What causes tension headaches?

Are headaches normal?

Because headaches are widely considered ‘normal’, many people see no reason to consult a doctor. A common belief is that headaches are no big deal, they just come and go. Most people self-diagnose and reach for pain relief without medical guidance. The truth is that different types of headache have different causes and require different treatments. So in fact, a proper medical diagnosis is essential. In addition, any painkiller use should be supervised by a doctor and closely monitored. As well as the general side effects painkillers can have, improper use can result in a condition called “medication overuse headache”. This is a very distressing type of headache that requires extensive treatment.

Tension-type headaches are widespread

The one-year incidence of tension headache is 86% in people aged 12 to 41. In other words, 86% of people in this age group suffer from tension headaches at least once within a year. These figures indicate that tension headache is remarkably common. Studies suggest peak occurrence in the 30 to 39 age group. The rate declines with age. Globally, the number of people affected could be as high as 2 billion. With such a large number, tension-type headaches are the third most common condition of all.

The reported frequency of tension headaches ranges from about once a week (10%) to several times a month (24–37%). Two to three percent report very frequent, or even constant, tension-type headaches. In such cases, the condition is considered chronic. Some patients also suffer from migraines as well. In chronic cases, other related conditions are particularly common. These typically include depression, mood disorders and anxiety disorders. Tension headaches are classified as chronic when they occur more than 15 times per month. Most people have much less frequent “episodic” tension-type headaches, with no more than 15 attacks per month. However, this can still be a major burden and significantly impair quality of life.

Tension-type headache: under-researched?

Headache research is always complicated. The processes involved are not easy to visualize or explain. Research into the causes and connections behind different types of headache is ongoing to this day. New findings emerge all the time, causing existing assumptions to be revised and sometimes disproven. Tension-type headaches have also been researched for some time, resulting in various theories on what causes them and how they develop.

Compared to migraines, another common headache type affecting up to 15% of the population, tension headaches are more widespread, yet less studied. This could be because this type of headache is often dismissed as an everyday occurrence, although it significantly impairs day-to-day life.

New findings on the causes of tension headaches

Leading researchers agree that many factors contribute to tension headaches. External influences usually play an important role. Inside the body, tension headaches can happen when the body’s pain regulation system overreacts and starts firing off pain-triggering signals non-stop. This makes the nervous system more sensitive, with the result that even small, harmless sensations can start to feel painful. This increased pain sensitivity always increases the risk of the headaches becoming chronic.

New studies highlight three main factors in the development of tension-type headaches:

1. Tension in the head

The skull bones are covered by a layer of connective tissue. Tension can build up here. This tension is likely caused by the activation of certain pain sensors (called “nociceptors”). These are found around blood vessels, tendons and in parts of the connective tissue. Research has shown a direct link between the frequency and intensity of pain sensor stimulation and the severity of muscle tension in the head. Scientists have also established that severe muscle tension is linked to a lowering of the pain threshold, meaning pain is felt more easily and intensely. Inflammation and poorer blood circulation in the affected areas contributes to the problem.

2. Trigger points

A trigger point is a highly sensitive spot closely connected to the underlying muscles and surrounding connective tissue (known as “fascia”, hence the term “myofascial” trigger points). Pressing or stretching these points triggers pain. Such trigger points have been identified in many areas of the head and neck muscles. In chronic tension headache sufferers, activation of these trigger points is associated with very severe and prolonged head pain. Researchers are exploring potential treatments targeting these points.

3. Increased pain sensitivity

The frequency and intensity of tension headaches also has to do with an overall heightened sensitivity of the nerves in the head area, known as “sensitization” (from the Latin “sensibilis”, meaning “perceptible”). A key role is played by the trigeminal nerve, which is important for supplying sensations to a large part of the head. This nerve can both increase the excitability of pain-processing nerves and also be involved in the reduction of pain suppression. This in turn can lead to increased muscle tension, creating a vicious cycle.

The restructured brain: tension headaches have visible consequences

Tension-type headaches affect the structure of certain parts of the brain. This has been demonstrated by imaging techniques such as magnetic resonance imaging (MRI). The changes in brain structures mainly seem to affect the “gray matter” of the brain. Gray matter is located in the outermost layer of the brain and consists mainly of the cell bodies of neurons. Parts of the gray matter are involved in pain processing. A reduction in the size of these areas has been seen in imaging studies. The extent of this shrinkage was found to be directly linked to the duration of headache attacks. The changes were particularly marked in people with chronic tension-type headache.

The authors of the scientific publication suggest that prolonged activation of the areas involved in sensitization may lead to these structural brain alterations. More recent studies confirm that the strain on certain parts of the brain caused by constant heavy bombardment with pain signals not only alters volume distribution but also affects the structure of the affected regions.

Self-help strategies

Without a doubt, there are some pain attacks where short-term use of painkillers makes sense and is justified. However, any painkiller use should always be supervised and monitored by a doctor. This is the only sure way to avoid medication-overuse headache. Taken correctly, pain medication and migraine remedies do provide short-term pain relief; but they do not address the root causes. They are never a long-term solution to the problem.

A personalized approach is necessary to address the root causes of headaches. Lifestyle factors are crucial. Stress levels and individual response to stress play a huge role in tension headaches. Effective stress management is a key way to prevent tension headaches. Improving your individual stress coping skills is a good place to start, with professional support if necessary. Cognitive behavioral therapy teaches tools and exercises for a healthier way to handle stress.

One well-studied and effective way to significantly reduce the risk of headache attacks is through the use of relaxation techniques. Among these, Jacobson’s progressive muscle relaxation (PMR), a long-standing and well-established method in headache treatment. It is easy to learn and integrate into daily life. A handy ten-minute version is available in the app and on this website. Physiotherapy, including targeted massage and exercises to release tension in the head and neck, is another way to help prevent tension headaches. Regular physical activity is important too, and a good way to relax. Light endurance training outdoors is particularly effective for tension headaches.

The app can be a great tool to help you understand your own headaches and implement behavioral prevention strategies. It helps identify connections between personal behavior and the occurrence of headaches, making it easier to adopt a ‘head-friendly’ daily routine that you can stick to.