Fibromyalgia Syndrome Causes: What We Know So Far

Fibromyalgia syndrome causes are not fully understood, and no single cause has been found. If you have been asking yourself "what did I do to bring this on?", the honest answer is: nothing. Researchers are still putting the picture together. Here is what they think so far, in plain words.

There is no single cause

Fibromyalgia is a long term condition that causes pain all over the body, often with deep tiredness and poor sleep. The NHS says that as many as 1 in 20 people could live with some degree of it (NHS, 2022). With so many people, it would be odd if one cause explained everyone.

Most researchers now think several things combine. A sensitive nervous system, your genes, and a trigger may all play a part. The mix is different from person to person. That is why two people with the same diagnosis can tell very different stories about how it began.

The leading idea: a nervous system that turns up the volume

The idea with the most support is called central sensitization. Your brain and spinal cord are the "central" part of your nervous system. They receive pain signals from the body and decide how loud to make them.

In fibromyalgia, that volume dial seems to be set higher than usual. A touch, a long walk or a bad night can then register as pain, or as more pain than you would expect. The signals are real, and so is the pain. What changes is how strongly the nervous system amplifies them.

This is why the muscles and joints usually look normal on scans. The difference seems to lie in the processing, not in damaged tissue. For a closer look, read our guide to central sensitization.

If you have wondered whether the pain is real, our page on whether fibromyalgia is a real condition answers that directly.

What can set it off

Many people can point to a moment when things changed. Common triggers include:

• An injury or accident
• An infection or illness
• Surgery
• A long period of heavy physical or emotional stress

The NHS notes that it is often triggered by an event that causes physical or emotional stress. A trigger is not the same as a cause, though. It may be the push that tips a sensitive system over. Other people have no clear trigger at all, and the symptoms simply build up over time.

Family, sleep and other conditions

Genes may play a small part too, and fibromyalgia sometimes runs in families. That does not mean you will get it if a relative has it.

Sleep is closely linked too. Poor sleep is a common part of fibromyalgia, and it can make pain feel louder, while pain can make sleep harder. Researchers are not sure which comes first for each person. For many, it becomes a loop.

Fibromyalgia can also appear alongside conditions that affect the joints, muscles and bones, such as rheumatoid arthritis, osteoarthritis or ankylosing spondylitis. These are separate conditions, and fibromyalgia itself does not damage or inflame the joints. If you have one of them, your doctor can help you tell which symptoms come from which. Our page on a fibromyalgia flare explains how symptoms can shift from day to day.

What it is not

It is not damage or inflammation in your muscles. It is not a sign that you were weak, lazy or careless. You did not cause it by resting too much, working too hard or feeling stressed. A body can become sensitive for many reasons, most of them outside anyone's control.

You can read more in our Feldypedia article on fibromyalgia and widespread sensitivity.

Where gentle movement fits

Knowing the likely causes can take some blame off your shoulders. It also hints at what may help. If the nervous system is turned up, slow and calm attention to movement may give it a gentler experience of your body. The Feldenkrais Method® is built around this kind of attention. It uses small, slow movements and curiosity about how you move, never effort or pushing through pain.

This is supportive self care, not a treatment, and it does not replace your doctor. If you would like to try gentle movement, our page of exercises for fibromyalgia shows what a small, slow dose can look like. Feldy, an online Feldenkrais® program, builds its lessons around the same idea. Before you try anything, talk with your doctor, and stop if something hurts.

Find where to start

You do not need to work out the cause before you look for a gentler way of moving. A short quiz can point you toward a movement method that suits how you feel today.

Not sure which movement method fits you? Take the 60 second Movement Match quiz and see which approach to gentle movement may suit you, in three quick questions.

Common Questions about fibromyalgia syndrome causes (FAQ)

Is there a single cause of fibromyalgia?

No. Researchers have not found one cause. Most believe several things combine, such as how the nervous system handles pain, your genes, and a trigger such as illness, injury or heavy stress. Different people may reach the same condition by different routes.

Can stress cause fibromyalgia?

Stress may play a part. Many people say their symptoms began after a hard period, a loss or an injury. But stress alone does not explain it, and plenty of people with fibromyalgia can name no trigger at all. Stress is better seen as one possible piece of a larger picture.

Is fibromyalgia genetic?

Research suggests genes may play a small part, and it sometimes runs in families. Having a relative with fibromyalgia does not mean you will get it, and many people with the condition have no family history.

Is it safe to move gently if I have fibromyalgia?

Slow, comfortable movement is generally considered safe for most people, as long as it stays well below pain and you go at your own pace. Stop if something hurts or you feel unwell. Check with your doctor first if you are unsure, especially if your symptoms are new or changing.

How is fibromyalgia different from arthritis?

Arthritis involves inflammation or wear in the joints, and it can show up on scans and blood tests. Fibromyalgia is mainly about how the nervous system processes pain, so the muscles and joints usually look normal. The two can exist together, which is why a doctor needs to assess you.

How long does it take to know the cause of my symptoms?

It varies. There is no single test for fibromyalgia, so a doctor usually reviews your symptoms and rules out other conditions first. That can take several visits. Keep notes on your symptoms and bring them along to help.

Which symptoms mean I should get checked by a doctor?

Book a doctor visit if you have pain all over your body or deep tiredness that lasts. Go sooner if symptoms are new, severe or changing, or if you have fever, weight loss or swollen joints. Fibromyalgia is best managed with a care team.