A Week of Anxiety – sounds awful doesn't it? I know – I've been there. The racing heart, the the swirling thoughts, the sweating, the shaking – sometimes it can seem you're about to have a heart attack. It's one of the scariest feelings in the world and also one of the most common; according to the Mental Health Foundation, mixed anxiety with depression is the most widespread mental disorder there is.

However in this instance, I hope a week of anxiousness is a good thing. Because today is the start of Mental Health Awareness Week, which this year focuses on anxiety, so over the next seven days I'm going to be blogging on the subject. I'm Sarah Rayner, an author, and each day I'll be taking a letter from the word as a focus – today is 'A', for adrenaline.

It's a good place to start talking about anxiety, because the role it plays is key.

So, what exactly is anxiety? Personally, it's a word I'd use to describe feeling nervous and panicky. It's normal to be anxious in stressful situations – during exams, before public speaking; if confronted by fear. In fact it can be helpful to be anxious – imagine being threatened by an aggressive animal. Here the burst of adrenaline would bring about a much-needed 'fight or flight' response, useful if you need to escape from a hungry lion.

Adrenaline is linked to blood supply; it drives oxygenated blood into the limbs for a quick getaway and brain so we can make split-second decisions. Blood is taken from areas of the body where it's not needed, such as the stomach, because in a life-threatening situation, you're not going to stop for food. This is often why when you're stressed, you feel sick and unable to eat. Adrenaline is also what lies behind the palpitations, perspiration, racing thoughts and shaking.

Whilst the physical symptoms of anxiety can feel horrible, anxiety is only a problem when it becomes out of proportion, persistent or appears for no apparent reason. This is when the body reacts inappropriately to the strains of everyday living and adrenaline production is triggered in response to situations where we don't actually need to run away or fight for survival. In other words, although we – luckily – live in world where encounters with lions are relatively few and far between, in an anxious person, the body is reacting as if there are hungry lions round every corner.

If you suffer from bad anxiety, you may be aware of this already, but I hope it's useful to be reminded. I find it's easy to get caught up in a cycle of worry and start to panic about the bodily sensations of anxiety as much as the situation that triggered it. When this happens, I gently tell myself it's only anxiety, only adrenaline, that in itself it can't harm me.

I suggest you do the same; even when you're unsure why you're anxious, remind yourself there isn't a lion about to eat you.

Sarah Rayner

A Moodscope member.

Don't forget! Every day during Mental Health Awareness Week, Moodscope is giving away a signed copy of Sarah's new novel, Another Night, Another Day. Its focus is mental health – one of the characters has to cope with bad anxiety and some Moodscopers might find reading of her journey a comfort. Just email support@moodscope.com with 'Giveaway' as the subject and we'll pick one person each day to receive a free signed copy.

Caroline

The Moodscope team.