Lenny and Larrys
Your eyes are itching, your nose will not quit, and this year feels worse than usual. You are not imagining it. A strengthening El Niño and a steadily warming climate are combining to make pollen seasons longer and more intense across the United States. An over-the-counter antihistamine helps, but there is also a food-and-vitamin pairing with real science behind it: quercetin, a plant compound that calms the cells driving your symptoms, and vitamin C, the partner that makes it work harder.
Before you begin - always consult your physician before beginning any exercise (or dietary) program(s). This general information is not intended to diagnose any medical condition or to replace your healthcare professional. Consult with your healthcare professional to design an appropriate exercise prescription (or dietary program) that's right for you.
Why are seasonal allergies so bad this year?
Allergies are hitting harder this year because a strengthening El Niño is layering onto a longer-term climate trend: warmer temperatures and rising carbon dioxide are stretching pollen seasons and driving pollen counts higher.
NOAA issued an El Niño Advisory in June 2026, confirming the pattern has formed and is expected to intensify through the coming winter. El Niño reshuffles rainfall and temperature across the country, and its effects grow strongest in the colder months. The bigger driver of your daily misery, though, is the slow warming underneath it. Research shows that warmer temperatures and higher carbon dioxide lengthen the pollen season and increase both the volume of pollen plants release and, for species like ragweed, how allergenic that pollen becomes. Longer seasons plus heavier, more potent pollen loads mean more days of exposure and stronger reactions, which is why this spring and summer feel relentless. So what can you actually eat to fight back?
What is the best natural antihistamine you can eat?
Quercetin is the best-studied natural antihistamine you can get from food, because it works upstream: it stabilizes the mast cells that release histamine rather than only blocking histamine after your body floods with it.
When an allergen lands, immune cells called mast cells burst open and release histamine, the chemical behind your sneezing, congestion, and watering eyes. Quercetin, a flavonoid concentrated in red onions and apple peels, calms those cells before they fire. In laboratory studies, quercetin matched or outperformed cromolyn, a prescription mast cell stabilizer, at blocking histamine release from human mast cells. A 2025 analysis of animal studies found that quercetin consistently lowered histamine and other allergy mediators, and rodent models of allergic rhinitis show it eases sneezing, congestion, and nasal itching.
Here is the honest catch: most of that evidence comes from cells and animals. Human trials of quercetin on its own remain scarce, so treat it as promising remedy rather than settled. The richest food sources are capers, followed by red onions (the most practical everyday option), apples eaten with the skin, berries, and kale. The real problem is dose. Your body absorbs only a small fraction of the quercetin in food, and the amounts used in research, often 500 to 1,000 mg a day, are tough to reach from meals alone. That gap is why supplements exist, and why phospholipid-bound formulations are built to absorb far better than plain powder. Quercetin also works best as prevention, so starting a few weeks ahead of your worst season tends to beat reacting once symptoms peak. One caution: quercetin can interfere with how your body processes certain medications, including some blood thinners, so check with your doctor before adding a supplement.
How does vitamin C make quercetin work better?
Vitamin C is the ideal partner for quercetin because it helps your body clear histamine and can regenerate quercetin so it keeps working longer.
Vitamin C attacks the problem from the other end. Instead of stopping histamine release, it helps your body break histamine down. Studies have documented an inverse relationship between the two: as blood vitamin C falls, histamine rises, and raising vitamin C levels lowers circulating histamine. It is also one of the easiest nutrients to get from food. A single red bell pepper delivers more than a full day's vitamin C, and oranges, strawberries, kiwi, and broccoli stack it up fast.
The two compounds also reinforce each other. In lab work, vitamin C can regenerate quercetin after it has done its job, letting a given amount keep working longer, which is one reason the pair turns up together in both research and supplements. To put this on your plate, build snacks and meals around both: sliced red onion and apple with the skin for quercetin, plus peppers, citrus, or berries for vitamin C. A kale salad with red onion, strawberries, and a handful of capers covers the whole pairing in one bowl.
Your Best Bet When the Pollen Spikes
No food will replace your allergy medication on a high-pollen day, and quercetin's human evidence is still catching up to its lab results. But this pairing is cheap, low-risk, and grounded in real science: quercetin calms the cells that release histamine, and vitamin C helps clear what does get released while keeping quercetin in play. With El Niño strengthening and pollen seasons stretching longer each year, loading your plate with red onions, apples, peppers, and berries is a smart year-round habit, not just a seasonal scramble. Start early, stay consistent, and let your diet shoulder some of the work your antihistamine usually handles alone.