Eriodictyol - Structure, Food Sources, Supplements, and Health Benefits

by Ani Harutyunyan | Last updated on September 27, 2024

Medically reviewed by Elen Khachatrian

Summary

Eriodictyol is a naturally occurring flavonoid predominantly found in citrus fruits, such as lemons, oranges, and plants like yerba santa. It has drawn significant scientific interest due to its potent antioxidant, anti-inflammatory, and neuroprotective effects. Structurally related to flavonoids like hesperidin and naringenin, eriodictyol functions by neutralizing free radicals and modulating inflammation. This compound offers promising therapeutic potential in the management of neurodegenerative diseases, cardiovascular health, and metabolic conditions such as diabetes.

Although eriodictyol is bioavailable, its effectiveness is limited by rapid metabolism and elimination. Nonetheless, it can be supplemented in capsules and powders and as part of a balanced diet that includes lemons, oranges, and yerba santa. Standard doses in supplements range from 10 to 100 mg per day, though optimal dosage recommendations are not fully established.

Introduction

Eriodictyol is a member of the flavonoid family, a diverse group of polyphenolic compounds found in many plants.

Flavonoids are well-known for their antioxidant and anti-inflammatory properties, which contribute to the prevention of chronic diseases such as cardiovascular disorders, cancer, and neurodegenerative conditions. Among these, eriodictyol is a lesser-known but highly effective compound present in fruits, particularly citrus, and in herbs like Eriodictyon californicum - yerba santa, which has long been used in traditional medicine to treat respiratory conditions (1).

Researchers are increasingly exploring eriodictyol’s potential to alleviate oxidative stress, reduce inflammation, and support brain and heart health. This article will delve deeper into eriodictyol’s structure, metabolism, health benefits, and how it can be incorporated into a health regimen.

Eridictyol Structure and Properties

Eriodictyol is a flavanone, a subclass of flavonoids, with the molecular formula C15H12O6 and a molecular weight of 288.25 g/mol.

It consists of three hydroxyl (–OH) groups attached to its phenolic rings, contributing to its antioxidant capacity (2). These hydroxyl groups are key to its ability to neutralize reactive oxygen species (ROS), preventing oxidative damage at the cellular level.

The unique structure of eriodictyol is crucial to its biological activity. Its rigid, planar molecular conformation allows it to interact with enzymes and proteins involved in cellular defense mechanisms. Like other flavonoids, eriodictyol can donate hydrogen atoms, stabilizing harmful free radicals and preventing lipid peroxidation in cell membranes.

Eriodictyol - Structure

Despite its structural stability in solid form, eriodictyol is sensitive to environmental conditions. It can degrade when exposed to heat, light, or oxygen, reducing its efficacy over time. While moderately soluble in water, it exhibits better solubility in organic solvents, like DMSO, making it useful in various formulations, from supplements to topical creams.

Metabolism

Once ingested, eriodictyol is absorbed through the intestines, where it undergoes extensive metabolism in the liver. In the initial phase (Phase I metabolism), enzymes from the cytochrome P450 family modify the compound through processes like hydroxylation, oxidation, and demethylation. These changes make the molecule more polar and prepare it for the second phase of metabolism (Phase II), where eriodictyol is conjugated with sulfate or glucuronic acid, increasing its solubility for easier excretion through urine (3).

Though eriodictyol is metabolized quickly, limiting its bioavailability, its metabolites may still exert beneficial effects. Studies show that even after metabolic conversion, eriodictyol derivatives retain some ability to combat oxidative stress and inflammation. However, the low bioavailability poses challenges in maximizing its therapeutic potential, prompting ongoing research into delivery systems like nanoparticles and liposomes to improve absorption (4).

Eriodictyol Supplements and Recommended Intakes

Eriodictyol is a dietary supplement often included in formulations targeting cardiovascular and brain health.

Common supplement forms include capsules, tablets, and powders, with dosages ranging from 10 to 100 mg per day (5). Due to its antioxidant and anti-inflammatory effects, it is frequently used in combination with other flavonoids, such as quercetin or hesperidin, to enhance efficacy.

Topical forms of eriodictyol are also becoming more popular, particularly in skin-care products that aim to reduce inflammation, combat oxidative stress, and promote skin repair.

Though there are no established daily intake recommendations for eriodictyol, preliminary research suggests that doses of up to 100 mg are well-tolerated. However, as with any supplement, it is advisable to consult a healthcare professional before supplementation, particularly for individuals taking medication or managing chronic health conditions.

Foods Rich in Eriodictyol

Eriodictyol is naturally abundant in citrus fruits, especially lemons (1.1mg per 100g), oranges (1.5mg per 100g), limes (0.29mg per 100g), and grapefruits (0.59mg per 100g). It is present in both the pulp and peel, making whole fruit consumption an excellent way to incorporate this flavonoid into the diet. Yerba santa (Eriodictyon californicum), a plant traditionally used in Native American medicine, also contains significant amounts of eriodictyol, adding to its therapeutic potential for respiratory conditions.

Other sources include peppers and certain herbs in the mint family, though these contain smaller amounts. Given its presence in such commonly consumed fruits, eriodictyol can easily be integrated into a regular diet through fresh produce, juices, or zest.

Eriodictyol Health Benefits

Antioxidant and Anti-inflammatory Effects

Eriodictyol’s primary health benefits arise from its potent antioxidant activity. As a scavenger of free radicals, it helps fight oxidative stress, which is a key driver of aging and chronic diseases like cancer, cardiovascular disease, and neurodegenerative disorders. By neutralizing ROS, eriodictyol protects cells from DNA damage and preserves cellular function (6).

The compound also possesses anti-inflammatory properties, inhibiting the activity of pro-inflammatory cytokines and enzymes like cyclooxygenase-2 (COX-2) (7). Eriodictyol downregulates the nuclear factor kappa B (NF-κB) pathway, a critical mediator of inflammation, making it beneficial in conditions characterized by chronic inflammation, such as arthritis, cardiovascular disease, and inflammatory bowel disease (8).

Neuroprotection

Research into eriodictyol’s neuroprotective effects is particularly promising. Oxidative stress plays a major role in neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Eriodictyol’s ability to cross the blood-brain barrier enables it to protect neurons from oxidative damage (9).

Preclinical studies have shown that eriodictyol can reduce brain inflammation and modulate neurotransmitter levels, supporting cognitive function. Its neuroprotective actions extend to enhancing synaptic plasticity and reducing amyloid-beta aggregation, a hallmark of Alzheimer’s disease, highlighting its potential in managing cognitive decline and age-related neurodegeneration (10).

Cardiovascular Health

Eriodictyol’s antioxidant and anti-inflammatory properties also contribute to heart health. By scavenging free radicals, the flavonoid helps protect blood vessels from oxidative stress, a key factor in the development of atherosclerosis (11). Its anti-inflammatory effects further reduce endothelial dysfunction, which is the precursor to many cardiovascular diseases (12).

Additionally, eriodictyol promotes vasodilation by stimulating nitric oxide production, helping to relax blood vessels and improve circulation. This effect may help lower blood pressure and reduce the risk of cardiovascular events like heart attacks and strokes. Some studies have also suggested that eriodictyol can inhibit the oxidation of LDL cholesterol, a major contributor to plaque formation in arteries (13).

Anticancer Potential

Emerging research suggests that eriodictyol may have anticancer properties, making it a potential candidate for cancer prevention and therapy. Its antioxidant effects protect cells from mutations caused by oxidative damage, a common pathway in the development of cancer. Additionally, eriodictyol has been shown to inhibit the growth of cancer cells by inducing apoptosis (programmed cell death) and arresting the cell cycle (14).

Studies indicate that eriodictyol affects several signaling pathways involved in cancer progression, such as the PI3K/Akt and MAPK pathways, both of which regulate cell growth and survival. By modulating these pathways, eriodictyol could slow down tumor growth and reduce the likelihood of metastasis. Its potential to inhibit angiogenesis (the formation of new blood vessels in tumors) further supports its role in suppressing cancer development (15).

Skin Health

Eriodictyol is increasingly being recognized for its skin health benefits. Its antioxidant properties help protect the skin from oxidative damage caused by environmental factors like UV radiation and pollution (16). By preventing oxidative stress, eriodictyol can reduce the signs of aging, such as wrinkles and fine lines, while promoting skin elasticity (17).

Moreover, eriodictyol’s anti-inflammatory effects make it useful in treating inflammatory skin conditions like eczema, psoriasis, and acne (18). Its ability to modulate collagen production and inhibit enzymes that degrade elastin adds to its anti-aging potential.

Weight Management and Diabetes

Eriodictyol may also play a role in weight management and diabetes prevention. Animal studies have demonstrated that eriodictyol can inhibit adipogenesis (the formation of fat cells) and enhance lipolysis (the breakdown of fats) (19). Additionally, its antioxidant and anti-inflammatory effects improve insulin sensitivity, making it useful for managing blood sugar levels (20).

By inhibiting α-glucosidase, an enzyme that breaks down carbohydrates into glucose, eriodictyol slows glucose absorption and reduces postprandial blood sugar spikes, making it a promising candidate for managing type 2 diabetes and metabolic syndrome (21).

Health Downsides

While eriodictyol is generally considered safe, high doses could potentially lead to adverse effects. Studies on its cytotoxicity indicate that very high concentrations might harm normal cells, though such effects are unlikely at the doses found in food or supplements (22).

Drug Interactions

Another potential concern is its interaction with medications. As eriodictyol is metabolized by the liver, it may affect cytochrome P450 enzymes, which are responsible for drug metabolism. This could alter drug effectiveness or toxicity. People taking medications should consult a healthcare provider before supplementing with eriodictyol (23).

References

Author name: Ani Harutyunyan

Education: General Medicine at YSMU

Last updated: September 27, 2024

Medically reviewed by Elen Khachatrian