Tension headaches: what causes them?

Tension headaches: what causes them? 

The headache type most people are familiar with – without knowing its name – is “tension-type headache” (known as “TTH” for short in the scientific community), or just “tension headache”. Tension headaches are the most widespread form of headache – but because they’re so common, people tend to dismiss them as an inevitable part of life. And yet, the very fact that tension headaches are so widespread means they should be taken seriously.

Are headaches normal?

Because headaches are widely considered ‘normal’, many people see no reason to consult a doctor for their headaches, even if they get them often. A common belief is that headaches are no big deal, they just come and go. As a result, most people self-diagnose and self-medicate without professional guidance. The truth is that different types of headache have different causes and require different treatments, making a proper medical diagnosis essential. What’s more, any use of painkillers should be under medical guidance and monitored closely. Improper medication can lead to “medication overuse headache”, a distressing condition requiring extensive treatment.

Tension-type headaches are widespread

Tension headaches are remarkably common. Among individuals aged 12 to 41, approximately 86% experience at least one episode per year. Studies suggest peak occurrence in the 30 to 39 age group. The prevalence declines with age. Globally, as many as 2 billion people may be affected, making tension-type headaches the third most common health condition worldwide.

The reported frequency of tension headaches varies from approximately once a week (10%) to several times a month (24–37%). A smaller percentage (2–3%) suffer from chronic tension headaches, sometimes alongside migraines. Chronic tension headaches – defined as more than 15 episodes per month – are frequently associated with depression, mood disorders, and anxiety. Most sufferers have episodic tension-type headaches with a maximum of 15 attacks per month, but even episodic cases can significantly impact daily life.

The understudied headache

Headache research is challenging due to the complex physiological processes involved. There are never any easy answers. The causes and correlations underlying the various types of headache are evolving continuously, with old hypotheses being revised all the time as new insights emerge. The pathophysiology of tension-type headaches has also been studied for a long time, and various explanations have been proposed.

Compared to migraines, another common headache type affecting around 15% of the population, tension headaches are more widespread, yet significantly less studied. One possible reason is that they are often dismissed as ‘everyday headaches’. However, they can be highly debilitating and impair quality of life, particularly when severe or chronic.

New findings on the causes of tension headaches

Leading researchers agree that multiple factors contribute to tension headaches. Environmental, i.e., external, influences play a key role. The main physiological mechanism is probably pain regulation. When pain regulation malfunctions, continuous pain-triggering signals may heighten sensitivity, causing harmless minor stimuli to be perceived as pain. This increased pain sensitivity increases the risk of chronic headaches.

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

1. Pericranial tension

Pericranial tension affects the pericranium, i.e., the connective tissue covering the skull bones. When certain pain receptors (nociceptors) around blood vessels, tendons, and connective tissue become overstimulated, muscle tension increases. Research has shown a direct link between the frequency and intensity of this stimulation and the severity of muscle tension in the head. Increased muscle tension is also known to lower pain thresholds, leading to inflammatory reactions and impaired blood circulation in the affected areas.

2. Myofascial trigger points

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

3. Central sensitization and increased pain sensitivity

The frequency and severity of tension headaches is influenced by overall nerve sensitivity in the head. 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. These effects of the trigeminal nerve on pain generation and perception in turn cause increased muscle tension, creating a vicious cycle.

The restructured brain: tension headaches have visible consequences

Tension-type headaches visibly affect brain structures, as demonstrated by imaging techniques such as magnetic resonance imaging (MRI). The structural changes 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 (perikarya) of neurons. Parts of the gray matter are involved in pain processing. A reduction in the volume of these areas has been seen in imaging studies. The extent of this shrinkage correlated with the duration of headache episodes. In chronic tension-type headache sufferers, these changes were particularly pronounced.

Researchers suggest that prolonged activation of the areas involved in central sensitization may lead to such changes. 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

Pain relief medications can be useful in managing acute headaches but should always be used under medical supervision. The frequency of medication use requires careful monitoring, in particular to avoid the risk of the condition known as medication-overuse headache. Taken correctly, pain medication and specific migraine remedies do provide short-term pain relief, but do not address the root causes. They are never a sustainable therapeutic 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 central role in tension headaches, making effective stress management essential in any tension headache prevention strategy. Improving your individual stress coping skills is a good place to start, with professional support if necessary. Cognitive behavioral therapy is one way to develop healthier mechanisms for coping with 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 well-established method in headache therapy – has proven particularly beneficial. It is easy to learn and integrate into daily life. A handy ten-minute version is available in the app and on the 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 help in understanding your own headaches and implementing 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.