Experts have said allergies like hay fever could cause mental health issues by interfering with feel-good hormones in the body.
Mounting evidence suggests people who have allergies are more likely to have anxiety or show similar behaviours.
According to doctors, distress caused by being sick could raise the stress hormone cortisol, which in turn tampers with serotonin – a hormone responsible for mood.
And the experience of straining to breathe, wheezing, or feeling itchy could simply make people feel anxious.
Experts have said allergies like hayfever could cause ill mental health by interfering with feel-good hormones in the body (stock image)
Dr Ahmad Sedaghat, a professor at the University of Cincinnati, called the body's reaction to allergies 'sickness behaviour', and is a way of keeping a person indoors to recover.
And while allergic reactions cause inflammation as an immune response, the internal swelling has also been linked to conditions like depression.
Dr Sedaghat told The Atlantic: 'Evolutionarily, all animals have this reaction, called "sickness behaviour", when they're sick. It's meant to conserve energy.
'The problem is if you have persistent inflammation of the sinuses, what happens over time is that the inflammation essentially builds on itself, making the anxiety and depression worse, which makes it easier for the inflammation to cause more anxiety and depression, and you fall into a vicious cycle where you can't break out.'
Another biological explanation is that inflammatory chemicals in the sinuses leak into the blood and reach the brain and nervous system.
In children, the foods that most commonly cause an allergic reaction are milk, eggs, peanuts, tree nuts, such as walnuts, brazil nuts, almonds and hazelnuts, fish and shellfish, such as crab, lobster and prawns.
Most children that have a food allergy will have experienced eczema during infancy. The worse the child's eczema and the earlier it started, the more likely they are to have a food allergy.
In adults, the foods that most commonly cause an allergic reaction are peanuts, tree nuts,