Eriodictyol

Eriodictyol: A Comprehensive Reference

1. Identity: Chemical Name, Structure, and Natural Sources

Chemical Identity

Eriodictyol is a flavanone compound with the systematic chemical name 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-2,3-dihydrochromen-4-one, a molecular weight of 288.25 g/mol, and the molecular formula C₁₅H₁₂O₆. It belongs to the subclass anthoxanthins-flavanone. It is also known in the older chemical literature as (S)-2-(3,4-dihydroxyphenyl)-2,3-dihydro-5,7-dihydroxy-4-benzopyrone, as documented in foundational structural work.

Structurally similar to other flavonoids such as hesperidin and naringenin, eriodictyol is characterized by its phenolic ring system. It consists of three hydroxyl (–OH) groups attached to its phenolic rings, contributing to its antioxidant capacity; these hydroxyl groups are key to its ability to neutralize reactive oxygen species (ROS), preventing oxidative damage at the cellular level.

Primary Botanical Source

Eriodictyol is a bitter-masking flavanone extracted from yerba santa (Eriodictyon californicum), a plant native to North America. This plant has various traditional names, including yerba santa (sacred herb), mountain balm, bear's weed, gum bush, gum plant, and consumptive weed. Eriodictyol was first extracted from Eriodictyon californicum along with three other flavanones. The other three flavanones identified in this plant as having taste-modifying properties are homoeriodictyol, its sodium salt, and sterubin.

Additional Plant Sources

Eriodictyol is widespread in citrus fruits, vegetables, and medicinally important plants. Eriodictyol is also found in Eupatorium arnottianum, its glycosides (eriocitrin) in lemons and Rosa canina, and in the twigs of Millettia duchesnei. It has also been reported to be extracted from the stem bark of Piptadeniastrum africanum, a plant widely used in African traditional remedies. Eriodictyol is commonly found in various edible plants such as tangerines, bitter oranges, lemons, peanuts, loquats, wormwood, oxtails, and rhodiola.

Eriodictyol is naturally abundant in citrus fruits, especially lemons (1.1 mg per 100 g), oranges (1.5 mg per 100 g), limes (0.29 mg per 100 g), and grapefruits (0.59 mg per 100 g); it is present in both the pulp and peel, making whole fruit consumption an excellent way to incorporate this flavonoid into the diet. Other sources include peppers and certain herbs in the mint family, though these contain smaller amounts.

Forms and Preparations

Being a less polar compound, eriodictyol can be extracted from different plant sources with ethyl acetate, acetone, and dichloromethane-based solvents. These organic solvent-based extractions are currently being replaced by modern green extraction methods; supercritical fluid extraction works as an eco-friendly and efficient method to obtain relatively pure bioactives. Ultrasound-assisted extraction and high-performance liquid chromatography (HPLC) are commonly used methods for the separation and analysis of eriodictyol.

Eriodictyol also occurs naturally in glycosidic form. Eriocitrin, the primary glycoside of eriodictyol, can be metabolized into eriodictyol, which then undergoes phase II metabolism such as glucuronidation, sulfation, and methylation, producing hesperetin, homoeriodictyol, eriodictyol-O-glucuronide, and other compounds. As a dietary supplement, eriodictyol is available in standardized extracts, powders, and capsule forms, typically derived from citrus peel or Eriodictyon californicum leaf. Many studies have also shown that some microorganisms can produce eriodictyol as a host, pointing to biosynthetic production routes as well.

2. Traditional and Historical Use

Native American Use of Yerba Santa

The leaves of Eriodictyon californicum, the primary botanical source of eriodictyol, were used in folk formulations for cough, cold, asthma, tuberculosis, lung infection, dry mouth, and muscle spasms. Native Americans used the leaves of this plant to make tea or syrups. The Kawaiisu tribe used tea of yerba santa to treat gonorrhea; the Chumash tribe used its leaves for treating diseases including asthma and pneumonia.

The ethnobotanical history of the American West is rich, with numerous species frequently included in traditional health practices. Historical records offer insight into the traditional use of yerba santa across indigenous tribes in California. The leaves of the native North American plant, Eriodictyon californicum, were once used to mask the bitter taste of pharmaceuticals, an application that continues to be of importance today.

Mexican Folk Medicine

In Mexican folk medicine, yerba santa leaves, rich in eriodictyol, were brewed into teas to soothe mild coughs and clear respiratory conditions. These practices share commonalities with other traditional medical systems that used aromatic, bitter, or astringent plant preparations for respiratory ailments.

Traditional Use of Citrus Peel

In Mediterranean and traditional Chinese recipes, citrus peel was candied or dried into decoctions for coughs, sore throats, and to aid digestion. Citrus peel preparations containing eriodictyol and related flavanones have long featured in culinary and medicinal traditions across Europe and Asia, though eriodictyol was not identified as a discrete compound in those traditions — its isolation and chemical characterization came considerably later.

Historical Scientific Isolation

The story of eriodictyol on the scientific stage began in the early 20th century when chemists isolated flavonoids from citrus peels; but earlier, traditional practitioners had noticed the health effects of citrus and certain herbs rich in bitter and pungent tastes. Scientific attention on eriodictyol really picked up after the 1950s, as chromatography techniques improved.

3. Key Constituents and Established Mechanisms of Action

Antioxidant Mechanisms

Eriodictyol has garnered scientific attention for its strong antioxidant, anti-inflammatory, and neuroprotective properties. At the molecular level, its antioxidant activity operates through multiple routes. Its three hydroxyl groups are key to its ability to neutralize reactive oxygen species (ROS), preventing oxidative damage at the cellular level.

A particularly well-characterized antioxidant mechanism involves the Nrf2 pathway. Eriodictyol induces the nuclear translocation of Nrf2, enhances the expression of HO-1 and NQO-1 (NAD(P)H:quinone oxidoreductase 1), and increases the levels of intracellular glutathione. Eriodictyol stimulates the nuclear protein accumulation of Nrf2 and boosts the expression of superoxide dismutase (SOD), glutathione (GSH), heme oxygenase-1 (HO-1), and catalase (CAT).

Anti-Inflammatory Mechanisms

The anti-inflammatory activity of eriodictyol is closely tied to its regulation of NF-κB signaling. Several studies have indicated that eriodictyol has immunomodulatory effects, including inhibition of nitric oxide (NO) production by blockage of NF-κB activation, as well as mitogen-activated protein kinase (MAPK) phosphorylation in macrophages, and modulation of pro-inflammatory cytokine production through p38 MAPK, extracellular signal-regulated kinase (ERK)-, c-Jun N-terminal kinase (JNK)-, cyclooxygenase-2 (COX-2)-, and CD14-dependent signaling pathways.

Eriodictyol reduces the nuclear levels of NF-κB and the levels of IL-6, malondialdehyde (MDA), and tumor necrosis factor-α (TNF-α). Eriodictyol has been reported to suppress IL-1β-mediated inflammation of chondrocytes by attenuating NF-κB activation, and to downregulate the IL-1β-stimulated overproduction of PGE2, nitric oxide, and COX-2.

Endothelial and Cardioprotective Mechanisms

In human umbilical vein endothelial cells (HUVECs) treated with eriodictyol, upregulation of HO-1 was demonstrated through ERK/Nrf2/antioxidant response element (ARE) signaling pathways. Upregulation of heme oxygenase-1 (HO-1), a phase II detoxifying enzyme, in endothelial cells is considered to be helpful in cardiovascular disease.

Neuroprotective Mechanisms

Eriodictyol provides neuroprotection via its antioxidant nature by activation of the Nrf2/HO-1 cytoprotective pathway; this pathway protects against H₂O₂-induced neurotoxicity in neuron-like cells and amyloid-β in neurons, while also having anti-inflammatory effects involving MAPK and NF-κB pathways. Eriodictyol reduces memory impairment in Alzheimer's disease models by inhibiting ferroptosis; its mechanism is associated with upregulation of the Nrf2/HO-1 pathway mediated by the vitamin D receptor (VDR).

Anticancer Mechanisms

In vitro studies have shown that eriodictyol exerts its anti-inflammatory and antioxidant effects through Akt- and NF-κB-related signaling pathways. Studies consistently report cell-cycle arrest at critical checkpoints, accompanied by activation of both mitochondrial- and death-receptor-mediated apoptotic pathways through disruption of BCL-2 family balance, caspase engagement, and mitochondrial destabilization; eriodictyol also alters intracellular redox dynamics in a dose-dependent manner, selectively sensitizing cancer cells to oxidative and metabolic stress.

Bitter-Masking Mechanism

In screening flavonoids as potential bitter-masking compounds for guaifenesin (a bitter-tasting antitussive drug), eriodictyol, hesperitin, and phyllodulcin were found to be the most potent suitable candidates for bitter-masking activity, verified in a human sensory trial.

Metabolic / Antidiabetic Mechanisms

Eriodictyol has the ability to inhibit α-glucosidase secretions via the OH group of ring B, binding at the C-terminal maltase-glucoamylase GH31 position of the enzyme, providing new insight into functional foods rich in citrus flavonoids for the prevention and treatment of type 2 diabetes. In other studies, eriodictyol was identified as a novel insulin secretagogue through the stimulation of the cAMP/PKA signaling pathway.

Immunomodulatory Mechanisms

Eriodictyol significantly stimulated splenocyte proliferation; however, only B lymphocytes (not T lymphocytes) could be stimulated by eriodictyol in a dose-related manner. Studies assessing the potential effect of eriodictyol on innate immunity reported that eriodictyol significantly enhanced the killing activity of natural killer (NK) cells, T lymphocytes, and macrophages.

4. Scientific Evidence by Area of Use

4.1 Neuroprotection and Neurodegeneration

Eriodictyol, a flavonoid found in citrus fruits, is among the most potent compounds reported to protect human retinal pigment epithelial (RPE) cells from oxidative stress-induced cell death; studies have determined whether eriodictyol-induced phase II protein expression further enhances the resistance of human ARPE-19 cells to oxidative stress. The in vitro study in ARPE-19 cells demonstrated that eriodictyol activates Nrf2 and induces the phase II proteins HO-1, NQO-1, and glutathione. These results raise the question of whether consumption of eriodictyol and/or other bioflavonoids that induce Nrf2 activation and phase II protein expression may, in part, be responsible for some of the ocular benefits associated with specific dietary products identified in epidemiological studies of macular degeneration.

In Alzheimer's disease research, eriodictyol reduces memory impairment in Alzheimer's disease by inhibiting ferroptosis; its mechanism is associated with upregulation of the Nrf2/HO-1 pathway mediated by VDR. The evidence for this comes from a transgenic mouse model (APP/PS1 mice), not human clinical trials. In herbarium-based screening research, the protective properties of Eriodictyon extracts correlated with the amount of sterubin, but not with eriodictyol or homoeriodictyol alone, indicating that sterubin is the major active compound in these species.

For cerebral ischemia, eriodictyol-7-O-glucoside (E7G) ensures protection for cerebral ischemic injury through its Nrf2/ARE pathway; in cultured astrocytes, E7G enhances the nuclear translocation of Nrf2 and triggers the activation of downstream Nrf2/ARE genes, providing antioxidant responses. This evidence is preclinical (cell and animal model data). No controlled human clinical trials examining eriodictyol specifically for neurological outcomes had been published as of the available literature.

Evidence strength: Preclinical only — cell culture and animal model studies. No human clinical trial evidence is available for neurological endpoints.

4.2 Cardiovascular and Endothelial Protection

The pathophysiology of cardiovascular diseases is complex and may involve oxidative stress-related pathways; eriodictyol is a flavonoid present in citrus fruits that demonstrates anti-inflammatory, anti-cancer, neurotrophic, and antioxidant effects in a range of pathophysiological conditions including vascular diseases, and because oxidative stress plays a key role in the pathogenesis of cardiovascular disease, studies have been designed to verify whether eriodictyol has therapeutic potential.

The primary cardiovascular evidence rests on in vitro work using human endothelial cell lines (HUVECs). Human umbilical vein endothelial cells treated with eriodictyol showed upregulation of HO-1 through ERK/Nrf2/ARE signaling pathways. Experimental evidence indicates that eriodictyol controls miRNA and mRNA protein expression in endothelial cells and could potentially be used to treat vascular diseases. These are in vitro findings and have not been confirmed in human cardiovascular trials.

Evidence strength: Primarily in vitro cell-based; limited animal data. No published human cardiovascular clinical trials.

4.3 Anti-Inflammatory and Immunomodulatory Effects

Animal and cell-based studies consistently demonstrate anti-inflammatory activity across multiple organ systems. Eriodictyol suppressed MUC5AC mucin production and gene expression induced by phorbol 12-myristate 13-acetate (PMA) in human pulmonary epithelial NCI-H292 cells via suppression of inhibitory kappa Bα degradation and NF-κB p65 nuclear translocation. In a lipopolysaccharide-mediated acute lung injury mouse model, eriodictyol dramatically reduced the expression levels of IL-6, PGE2, IL-1β, and TNF-α in the bronchoalveolar lavage fluid; the activation of COX-2/NLRP3/NF-κB and Nrf2 signaling was also attenuated by eriodictyol.

Eriodictyol inhibited nitric oxide (NO) production and lysosomal enzyme activity in murine peritoneal macrophages cultured ex vivo, suggesting a potential anti-inflammatory action.

Evidence strength: Moderate preclinical (in vitro and animal model). No human clinical trial data specific to inflammatory endpoints.

4.4 Anticancer Activity

In vitro studies found that eriodictyol has anti-tumor activity in lung, colon, breast, pancreas, and liver cancer, and most significantly in glioma cell lines; eriodictyol dose- and time-dependently suppresses cell proliferation, migration, and invasion in U87MG and CHG-5 glioma cells. Additionally, eriodictyol induces apoptosis in U87MG and CHG-5 cells and downregulates the PI3K/Akt/NF-κB signaling pathway in a concentration-dependent manner.

In lung cancer, eriodictyol showed potential growth-inhibiting activity against human lung A549 cancer cells, exhibiting an IC₅₀ of 50 µM against these cells. In gastric cancer cell lines, efficient inhibition of phosphorylation and activation of PI3K/AKT by eriodictyol was validated, and eriodictyol was identified as the most effective anti-gastric cancer flavonoid in the tested panel.

A 2026 review brings together and critically examines the available evidence on eriodictyol as an emerging anticancer flavanone, integrating findings from cellular experiments, molecular analyses, and animal models to develop a unified perspective on how eriodictyol interferes with signaling programs that sustain malignant behavior.

Evidence strength: All anticancer evidence is preclinical (cell lines and animal models). No human oncology trials have been published.

4.5 Antidiabetic and Metabolic Effects

Research into eriodictyol's potential to address type 2 diabetes has proceeded along two main lines: α-glucosidase inhibition and insulin secretion. Eriodictyol inhibits α-glucosidase via the OH group of ring B, binding at the C-terminal maltase-glucoamylase GH31 position, offering new insight into functional foods rich in citrus flavonoids for the prevention and treatment of type 2 diabetes related to upregulation of α-glucosidase enzyme. In other studies, eriodictyol was identified as a novel insulin secretagogue through the stimulation of the cAMP/PKA signaling pathway.

In a rat model of diabetic nephropathy, the study explored the role of eriodictyol in protecting against diabetic nephropathy induced by streptozotocin in male rats; diabetes was induced in rats by injection of a single dose (65 mg/kg), with eriodictyol administered orally at 20 mg/kg. The administration of eriodictyol did not affect the rats' body weights and fasting glucose and insulin levels but significantly reduced serum levels of cholesterol, triglycerides, LDL-c, and oxidized LDL-c; eriodictyol prevented streptozotocin-induced nephropathy by a hypolipidemic effect and concomitant antioxidant and anti-inflammatory effects mediated by activating the Nrf2/NF-κB/antioxidant axis.

Evidence strength: Preclinical (enzyme inhibition assays and animal models). No human clinical trials for glycemic outcomes.

4.6 Hepatoprotective Effects

Multiple animal studies have examined eriodictyol's capacity to protect the liver from chemical injury. In a study of arsenic trioxide–induced liver injury in rats, eriodictyol inhibited arsenic trioxide-induced ALT and AST production, and these results suggested that eriodictyol exhibits protective effects against arsenic trioxide-induced liver injury. Eriodictyol remarkably suppressed arsenic trioxide-induced MDA and ROS production, and the inhibition of SOD, GPX, and CAT activity by arsenic trioxide was reversed by eriodictyol.

In a 2023 study of LPS/D-galactosamine-induced acute liver injury (ALI), 47 targets were predicted for the treatment of ALI with eriodictyol, and the PI3K/AKT signaling pathway played a key role in its anti-ALI processing; the in vivo experiment showed that eriodictyol can effectively reduce liver function-related biochemical indicators such as ALT, AST, and AKP, and can also upregulate the levels of SOD and GSH, and inhibit the release of IL-1β, IL-6, and TNF-α.

Evidence strength: Animal model data only. No controlled human hepatic studies.

4.7 Respiratory and Mucus-Modulating Effects

Given the traditional use of Eriodictyon californicum for respiratory conditions, laboratory investigation of eriodictyol's effects on airway biology has been undertaken. Studies investigated whether eriodictyol exerts an effect on the production and gene expression of MUC5AC mucin in human pulmonary epithelial NCI-H292 cells; cells pretreated with eriodictyol and then stimulated with PMA showed suppressed MUC5AC mucin production and gene expression via suppression of IκBα degradation and NF-κB p65 nuclear translocation, suggesting that eriodictyol inhibits mucin gene expression and production in human airway epithelial cells via regulation of the NF-κB signaling pathway.

A similar report confirmed that eriodictyol could function as an anti-inflammatory agent by protecting against Staphylococcus aureus–mediated lung injury.

Evidence strength: In vitro (human cell lines) and animal model evidence. Traditional use of the parent plant is well-documented, but clinical trial evidence is absent.

4.8 Skin Protection and Anti-Photoaging

Eriodictyol showed protective effects on skin HaCaT and FEK-4 cells against UVA radiation; after UVA exposures, eriodictyol promotes cell proliferation and reduces ROS generation. Pretreatment with eriodictyol upregulates the expression of TIMP-1 and COL-1 at the transcriptional level in a dose-dependent manner; UVA-induced phosphorylation of JNK, ERK, and p38, leading to increased MMP-1 expression, is significantly reduced; eriodictyol pretreatment significantly suppresses inflammatory cytokines and inhibits the activation of MAPK signaling cascades in skin cells; these results demonstrate that eriodictyol has both potent anti-inflammatory and anti-photoaging effects.

Evidence strength: In vitro cell culture only. No clinical dermatology trials have been published.

4.9 Bitter Masking — Human Sensory Data

This is one of the few areas where eriodictyol has been evaluated in a human sensory context. In screening flavonoids as potential bitter-masking compounds for guaifenesin, a bitter-tasting antitussive drug, eriodictyol, hesperitin, and phyllodulcin were the most potent suitable candidates for bitter-masking activity; this was verified in a human sensory trial. This represents sensory/perceptual human data rather than a clinical health outcomes trial, but it is the most directly human-relevant evidence base for eriodictyol.

Evidence strength: Human sensory trial confirming bitter-masking properties. Regulatory and commercial use as a taste modifier is established.

5. Body Systems and Health Areas of Association

The body systems and health areas with which eriodictyol is associated, based on laboratory evidence, include antioxidant activity, anti-inflammatory effects, anticancer activity, neuroprotection, cardioprotection, antidiabetic and anti-obesity effects, hepatoprotection, and miscellaneous biological activities. More specifically, the systems addressed by published preclinical research include:

• Central Nervous System: Eriodictyol possesses multiple biological activities, such as anti-inflammatory, antioxidant, antiradical, and neuroprotective effects, studied in models of Alzheimer's disease and ischemic injury.
• Cardiovascular System: Eriodictyol demonstrates anti-inflammatory, anti-cancer, neurotrophic, and antioxidant effects in a range of pathophysiological conditions including vascular diseases.
• Hepatic System: The therapeutic properties of eriodictyol include hepatoprotection, studied in models of drug- and toxin-induced liver injury.
• Respiratory System: Modulation of airway mucus production and lung injury, supported by in vitro and animal evidence.
• Metabolic System: α-Glucosidase inhibition and insulin secretion pathways studied in cell and animal models.
• Integumentary System (Skin): Eriodictyol remarkably reduces UVA-mediated ROS generation and protects skin cells from oxidative damage and cell death; eriodictyol pretreatment significantly downregulates UVA-induced MMP-1 expression and lowers inflammatory responses within skin cells.
• Renal System: Eriodictyol prevents streptozotocin-induced nephropathy by a hypolipidemic effect and concomitant antioxidant and anti-inflammatory effects mediated by activating the Nrf2/NF-κB/antioxidant axis.
• Gustatory System: Acts as a bitter-masking agent with confirmed activity in human sensory testing.

6. Dosage Forms and Dosages Reported in Studies

No standardized dosage for human therapeutic use has been established. The dosages below are reported from preclinical and sensory studies as stated in the cited sources.

• Diabetic nephropathy (rat model): Eriodictyol was administered at 20 mg/kg orally in male streptozotocin-diabetic rats.
• Lung cancer cell line (in vitro): Eriodictyol has an IC₅₀ value of 50 µM against human lung cancer A549 cells.
• Endothelial cell protection (in vitro): Cells were treated with eriodictyol at 10 µM in endothelial cell culture experiments.
• Bitter masking (food/pharmaceutical applications): The range cited in patent literature for hydroxyflavanone bitter-masking compounds is from 0.000001% to 10% by weight based on the total weight of a preparation, though these figures span a class of compounds and are not eriodictyol-specific clinical dosage data.
• Eriocitrin (glycoside precursor) in mice: 100 mg·kg⁻¹·d⁻¹ eriocitrin in diet had no appreciable toxic effect on mice.

It bears emphasis that no human clinical trials have established a recommended oral dose of eriodictyol as a dietary supplement for any therapeutic indication. All dosages in the scientific literature pertain to in vitro concentrations or animal study parameters.

7. Bioavailability and Metabolism

Eriodictyol's bioavailability is a recognized challenge shared by many dietary flavonoids. Some phenolic compounds with low bioavailability, including eriodictyol, are fermented into absorbable and bioactive phenolic acids by the colon microbiota. The gut microbiota therefore plays an important role in determining the biological availability of ingested eriodictyol.

Eriocitrin can be metabolized into eriodictyol first, and then undergo phase II metabolism such as glucuronidation, sulfation, and methylation, producing hesperetin, homoeriodictyol, eriodictyol-O-glucuronide, and other compounds; an earlier study identified that eriocitrin can be metabolized to eriodictyol by gut bacteria such as Bacteroides and Bifidobacterium.

Although natural plant-based compounds including flavonoids have numerous pharmacological benefits, their large-scale extraction from natural sources in high-purity and consistent form, bioavailability, targeted delivery to the site of interest, toxicity, and safety are some of the major challenges in medicinal chemistry. Eriodictyol may necessitate the development of strategies to improve its bioavailability by increasing absorption and metabolic stability, as well as its targeted delivery by formulating appropriate microencapsulation, nano-delivery systems, or micro-emulsions.

8. Safety Considerations and Interactions

General Toxicity Profile

Flavonoids are generally considered non-toxic and can hence be used at higher concentrations in research models. For eriodictyol's glycoside precursor, comparing the body weight, liver, and spleen index of mice in the eriocitrin group and the control group showed no observed difference between the groups, indicating that 100 mg·kg⁻¹·d⁻¹ eriocitrin in diet had no appreciable toxic effect on mice.

In liver-protection studies, liver histological sections of control groups and groups receiving eriodictyol alone showed normal liver structures, suggesting no histopathological liver damage from eriodictyol administration in rodents. Importantly, no controlled human safety studies specifically evaluating eriodictyol as a supplement have been published in the peer-reviewed literature as of this writing.

Absence of Human Clinical Safety Data

Further research is crucial to fully understand eriodictyol's toxicity, contraindications, and pharmacological effects. This is an honest characterization of the state of the field: while animal and cell data are reassuring, the absence of systematic human pharmacokinetic and safety studies means that the full safety profile in humans is not yet established.

Drug Interaction Considerations

No specific drug interaction studies for eriodictyol in humans have been published. As a flavonoid that undergoes phase II metabolism (glucuronidation, sulfation, and methylation), as well as gut microbial biotransformation, theoretical interaction potential exists with drugs sharing these metabolic pathways, but no specific interaction data for eriodictyol are available from clinical sources.

Regulatory Status in Food Use

Eriodictyol and its related compounds from Eriodictyon californicum have a history of use as flavor and taste-modifying agents in food and pharmaceutical preparations. In foods and beverages, an extract of Eriodictyon californicum is used as a flavoring agent. The general regulatory framework governing such use in the United States requires that any substance added to food be demonstrated safe under its conditions of intended use, either through the pre-market food additive approval process or via GRAS (Generally Recognized As Safe) status.

9. Research Limitations and Overall Evidence Assessment

The scientific literature on eriodictyol is extensive at the preclinical level. Eriodictyol has been anticipated to explain its method of activity via multiple cellular signaling cascades. However, a critical review of this body of evidence reveals that virtually all pharmacological claims rest on in vitro cell culture experiments or animal models. The one human-validated application is bitter masking in sensory trials. As of the available literature, no randomized controlled trials, dose-finding studies, or pharmacokinetic studies in human subjects have been published for eriodictyol as a dietary supplement or therapeutic agent for any disease condition. The significant role eriodictyol can play in human health has largely been established from clinical trials undertaken in laboratory animals.

Ongoing research brings together and critically examines the available evidence on eriodictyol as an emerging anticancer flavanone, integrating findings from cellular experiments, molecular analyses, and animal models. Translation of these preclinical findings to clinical practice requires controlled human trials that have not yet been conducted.

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