An itchy, runny nose. Red eyes. Wheezing, sneezing and angry, blotchy skin. It’s not a good look. But these are all symptoms that affect a surprisingly large number of us – in other words, people with allergies.
According to the NHS, at least one in four people in the UK has one or more allergies at some point. And anyone – even the healthiest among us – can be affected, from babies to centenarians.
What we don’t know is exactly why some people develop allergies while others don’t. There could be a genetic link since some types of allergies can often run in families (this is called atopy). Scientists have even tried to pin allergy susceptibility down to specific genes, with one study identifying no fewer than 132 genes that may be involved with the allergy process.
What causes allergies?
Thankfully, we do know a lot more about how allergies develop. And at the centre of everything is the immune system:
• Your immune system protects against infection from viruses, bacteria and other nasty organisms – it recognises invaders, hunts them down, and destroys them.
• If you have an allergy, your immune system recognises something harmless as being a threat and acts to destroy it. These harmless substances are called allergens.
• The process that starts an allergy is called sensitisation, and it can happen the first time you come into contact with an allergen or at any time, even if you’ve been exposed to the allergen for years.
• Once sensitised to an allergen your immune system reacts the next time you’re exposed to it. This sets off a chain of events, one of which is the release of a chemical called histamine. When released into your system histamine causes a range of allergy symptoms, including itching, sneezing, wheezing, and skin rashes.
Did you know? A weak immune system can leave you more susceptible to infections. But allergies are the result of your immune system reacting strongly to an allergen. So if you have the sniffles all the time it may not be a sign that your immune system is below par – in fact, you could argue it’s quite the opposite.
There are many different allergens but the ones that cause most allergic reactions include pollen, dust mites, moulds, pet dander (particles of skin shed by animals with fur or feathers), insect venom, medicines, and foods. These cause a range of allergies, including:
Allergic rhinitis There are two types - seasonal (hayfever) and perennial, which affect you all year round (cold-like and itchy nasal symptoms).
Asthma Breathlessness, wheezing and a tight chest caused by inhaling allergens (though other things can trigger asthma too).
Eczema When the skin comes into contact with an allergen it becomes itchy, dry, cracked, and sore.
Urticaria Also known as hives (itchy, raised red patches or spots).
Allergic conjunctivitis Watery, itchy, sore, and puffy eyes that feel hot and gritty.
Food allergy Reactions to foods including fish, shellfish, nuts, milk, and eggs causing rashes, wheezing, and itching (not to be confused with food intolerance, which typically triggers digestive discomfort and migraine). Food allergies can be serious and even life-threatening (see When allergies get serious, below).
Did you know? Allergies are on the rise. We don’t know exactly why, but one theory is that today’s environments are so clean and free of germs (relatively speaking), that our immune systems have less to deal with and start reacting to harmless substances instead. This is backed by studies suggesting children who spend their early years on a farm have fewer allergies later.
All that pollen's making me sneeze
Of course, it’s no coincidence we’re talking about allergies right now, just as summer is approaching. Hay fever is a common allergy, with more than 45,000 people seeing their GP with symptoms a week during peak pollen season in England alone. But hay fever doesn’t just happen in the spring and summer months. It’s triggered more than 30 types of tree, grass, and weed pollens, some of which can be released as early as January and as late as September:
Tree pollen This is usually released in late March and continues to mid-May, though alder, hazel, and yew pollens can sometimes be released in January while pine and lime pollens can continue through July.
Grass pollen The grass pollen season typically runs from mid-May to July, but it has been known to start early in May and last until September.
Weed pollen Plants like rape seed, plantain, nettle, dock, and mugwort start releasing pollen at the end of June and continue until September (though the season can last longer).
If you’re truly unfortunate you could be allergic to several types of pollen and sneeze your way from winter through spring and summer and on to autumn.
Did you know? Flower pollen is relatively heavy and sticky, which means it doesn’t usually become airborne and causes hay fever symptoms. Tree, grass, and weed pollens are lighter, so they’re more likely to linger in the air and reach your eyes, nose, and mouth.
Summer is also less fun for anyone who’s allergic to bug bites (imagine trying to relax at a picnic or barbeque with legions of angry wasps buzzing around if you’re allergic to wasp venom). Even staying indoors isn’t an option if you react to dust mites (though to be fair that’s a problem all year round, not just during the summer).
Did you know? Bee and wasp venoms contain different allergens (phospholipase A2 and melittin in bee venom and antigen 5 in wasp venom, in case you were asking). Thankfully, scientists say those who are allergic to one type are rarely allergic to the other.
When allergy gets serious
Any allergy can make life miserable, but some people have far bigger problems. A severe allergic reaction – often caused by insect bites or stings, foods, or medicines – is called anaphylaxis.
With anaphylaxis symptoms start suddenly, get worse very quickly, and can be very severe. These include breathing difficulties, lightheadedness or fainting, rapid heartbeat, clammy skin, anxiety, and losing consciousness. Since it can be potentially life-threatening, anaphylaxis is classed as a medical emergency.
Someone who has anaphylaxis will usually wear a medical emergency bracelet and carry an adrenalin pen (an EpiPen, for example). If you ever see someone going into an anaphylactic shock, call 999 immediately. You may also have to help them administer their adrenalin shot – just don’t go all Pulp Fiction and try stabbing the needle into their heart – a leg, arm or any other muscle will do just fine!
Did you know? According to Patient UK, half a million people in the UK have had an anaphylactic reaction to venom from bees or wasps, while almost a quarter of a million under-45s have had anaphylaxis caused by nuts.
How to get some relief
Avoiding your particular allergen is undoubtedly the best way to keep allergy symptoms under control. But it’s not always practical. Thankfully modern medicine has a few tricks up its sleeve to help allergy sufferers live normally. Antihistamine lotions and creams for skin reactions, antihistamine nasal sprays and eye drops for the nose and eye symptoms, and decongestants to help unblock a blocked nose.
If you don't get on with antihistamines for whatever reason, natural remedies such as bromelain, nettle, and quercetin can be effective for some people. Untimely immune-boosting shot of high-strength vitamin C has also been identified as a safe, natural allergy therapy.
However, a lesser known influence on your allergic response is gut health, because your gut microbiota supports your immune system. There’s even evidence to suggest taking probiotic supplements to keep your gut flora healthy can help relieve allergies and help prevent them. A review of atopic dermatitis studies has also found arguments to support using probiotics for eczema.
• Fancy trying a probiotic? Our Bio Cultures Complex Advanced Multi-Strain Probiotic has 45 billion CFUs from 17 probiotic strains and is fortified with prebiotics – plus it’s suitable for adults and children.
Other helpful supplements include a b-vitamin complex to support your immune system and health in general. Omega-3 fish oils are another good option, with a study suggesting diets rich in omega-3 fatty acids and vitamin C could reduce the risk of hay fever. And let’s not forget vitamin D3: research claims it may improve asthma symptoms in older people with low vitamin D levels. It's also worth maintaining your levels of magnesium and zinc, both of which have key roles in keeping your immune system healthy.
How Gut Health Affects Your Whole Body