Could Your Diet Be Making Allergies Worse? by Mack Bruce

Diet & Seasonal Allergies

Sneezing, runny nose, itchy eyes, congestion, and headache are hallmark symptoms of seasonal “hay fever,” or allergic rhinitis (AR), one of the most prevalent chronic inflammatory conditions worldwide, affecting ~400 million individuals (2026). In North America, spring pollen exposure typically begins in February and can extend into early summer, with regional variability shaped by tree and grass pollination patterns. Individuals allergic to ragweed often experience symptoms from late summer through fall. Several key features characterize seasonal AR: it arises from complex interactions between the immune system and environmental antigens; common triggers include tree pollen, mold, and ragweed; and exposure to these allergens induces histamine release, which leads to inflammation, fatigue, and other symptoms. According to the American College of Allergy, Asthma & Immunology, pollen thrives when nights are cool and days are warm; molds proliferate in heat and high humidity; pollen levels peak in the morning; rain temporarily suppresses pollen but counts rise after nightfall; and pollen surges on warm, windy days. A cascade beginning in the nasal mucosa with an immunoglobulin E–mediated response triggers symptoms such as nasal itching, sneezing, rhinorrhea, and congestion (Salz, 2025). Allergies may impair quality of life, reduce productivity, and disrupt sleep. Evidence suggests that diet and nutrition influence the development and severity of allergic diseases and can affect daily functioning. Emerging research also indicates that plant‑based dietary patterns may confer symptoms‑reducing benefits (Zhang & Vanderhoof, 2023).

Dietary components differentially regulate allergic‑inflammation pathways through host‑ and microbiota‑derived metabolites. A diverse range of nutrients—including vitamins A, D, and E; the minerals zinc, iron, and selenium; dietary fiber; fatty acids; and phytochemicals—modulate these pathways through immune‑ and microbiota‑derived mechanisms, thereby influencing allergy outcomes (Zhang & Vanderhoof, 2023). Numerous studies have shown that dietary patterns high in calories and saturated fat and low in dietary fiber—characteristic of the typical Western diet—may increase the risk of allergic diseases, including seasonal allergies, through several mechanisms, such as adverse effects on the gut microbiome. Conversely, Mediterranean dietary patterns rich in plant‑based foods such as fruits, vegetables, and unsaturated fats from olive oil and omega‑3–rich fish have been correlated with a lower risk of seasonal allergies. Gut health and diet are increasingly recognized as important factors influencing allergic‑inflammation pathways and symptom severity. These dietary and microbiome‑related factors contribute to immune regulation and inflammatory balance, which may help modulate the body’s response to seasonal allergens (Salz, 2025).

Quercetin, a flavonol within the polyphenol family, has been studied for its potential to modulate allergic inflammation by stabilizing mast cells and reducing histamine release. Although preclinical findings are promising, the broader clinical evidence remains inconclusive. Quercetin’s absorption from foods is relatively low, but supplemental forms may achieve higher bioavailability and have shown potential, though not definitive, benefits in preliminary studies. Some people consume locally grown honey believing that ingesting small amounts of local pollen will build tolerance and reduce allergy symptoms. However, research shows that honey primarily contains heavy, flower‑derived pollen grains, not the airborne tree, grass, and weed pollens responsible for seasonal allergies. As a result, honey does not provide meaningful exposure to the allergens that trigger allergic rhinitis, and individuals allergic to specific plants may even react to honey produced from those same sources (Breeding, 2017).

Diet and nutrition influence immune and inflammatory pathways that contribute to the severity of allergic symptoms. Numerous micronutrients—including vitamins A, D, and E; B vitamins; and the minerals zinc, selenium, iron, copper, and magnesium—serve as cofactors in immune‑cell development, epithelial‑barrier maintenance, and antioxidant defense. Dietary fiber, flavonoids, and omega‑3 fatty acids promote the production of short‑chain fatty acids such as butyrate, which support intestinal epithelial integrity and exert anti‑inflammatory effects. Collectively, these dietary components contribute to immune regulation and may help modulate the body’s response to seasonal allergens (Salz, 2025).