Citrus bioflavonoids, a group of polyphenolic compounds found in citrus fruits, have been investigated for their potential to support mucus membranes, which include the linings of the respiratory, digestive, and urogenital tracts. Scientific evidence for their use in this context is moderate and largely based on their antioxidant, anti-inflammatory, and capillary-strengthening properties.

Several studies have shown that bioflavonoids, especially hesperidin and rutin, can reduce inflammation and oxidative stress in epithelial tissues. These actions are thought to protect and stabilize the integrity of mucus membranes. For example, bioflavonoids may inhibit the activity of enzymes that degrade connective tissue and may reduce the permeability of capillaries, helping to maintain proper tissue hydration and barrier function. Some clinical and preclinical studies suggest benefits in conditions such as chronic sinusitis, allergic rhinitis, and oral mucositis, where mucus membrane integrity is compromised.

However, most of the evidence comes from animal studies, small clinical trials, or studies with mixed formulations (often including vitamin C), making it difficult to attribute effects specifically to citrus bioflavonoids. While there is a plausible mechanism and some supportive evidence, more robust, large-scale human trials are needed to confirm these benefits. Thus, the use of citrus bioflavonoids to support mucus membranes is scientifically plausible, with moderate evidence but not yet definitive proof.