saponins, and betalains extracted optimally with hydroacetonic solvents (phytochemical characterization study)
• Potential metabolic support: In animal models, demonstrates ability to modulate fermentation and reduce methane production (preliminary animal evidence only)

## Mechanism of Action

Betacyanins in Amaranthus cruentus donate hydrogen atoms to [reactive oxygen species](/ingredients/condition/antioxidant), interrupting lipid peroxidation chain reactions and reducing ferric ions (Fe³⁺) to ferrous ions (Fe²⁺) at a rate of 2.26–2.56 mmol ascorbic acid equivalent per gram, reflecting significant iron-reducing capacity. Phenolic compounds including rutin and quercetin derivatives inhibit pro-[inflammatory](/ingredients/condition/inflammation) enzymes such as cyclooxygenase (COX) and lipoxygenase (LOX) by competing at their active sites. Additionally, betacyanins may upregulate endogenous antioxidant enzymes including superoxide dismutase (SOD) and catalase via Nrf2 pathway activation, though this mechanism is currently supported only by in-vitro and animal data.

## Clinical Summary

Current evidence for Amaranthus cruentus is primarily derived from in-vitro assays and preliminary phytochemical analyses, with no large-scale randomized controlled trials in humans published to date. In-vitro studies using DPPH and FRAP assays have quantified free-radical scavenging at IC₅₀ values ranging from 56 to 423 µg/mL depending on extraction solvent and plant part tested. Animal studies have suggested [anti-inflammatory](/ingredients/condition/inflammation) and [hepatoprotective](/ingredients/condition/detox) effects at doses of 200–400 mg/kg body weight, but direct extrapolation to human dosing remains speculative. The overall evidence quality is low-to-preliminary, and health claims beyond nutritional value require validation through well-designed human trials.

## Nutritional Profile

Red Amaranth (Amaranthus cruentus) leaves and seeds provide a dense nutritional profile. Macronutrients (per 100g fresh leaves): protein 2.5–3.5g (notably high for a leafy vegetable, containing essential amino acids including lysine at ~5.3g/100g protein — superior to most cereals); carbohydrates 4.0–5.5g; dietary fiber 2.0–3.2g; fat 0.3–0.5g; moisture 85–90g. Seeds are more calorie-dense: protein 13–18g/100g dry weight, fat 6–8g (rich in unsaturated fatty acids, ~77% linoleic and oleic acids), starch 50–60g, and squalene (~5–8% of seed oil, a bioactive triterpene). Micronutrients (per 100g fresh leaves): calcium 267–415mg (among the highest of leafy vegetables, though bioavailability is reduced ~50–70% due to oxalic acid content of 700–870mg/100g forming insoluble calcium oxalate); iron 3.0–4.6mg (non-heme; absorption enhanced by co-consumed vitamin C); magnesium 55–75mg; potassium 340–480mg; phosphorus 50–70mg; zinc 0.9–1.2mg. Vitamins: vitamin C 43–80mg/100g fresh weight (heat-labile; significantly reduced by boiling); beta-carotene (provitamin A) 1.5–4.0mg/100g (fat-soluble; bioavailability improved with dietary fat); folate 85–120µg/100g; vitamin K approximately 300–400µg/100g (clinically relevant for anticoagulant drug interactions). Bioactive compounds: betacyanins (red pigments, primarily amaranthine) at 40.42mg/100g dry weight contributing [antioxidant](/ingredients/condition/antioxidant) capacity; flavonoids 0.37–7.06mg/100mg extract (including rutin and quercetin derivatives); tannins 2.83–10.17mg/100mg extract (may reduce protein and mineral bioavailability at high intakes); phenolic acids including gallic and caffeic acid derivatives. Antinutrients: oxalates (~870mg/100g fresh), phytates (0.4–0.9g/100g dry seed), and tannins collectively reduce mineral bioavailability; blanching or boiling reduces oxalate content by 30–60% and phytates by ~40%, improving net mineral absorption.

## Dosage & Preparation

No clinically studied dosage ranges for human consumption are available from the current research. The studies provided only address phytochemical extraction methods and animal feed supplementation levels, which are not applicable to human dosing recommendations. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Amaranthus cruentus is generally recognized as safe when consumed as a food, but concentrated extracts have not been evaluated in formal human toxicity trials. Its notable oxalate content (comparable to other amaranth species) may increase kidney stone risk in individuals with calcium-oxalate nephrolithiasis or impaired renal function. The plant's iron-reducing compounds may theoretically interact with iron-chelation therapies or alter the absorption of co-administered minerals such as zinc and calcium. Pregnant and breastfeeding women should limit use to culinary amounts, as pharmacological doses lack safety data in these populations.

## Scientific Research

The current research on red amaranth consists primarily of phytochemical characterization studies and animal feed applications. No human clinical trials, randomized controlled trials, or meta-analyses were available in the provided research. The existing studies focus on compositional analysis of bioactive compounds and [antioxidant activity](/ingredients/condition/antioxidant) through in-vitro methods.

## Historical & Cultural Context

Traditional use information for red amaranth in historical medicine systems was not included in the provided research. The available studies focus exclusively on modern phytochemical analysis and agricultural applications.

## Synergistic Combinations

Other dark leafy greens, vitamin C sources, iron-rich foods, [antioxidant](/ingredients/condition/antioxidant)-rich berries, quercetin supplements

## Frequently Asked Questions

### What is the main antioxidant compound in red amaranth?

The primary antioxidant compounds in Amaranthus cruentus are betacyanins, present at approximately 40.42 mg/100g dry weight, alongside phenolic acids and flavonoids such as rutin and quercetin derivatives. Betacyanins donate hydrogen atoms to free radicals and reduce ferric ions, achieving an iron-reducing power of 2.26–2.56 mmol ascorbic acid equivalent per gram. These values are measured in laboratory assays and may not fully translate to in-vivo bioavailability.

### How does red amaranth compare to spinach as an antioxidant source?

Red amaranth contains betacyanins, a pigment class absent in spinach, which provide a distinct antioxidant mechanism via nitrogen-containing chromophores in addition to shared phenolic compounds. Spinach is better studied for its lutein and zeaxanthin content (approximately 12 mg/100g), whereas red amaranth's betacyanin content of ~40 mg/100g dry weight gives it a different phytochemical profile. Direct head-to-head human bioavailability trials comparing the two greens have not been published, so ranking their overall antioxidant efficacy in vivo remains premature.

### Can red amaranth help with inflammation?

Preliminary in-vitro and animal studies suggest Amaranthus cruentus extracts inhibit pro-inflammatory enzymes COX and LOX and reduce markers such as TNF-α and IL-6 at doses of 200–400 mg/kg in rodent models. The phenolic compounds rutin and quercetin derivatives are the most likely mediators, acting through competitive inhibition at enzyme active sites. No human clinical trials have confirmed an anti-inflammatory effect at any specific dose, so this benefit remains investigational.

### Is red amaranth safe to eat every day?

As a whole food, red amaranth leaves are safe for daily consumption for most healthy adults and provide iron, calcium, vitamin C, and protein alongside its phytonutrients. However, its moderate oxalate content means individuals with a history of calcium-oxalate kidney stones should limit intake to 2–3 servings per week and ensure adequate hydration. Concentrated supplement forms lack long-term human safety data, and daily use at pharmacological doses is not currently supported by evidence.

### What is the IC₅₀ value of red amaranth and what does it mean?

The IC₅₀ of red amaranth extracts in DPPH free-radical scavenging assays ranges from 56 to 423 µg/mL, meaning that 56–423 micrograms of extract per milliliter are required to neutralize 50% of the free radicals in the test solution. Lower IC₅₀ values indicate stronger antioxidant potency; the wide range reflects differences in extraction solvent, plant part (leaf vs. stem vs. seed), and drying method. These are in-vitro measurements and do not directly predict antioxidant activity in human tissues after digestion and metabolism.

### What are betacyanins and why are they important in red amaranth?

Betacyanins are water-soluble pigments responsible for red amaranth's deep color and are distinct from anthocyanins found in other red plants. Red amaranth contains approximately 40.42 mg of betacyanins per 100g of dry weight, making it a concentrated source of these compounds. Betacyanins possess antioxidant and anti-inflammatory properties and may contribute to the plant's overall health-promoting effects beyond its phenolic content.

### How does cooking or processing affect the antioxidant compounds in red amaranth?

Heat exposure during cooking can degrade some heat-sensitive phytochemicals like flavonoids and betacyanins, though the extent depends on cooking method and duration. Raw or lightly steamed red amaranth typically retains higher levels of its phytochemical profile compared to prolonged boiling or high-temperature processing. To maximize antioxidant intake, minimal-heat preparation methods such as light steaming or consuming it in salads are generally recommended.

### Is red amaranth bioavailable in its whole-food form compared to extract supplements?

While whole red amaranth provides its phytochemicals in a complex food matrix with fiber and other nutrients that may enhance absorption, isolated extracts show measurable antioxidant activity in laboratory settings (IC₅₀ values of 56-423 µg/mL). The bioavailability of betacyanins and flavonoids from whole food sources may be superior due to synergistic interactions with other plant compounds, though direct human absorption studies comparing forms are limited. Consuming red amaranth as a whole food rather than relying solely on extracts ensures intake of the full nutrient profile including minerals and fiber.

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