Flavonoids are a diverse group of plant-derived polyphenolic compounds found in fruits, vegetables, and certain medicinal plants. Their use in supporting the venous system, particularly in the treatment of chronic venous insufficiency (CVI), varicose veins, and hemorrhoids, is supported by a significant body of scientific literature. Numerous clinical trials and meta-analyses have shown that flavonoid mixtures—especially micronized purified flavonoid fraction (MPFF), which contains diosmin and hesperidin—can reduce symptoms such as leg swelling, pain, heaviness, and lower leg ulcers associated with venous insufficiency.

The mechanism of action appears to involve flavonoids’ ability to inhibit capillary permeability, improve lymphatic drainage, enhance venous tone, and reduce inflammation. A 2018 Cochrane review and several randomized controlled trials have found moderate to strong evidence that MPFF and related flavonoid supplements are more effective than placebo for reducing symptoms and improving quality of life in patients with CVI. Flavonoids are also included in clinical guidelines for the management of venous disorders in many European countries.

While not all flavonoids or mixtures are equally studied, the clinical efficacy of specific flavonoid preparations for venous support is well-documented, justifying their use beyond traditional practices and earning them a scientific endorsement.