Understanding Allergies

#biology #medicine #allergy #histamine #antihistamine #immunesystem

Most people know someone who has an allergy; they affect more than 1 in 4 people in the UK. But what even are they? How can something that loads of people love to have all the time (like peanuts) be really harmful for someone else? Are allergies curable? What do you do if someone around you is having an allergic reaction?

What Are Allergies?

Well, to understand this, you first have to know what the symptoms of allergic reactions are. There are a number of different things that happen to people who have allergies. People can experience anything from sneezing and a little rash to something really serious like their throat swelling up.

The most series effect of allergies is anaphylaxis, this is when someone's throat, tongue and/or face swells up and they can't breathe. It happens very quickly and can even cause death. Allergies are really serious.

What Causes Allergic Reactions?

An important fact that will help you a lot in biology is that every reaction in your body is caused by different chemicals, these chemicals are called proteins.

You've probably heard that there is protein in your food and it makes you get big and strong, but really this is just one type of protein. There are thousands and thousands of different proteins in your body. They all have different shapes and they all do different things.

Each reaction that happens in your body depends on which proteins are involved and there are hundreds of reactions going on in your body every minute!

The protein that is involved in allergy is called histamine and it's quite nasty.

Whenever the person is in contact with the thing they are allergic to, your body releases histamine. The histamine protein is what causes the itchiness, sneezing, or swelling that happens in an allergic reaction.

This is what a histamine protein looks like - remember proteins are tiny, like really tiny - they're even smaller than the cells in your body!

So Why Do We Have Histamine if it's Harmful?

You probably think histamine sounds awful and are wondering why we even have it inside our bodies.

But think about this: if people with allergies feel itchy, sneezy, or generally ill when they have a reaction - what do those effects that seem similar to?

It's very similar to how everyone feels when they have a cold or the flue. That's because allergic reactions and illnesses like the flue happen in similar ways.

Histamine plays a very important role in fighting off diseases and infections. It is an important protein in our immune system. This is the thing in our body that is responsible for fighting off disease, whenever you get sick it is your immune system that works hard to fight off that sickness.

Therefore, if we didn't have histamine, whenever we got sick, we wouldn't be able to fight it off! That is even worse than allergies.

But Why Are Only Some People Allergic to Stuff?

The thing is, allergies may be common, but they aren't normal. They happen when a person's body thinks something is harmful when actually it isn't. Usually, when something harmful enters our bodies (like the flu), our bodies can tell it's harmful and can fight it off using chemicals like histamine.

What do you think our bodies use to tell if something is harmful?

Hint - it's been mentioned in this article...

The Immune System - Allergies happen when someone's immune system malfunctions.

Can We Cure Allergies?

Currently, there is no proper cure for allergies. You just have to avoid being in contact with whatever you're allergic to. However, if you do come in contact with it (for example if someone who's allergic to cats touches a cat and has a reaction), there are some medicines that can help with the effects of the allergy.

First of all there are some medicines called anti-histamines. What do you think they do?

They block the histamine proteins from taking effect so you get less of a reaction.

Also, there is an injection called an EpiPen. EpiPens are only used for the most serious allergies because they are very dangerous. They releases a chemical (another protein) called adrenaline.

Adrenaline has loads of different functions in our bodies and is naturally released when you're scared or excited (people who like to do scary things like go on roller coasters are often called adrenaline-junkies because they like the effects of adrenaline). One thing it does is stops allergic reactions. When inside the body, adrenaline triggers a bunch of other proteins to minimise the allergic reaction.

People with serious allergies have to carry around an EpiPen in case they need to use it suddenly.

But remember, too much adrenaline is really, really dangerous so never play with an EpiPen.

What questions do you have about allergy?

What's the weirdest thing you've ever heard someone is allergic to?

Get in touch!!