Taxifolin: Effects, Uses and Dosage

What is Taxifolin?

Taxifolin, also known as dihydroquercetin, is a naturally occurring flavonoid belonging to the flavanonol subclass of polyphenols. It is found in a wide variety of plants, including the Siberian larch (Larix sibirica), grapes, onions, and citrus fruits. Over recent years, taxifolin has attracted growing scientific interest due to its broad spectrum of biological activities and potential therapeutic applications.

Sources and Occurrence

Taxifolin is present in numerous plant-based foods and medicinal plants. Key natural sources include:

• Siberian larch (Larix sibirica): one of the richest known sources; high-concentration extracts are produced from the wood
• Grapes and red wine: taxifolin is found especially in the skin and seeds
• Onions: particularly red and yellow varieties
• Citrus fruits: present in the peel of oranges, lemons, and grapefruits
• Milk thistle and other medicinal plants: relevant sources in phytotherapy

Mechanism of Action

Taxifolin exerts its biological effects through several well-described mechanisms:

Antioxidant Activity

Taxifolin is a potent antioxidant. It neutralizes free radicals by donating electrons to reactive oxygen species (ROS), thereby protecting cells and tissues from oxidative stress, which is linked to numerous chronic diseases.

Anti-inflammatory Activity

Taxifolin inhibits several pro-inflammatory signaling pathways, including the activation of the transcription factor NF-κB and the release of cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). These properties make it a subject of interest in inflammatory disease research.

Vascular Protective Activity

Studies indicate that taxifolin can strengthen capillary walls and reduce vascular permeability. It supports collagen biosynthesis and may therefore contribute to overall vascular health.

Antimicrobial and Antiviral Activity

Laboratory studies have demonstrated that taxifolin can be effective against certain bacteria and viruses. The precise mechanisms are still being investigated but appear to involve inhibition of viral replication enzymes and disruption of bacterial cell membranes.

Medical Applications

Taxifolin is being investigated and used across several areas of medicine and nutritional supplementation:

• Cardiovascular health: Due to its antioxidant and vascular-protective properties, it is studied for supporting heart and blood vessel health.
• Neurodegenerative diseases: Preclinical data suggest neuroprotective effects that may be relevant in conditions such as Alzheimer disease and Parkinson disease.
• Liver health: Taxifolin exhibits hepatoprotective properties and may help protect the liver from toxic damage.
• Diabetes: Evidence suggests a blood glucose-lowering effect through inhibition of alpha-glucosidase and improvement of insulin sensitivity.
• Oncology: Laboratory studies show antiproliferative effects against various cancer cell lines; however, robust clinical data remain limited.
• Skin health: As an antioxidant, taxifolin may protect the skin from UV-induced stress and premature aging.

Dosage and Administration

There is currently no single official dosage recommendation for taxifolin. Clinical studies have investigated doses ranging from 100 mg to 600 mg per day. Supplements are commonly available as capsules or tablets. Taking taxifolin with a meal is generally recommended to improve absorption. Individuals with pre-existing health conditions or those taking medications should always consult a healthcare professional before using taxifolin supplements.

Safety and Tolerability

Taxifolin is generally considered safe and well tolerated. No serious adverse effects have been reported in the studies conducted to date. However, the following considerations apply:

• Caution is advised during pregnancy and breastfeeding, as the available evidence is insufficient.
• Taxifolin may theoretically interact with anticoagulant medications such as warfarin; medical consultation is advised.
• Potential interactions with drugs metabolized via the cytochrome P450 enzyme system are possible.
• High-dose or long-term use should be supervised by a healthcare professional.

Scientific Evidence

The evidence base for taxifolin is promising but remains largely in the preclinical and early clinical stages. Numerous in vitro and animal studies confirm its biological activities, but large-scale, randomized clinical trials in humans are still largely lacking. Taxifolin is already approved as a dietary supplement and for certain therapeutic applications in Russia, while in the EU and the USA it is primarily marketed as a food supplement.

References

1. Weidmann, A.E. (2012). Dihydroquercetin: more than just an impurity? European Journal of Pharmacology, 684(1-3), 19-26. PubMed PMID: 22484340.
2. Sagar, S. et al. (2020). Taxifolin: a comprehensive review of its plant sources, chemistry, pharmacological activities and therapeutic significance. RSC Advances, 10, 42539-42563.
3. Croft, K.D. (2016). Dietary polyphenols: antioxidants or not? Archives of Biochemistry and Biophysics, 595, 120-124. PubMed PMID: 27095226.