As the seasons change, many of us (up to 49% according to a recent poll![1]) struggle with the symptoms of hay fever, a common allergic reaction triggered by pollen and other airborne allergens. While conventional antihistamines can provide some relief, they are often not without side effects and as such, many people are looking to more natural alternatives to relieve their symptoms. Quercetin and vitamin C are two compounds that have gathered interest in recent years, demonstrating effectiveness in relieving hay fever symptoms when used separately, and even more effectively when used together. Let’s explore in more detail…
Hay fever and conventional management
Hay fever, or allergic rhinitis, is an immune system overreaction to allergens such as pollen, dust mites, or pet dander. Symptoms include sneezing, nasal congestion, itchy eyes, and a runny nose. These reactions occur when the immune system perceives harmless substances as threats, triggering histamine release and inflammation[2]. Managing hay fever effectively requires reducing histamine production, supporting immune function and minimising inflammation. As such, antihistamine medication is usually the first-line approach to management. However, like with all medications, antihistamines can commonly cause side effects, include drowsiness, dry mouth, urinary issues, nausea and headaches[3] – essentially, you could be swapping one list of symptoms for another!
Quercetin for hay fever relief
Quercetin is a naturally-occurring flavonoid found in various fruits, vegetables and herbs, including apples, onions, berries and leafy greens. It is well known for its potent antioxidant and anti-inflammatory properties. One of quercetin’s most valuable functions in allergy relief is its ability to stabilise mast cells, which are responsible for releasing histamine—the compound that triggers sneezing, runny nose and itchy eyes. By inhibiting histamine release, quercetin acts as a natural antihistamine, reducing the severity of allergic reactions.
Quercetin may offer additional health benefits to help support immune system function, including[5]:
- Anti-inflammatory properties: Quercetin may help to lower inflammation by inhibiting inflammatory enzymes and cytokines, which play a role in allergic reactions.
- Immune system modulation: It supports balance within the immune system by reducing overactive immune responses and enhancing defense against pathogens.
- Antiviral and antimicrobial effects: Studies suggest quercetin has properties that help the body fight off viral infections and bacteria[6], making it useful for overall immune health.
While quercetin can be sourced through eating a healthy, balanced diet, the typical dosage used in studies ranges from 500-1000mg per day. Achieving even the lower end of the scale may be challenging through diet alone, and therefore supplementation could prove a more viable option for those looking to benefit from its therapeutic effects in hay fever.
Vitamin C for hay fever relief
Vitamin C is a crucial nutrient with a wide range of health benefits, including immune system support and antioxidant activity[7]. In the context of hay fever relief, as an enzyme cofactor for diamine oxidase (DAO), vitamin C serves as a natural antihistamine by supporting the breakdown of excess histamine in the bloodstream, thereby reducing allergy symptoms[8].
Like quercetin, vitamin C may offer additional health benefits to help support immune system function, including
- Histamine reduction: Studies show that vitamin C decreases blood histamine levels, which helps prevent allergic reactions.
- Anti-Inflammatory properties: As a potent antioxidant, vitamin C neutralises free radicals and reduces inflammation, which can worsen allergy symptoms.
- Immune system support: Vitamin C enhances white blood cell function, helping the body respond more effectively to allergens and infections.
Vitamin C is found in a variety of fruits and vegetables, particularly citrus fruits, bell peppers, strawberries and leafy greens. However, during allergy season, supplementation may be beneficial to ensure adequate levels.
Combining quercetin and vitamin C
While both quercetin and vitamin C offer individual benefits, research demonstrates that their combined use may enhance their potency. Due to its hydrophobic quality, quercetin alone is not well absorbed; it is estimated under 10% of the quercetin consumed is actually utilised by the body[10]. However, vitamin C may enhance the absorption and bioavailability of quercetin, ensuring that the body can utilise it more effectively. Since quercetin is not easily absorbed on its own, vitamin C acts as a carrier, enhancing absorption through the gastrointestinal tract, helping it enter the bloodstream faster and stay active for longer periods.
Moreover, their combined antioxidant effects provide stronger protection against oxidative stress, which can exacerbate allergic reactions. The anti-inflammatory properties of quercetin are amplified by vitamin C, resulting in more significant relief from hay fever symptoms. Together, they work synergistically to reduce histamine levels, strengthen the immune system and lower inflammation[11]. Finally, as an antioxidant, vitamin C can prevent the breakdown (via auto-oxidation) of the quercetin compound to ensure it gets where it needs to go in-tact.
Incorporating quercetin and vitamin C into your routine
To experience the full benefits of quercetin and vitamin C for hay fever relief, you may wish to consider incorporating them into your daily routine through diet or supplementation.
Quercetin is found in a variety of plant-based foods, including apples, onions, citrus fruits, berries, grapes, broccoli and leafy greens. Meanwhile, vitamin C is abundant in oranges, lemons, kiwis, bell peppers, strawberries and tomatoes. Consuming a diet rich in both of these nutrients can help support immune function and reduce allergy symptoms naturally.
For optimal absorption and effectiveness, pairing quercetin-rich foods with vitamin C sources is recommended. For example, a salad with spinach, onions, bell peppers and a citrus-based dressing can provide a powerful combination of both nutrients.
Quercetin supplements are available in various forms, including capsules, powders and liquid extracts, with recommended dosages typically ranging from 500–1000 mg daily. Similarly, vitamin C supplements are available in various, with a daily intake recommendation ranging from 500 mg to 2000 mg. Nutrigold Quercetin Capsules provide 300mg high potency quercetin, derived from a non-citrus plant source, stabilised with the additional antioxidants vitamin C and E, to prevent auto-oxidation.
To conclude, quercetin and vitamin C may offer a natural, effective approach to hay fever relief by reducing histamine release, lowering inflammation, and supporting overall immune function. When used together, they enhance each other’s benefits, providing a more powerful defense against hay fever. Whether through diet or supplementation, incorporating this duo into your daily regimen may help you to enjoy the changing seasons – without hay fever symptoms getting in the way.
[1] Allergy UK (2023) Statistics and figures: Allergy UK: National Charity, Allergy UK | National Charity. Available at: https://www.allergyuk.org/about-allergy/statistics-and-figures/ (Accessed: 13 March 2025)
[2] Bjermer, L. et al. (2019) “The complex pathophysiology of allergic rhinitis: Scientific rationale for the development of an alternative treatment option,” Allergy, Asthma & Clinical Immunology, 15(1). Available at: https://doi.org/10.1186/s13223-018-0314-1.
[3] NHS (2023) Antihistamines, NHS choices. Available at: https://www.nhs.uk/conditions/antihistamines/ (Accessed: 13 February 2025).
[4] Parasuraman, S., Anand David, A. and Arulmoli, R. (2016) ‘Overviews of biological importance of quercetin: A bioactive flavonoid’, Pharmacognosy Reviews, 10(20), p. 84. doi:10.4103/0973-7847.194044
[5] Chirumbolo, S. (2010) “The role of quercetin, flavonols and flavones in modulating inflammatory cell function,” Inflammation & Allergy – Drug Targets, 9(4), pp. 263–285. Available at: https://doi.org/10.2174/187152810793358741.
[6] Qi, Weidong et al. (2022) ‘Quercetin: Its antioxidant mechanism, antibacterial properties and potential application in prevention and control of toxipathy’, Molecules, 27(19), p. 6545. doi:10.3390/molecules27196545.
[7] Moore, A. and Khanna, D. (2023) ‘The role of Vitamin C in human immunity and its treatment potential against COVID-19: A review article’, Cureus [Preprint]. doi:10.7759/cureus.33740.
[8] Jarisch, R. et al. (2011) ‘Influence of orally taken vitamin C on histamine levels and motion sickness’, Journal of Allergy and Clinical Immunology, 127(2). doi:10.1016/j.jaci.2010.12.1040.
[9] Vollbracht, C. et al. (2018) ‘Intravenous vitamin C in the treatment of allergies: An interim subgroup analysis of a long-term observational study’, Journal of International Medical Research, 46(9), pp. 3640–3655. doi:10.1177/0300060518777044.
[10] Kandemir, K. et al. (2022) ‘Recent advances on the improvement of quercetin bioavailability’, Trends in Food Science & Technology, 119, pp. 192–200. doi:10.1016/j.tifs.2021.11.032.
[11] Colunga Biancatelli, R.M. et al. (2020) ‘Quercetin and vitamin C: An experimental, synergistic therapy for the prevention and treatment of SARS-COV-2 related disease (covid-19)’, Frontiers in Immunology, 11. doi:10.3389/fimmu.2020.01451.
