The physical symptoms of anxiety, and why they are real

Barely a week goes by without someone in my consulting room apologising. They describe a pounding heart, a tight chest, a stomach that will not settle, and then they say the same thing: sorry, it is probably just anxiety. I would like to take that word just and gently remove it. If anxiety is making your heart race and your chest tighten, those sensations are real. Your body really is doing them. They are not imagined, they are not a sign of weakness, and they are not all in your head. They are physiology.

The short version

• The physical symptoms of anxiety come from a real stress response, not from imagination.
• Adrenaline and cortisol prime your body for action, which is why you feel it in your heart, your breathing, your gut and your head.
• These sensations are horrible but, on their own, usually not dangerous.
• Some of them can overlap with physical illness, so it is sensible to get new or unusual chest pain, breathlessness or a racing heart checked at least once.

Why anxiety shows up in the body

When your brain senses a threat, real or imagined, it releases stress hormones, mainly adrenaline and cortisol. This is the fight-or-flight response, and it exists to keep you alive. As the NHS puts it, those hormones can be helpful in some situations, but they can also cause physical symptoms such as an increased heart rate and increased sweating.

The trouble is that the system cannot tell the difference between a charging animal and a difficult email. It fires either way. Adrenaline speeds up your heart, quickens your breathing and tightens your muscles, readying you to run or fight. Faced with a real emergency, you would burn all of that off. Sitting at your desk, you are left with the raw sensations and nowhere to put them. That is anxiety in the body: a survival response switched on at the wrong moment.

The symptoms, one by one

Your chest

A faster, harder or more noticeable heartbeat is one of the things people notice most, along with chest pain or tightness and a sense of breathlessness. It is frightening, precisely because the chest is where we all fear something serious. But a racing or thumping heart is exactly what adrenaline is built to produce. The tightness tends to come from the chest muscles bracing and from breathing higher and shallower than usual.

Your gut

Your gut is extraordinarily sensitive to how you feel, because the gut and the brain are in constant two-way communication, a link researchers call the gut-brain axis. When you are anxious, that same stress response unsettles your digestion, which is why anxiety so often brings a churning stomach, nausea, a loss of appetite, or a sudden urgent need for the loo. The knot in your stomach is not in your head. It is in your gut, and it is real.

Your head

Feeling lightheaded, dizzy or slightly unreal is common, and it usually comes down to breathing. When we are anxious we tend to over-breathe, taking faster or deeper breaths than the body actually needs. This lowers the level of carbon dioxide in your blood, which narrows the blood vessels to the brain a fraction and can leave you feeling dizzy, sometimes with tingling in your fingers, lips or face. It sounds alarming. It is, reassuringly, one of the more harmless things your body does, and it settles as your breathing settles. One old piece of advice worth dropping: breathing into a paper bag is no longer recommended, so please do not. Slow, steady breathing is all you need.

The rest of you

Anxiety also turns up as sweating, shaking or trembling, headaches, feeling hot, muscle tension and plain tiredness. In a sudden surge, a panic attack, several of these can arrive at once: a pounding heart, shortness of breath, dizziness, tingling and a feeling of losing control. It is deeply unpleasant. It is also, in itself, not dangerous, and it usually peaks and passes within five to thirty minutes.

The sensations are real, they are your body doing exactly what it evolved to do, and understanding that is often the first thing that takes the fear out of them.

When to get it checked

Here is the balance I try to strike with patients. Anxiety symptoms are real but usually harmless, and yet some of them, chest pain, breathlessness, a racing heart, can also point to something physical. The answer is not to panic, and not to ignore them either. If a symptom is new, if it is different from your usual pattern, or you are simply not sure, it is completely reasonable to see your GP and have it looked at once. Do not try to diagnose yourself. Getting the all-clear is never a waste of anyone's time, and it often lifts a real weight.

Some things should not wait. Call 999 if you have chest pain that feels tight or like squeezing, or chest pain that spreads to your arms, neck or jaw, or if you are having severe difficulty breathing. These can be signs of a heart problem, and it is always better to be checked than to wait it out. Call NHS 111 if you are suddenly more short of breath than usual, or you have chest pain with feeling sick, or your heart feels like it is racing, slowing or skipping a beat. And if you think you might have an anxiety disorder, or what you are trying yourself is not helping, that is worth a routine GP appointment too. In England you can also refer yourself directly to NHS talking therapies, which I go into in when should you see your GP about anxiety.

Learning to read your own symptoms takes a surprising amount of the sting out of them. Once you know that the thump in your chest is adrenaline rather than disaster, it loosens its grip, and simple breathing tools, like the ones in the brightloaf app, become far easier to reach for.

This article is for general information and is not a substitute for personal medical advice. If you are worried about physical symptoms, or you are in crisis or at risk of harm, contact your GP, call 999 or NHS 111 in the UK, or a crisis line such as Samaritans on 116 123. brightloaf is not a crisis service.