Pollen counts have skyrocketed this month – the start of six months of misery for millions of hay fever sufferers.
But can changing your diet and avoiding certain foods help you avoid the constant runny nose and watery eyes?
Here, MailOnline examines which foods to stay away from if you don’t want to make your sniffles worse.
Blue cheese, red wine and bacon, as well as fruit, can trigger hay fever symptoms due to their high amounts of histamine and pollen
Old cheese
It’s not good news for cheese lovers, as experts say the histamine in certain types of cheese can wreak havoc on people with hay fever.
Histamine is the chemical that causes an allergic reaction.
Usually, histamine is released when the body detects something harmful, such as an infection. It causes blood vessels to expand and the skin to swell to protect the body.
But in people with allergies, the body sees harmless things, such as pollen, dust, or animal hair, as a threat and produces histamine.
This causes the well-known allergy symptoms of itchy eyes, runny nose, sneezing and skin rashes.
But histamine is also present in some cheeses, especially aged and fermented cheese.
Histamine is produced by bacterial microbes, which grow on the rind of aged cheese to help it ripen and protect it from harmful pathogens, according to a 2019 article published in Scientific Reports.
Dr. Adrian Morris, an allergy specialist from the Surrey Allergy Clinic, said: ‘If you have an allergy and you react to the pollen, you release histamine.
‘If you then eat food that is rich in natural histamine, you are more likely to have slightly worse symptoms.’
Cheeses such as Stilton, Roquefort, Parmesan, Blue Brie, Camembert, Cheddar, Feta, and also natural yogurt can cause this histamine reaction in some people.
But he added that not all dairy causes this problem.
Dr. Morris said, “It must be fermented dairy. You don’t have to avoid milk and cottage cheese, because that’s not a problem in these foods.’
Red wine
Just like fermented cheese, wine is also packed with histamine.
“If you’ve had a glass of red wine and you have hay fever, you’re going to sneeze more,” says Dr Morris.
Histamine is produced during the fermentation and aging process of wine.
But red wine, he says, has 20 to 200 percent more histamine than white wine Drink well.
Red wine has between 60 and 3,800 micrograms of histamine per liter.
This is believed to be because red wine is fermented with seeds and skins, which create higher levels of tannin – another potential irritant that creates more histamine.
In addition to red wine, cider, real ale, and even balsamic vinegar can make hay fever symptoms worse, Dr. Morris says.
But beer may not have as much influence as wine. That’s because beer contains between 21 and 305 micrograms of histamine per liter, according to Drinkwell.
Salted meat
Bacon can’t be on the menu if you find it aggravating your symptoms.
That’s because cured meats, such as salami, pepperoni, and processed ham, are high in histamine.
Chicken liver, pies, processed chicken and any leftover meat can also trigger a reaction, Dr. Morris said.
He said, “They contain naturally occurring histamine, so when you eat them, they fill your body with histamine.” You could have a combination of them, and the levels could go up slightly.
“Most people metabolize it just fine and it’s not a problem.” But some people sneeze more and it makes them itch more.’
Experts say that if you then eat foods rich in natural histamine, you’re more likely to have slightly worse symptoms. That includes cured meats and aged cheese like blue cheese pictured above
He noted that fish, including tuna, salmon, mackerel, caviar, pickled herring, and oysters, can all increase your histamine levels.
And how these foods are prepared, according to a 2017 Korean study published in Annals of Dermatology.
Grilled pork, for example, had the highest histamine levels compared to uncooked or cooked pork, reducing histamine levels by 60 percent.
Chocolate
Chocolate is thought to trigger hay fever sufferers’ worst enemy: histamine.
Even without containing high levels of the chemical, some foods and drinks can trigger the body’s mast cells — located in the skin, lungs, nose, mouth, gut and blood — to release histamine.
Certain foods can also block the activity of the enzyme diamine oxidase, which is involved in the breakdown of histamine.
Chocolate triggers both processes, according to a 2007 article published in The American Journal of Clinical Nutrition.
This means that although chocolate is low in histamine, it can trigger the release of the body’s existing histamine.
Chocolate also contains other biogenic amines — chemicals in food, of which histamine is one type — that slow the breakdown of histamine, according to Fig, an app to help people with dietary restrictions.
Melon
The refreshing summer fruit may not be the best snack for hay fever sufferers.
Unrelated to the effects of histamine, certain fruits, vegetables, nuts, and grains can trigger hay fever symptoms, Dr. Morris says.
Oral allergy syndrome, also known as pollen-food syndrome, occurs when the body mistakes the pollen structure of foods for those found in trees, grass, and weeds.
Oral allergy syndrome is a form of hay fever caused by certain types of pollen, the main three being birch, grass and ragweed. Cantaloupe is a major culprit for people with pollen-food syndrome as it is bad for those who are sensitive to both grass and ragweed pollen
This cross-reaction means that the immune system recognizes the dietary protein as an allergen and triggers an allergic reaction.
Symptoms may include swollen lips, an itchy mouth, and an itchy inner ear.
A whole host of fruits can cause this reaction, but cantaloupe is a big culprit for people with pollen-food syndrome, as it’s bad for those who are sensitive to both grass and ragweed pollen.
If you are sensitive to birch pollen, foods such as apples, carrots, parsnips, pear, onions, tomato, wheat, celery, fennel, peanuts, walnut, peach, potato, and kiwi, among others, can cause a reaction.
Other pollens can also cause itching.
Grass pollen reaction can be caused by melon, orange and tomato.
Mugwort pollen reaction can be caused by celery and watermelon.
Ragweed pollen can also cause a reaction from bananas, honey, chamomile tea and sunflower seeds.
But these allergy symptoms vary from person to person.
Dr. Morris said, “People with this condition will not respond to all foods, but they may respond to four or five of them.”
He added: ‘Only cut things out if you find it’s a problem, but I wouldn’t avoid all of these foods because they may not be reactive.
‘Some people are allergic to pollen and grass and do not react to the fruits. But it’s good to be aware of it.’
But like histamine in meat, the way you cook your food matters when it comes to pollen allergies.
Dr. Morris said, “If you cook the food, you can reduce the allergy.”
‘People say that when peeling potatoes they get itchy hands and have to sneeze, but if they eat a naked potato it’s all right.
‘This is because the heating damages the protein, making them less of a problem.’