Could you have a coffee allergy? 19 signs you should lay off the latte

A simple cup of coffee will leave some people feeling nervous, liable to insomnia – or worse. Here are some of the warning signs of a caffeine allergy.

We Brits are undeniably a nation of coffee lovers. Recent studies suggest that, as a country, we drink upwards of 95 million cups a day.

Many people rely on a cup of java to get them started in the morning, keep them going in the afternoon or perk them up at the end of a long and slightly tedious evening dinner. But could that ‘hit’ be hitting a little harder than you thought?

[Read more: Is decaffeinated coffee better for you?]

While being allergic to coffee is relatively uncommon, it’s not unheard of. And for some people, their body doesn’t see those molecules of caffeine as a welcome pick-me-up, more a foreign and dangerous invader.

“A food allergy is when the body's immune system reacts unusually to specific foods,” says Shona Wilkinson, nutritionist. “Allergic reactions are often mild, but they can sometimes be very serious.”

Including, of course, a serious reaction to – if not specifically coffee – certainly the high levels of caffeine in it.

Hypersensitive

“Studies have shown that people can have anaphylactic reactions to caffeine,” explains Wilkinson, “and this can be confirmed by a simple skin prick test.

“There is genetic evidence regarding the inability to process caffeine as some people lack the genes responsible for this or the genes aren’t being expressed as they should be.

“This allows caffeine to build up in a person’s body rather than being broken down properly. These people are described as hypersensitive to caffeine.”

Symptoms of a caffeine allergy

So how do you know if you’re one of these people? Wilkinson explains the signs might include one, or a few, of the following:

• Skin problems such as hives, eczema, rashes, acne, severe itching
• Headaches or migraine
• Anxiety and panic attacks
• Can’t focus or concentrate
• Tongue, glands, or throat swelling
• Racing heart or palpitations
• Angry, irritable, bad mood
• Fatigue
• Dizziness
• Extreme jitters
• Chest Pain
• Depression
• Numbness in face, hands, or feet
• Muscle pain
• Shortness of breath and tightness of chest
• Delusions or hallucinations
• Cold- and flu-like symptoms
• Vision problems
• Cold sweats

Why does it happen?

Some years ago, an EU Scientific Committee on Food looking at the effects of caffeine noted that a dose of 5mg caffeine per kilogram bodyweight (300mg for a 60kg person) could result in “transient behavioural changes, such as increased arousal, irritability, nervousness or anxiety in some people, particularly if they were normally low consumers of caffeine”.

What can you do about it?

“If you think you may be intolerant to caffeine, try eliminating it from your diet completely, but remember it can take up to two weeks for all of caffeine’s effects to wear off.”

Remember too, it’s not just coffee: “A surprising number of food and drink items contain caffeine, including chocolate and even decaffeinated drinks," says Wilkinson - so if you think caffeine might be a problem for you, make sure you check your food and drink labels carefully.

[Read more: How is a flat white different to a latte or a cappuccino?]

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