There are more than 300 headache causes. These are the most common ones.

Nearly all of us have experienced the pain and inconvenience of having a headache. The dull ache can make it difficult to concentrate and cause even simple tasks to feel unmanageable. Whether the pain hits you as soon as you wake up in the morning, in the middle of your workday, while you're trying to enjoy time with family or friends, or as a result of drinking too much the night before, headaches are a universally understood sensation that many people can relate to. 

But it surprises some to learn that headaches can be brought on or caused by literally hundreds of factors and that different types of headaches last much longer than others.

What is a headache exactly?

While headaches can be felt differently by different people, the general definition of a headache is any pain or discomfort felt in one's head or around the front of one's face. It's one of the most common sensations that affects adults, teens, and children alike. Cleveland Clinic estimates that about 96% of people will experience a headache at least once in their life; and many of us will experience them more regularly than that. 

Though we frequently refer to any pain in our head as a headache, it isn't its own diagnosis, but is instead a symptom of a broader issue. "Headache is a general term that covers the very many ways one can have pain in the head such as being hit in the head, an infection, or a brain tumor," explains Peter Goadsby, a professor of neurology at King’s College London.

What causes headaches? 

These are far from the only causes or contributing factors in experiencing a headache, however. "There are over 300 different causes of headache," says Rashmi Halker-Singh, a neurologist and director of the headache medicine fellowship program at Mayo Clinic in Arizona.

Some of the most common causes include alcohol consumption, genetic factors, diet, medications, hormones, dental issues, sickness and allergies. "Stress is the most common trigger of tension-type headaches," says Alexander Mauskop, director and founder of the New York Headache Center in Manhattan. Tension-type headaches are the most common type of headache. It's usually experienced as a dull ache on both sides of one's head or feels like a tight band around one's forehead. 

Stress contributes to this type of headache especially because one's brain releases certain chemicals during times of emotional stress. These chemicals can result in vascular changes in the brain and are experienced as pain. Stress also impacts the quality of one's sleep, and lack of sleep is another significant cause of headaches. Tension-type headaches can also be caused by shoulder muscles trying to compensate for poor posture. 

Headaches can also be symptoms of many diseases or conditions such as heart disease, growths or tumors and epilepsy. 

Catherine Kreatsoulas, PhD, an instructor at Harvard T.H. Chan School of Public Health, has participated in research showing that past trauma can also cause recurring headaches. "My team and I uncovered that people who had experienced one or more traumatic childhood events were 48% more likely to have headache disorders in adulthood than those who had not experienced such a traumatic event," she says. 

How long do headaches usually last? 

Durations of headaches differ across headache type or cause, but Mauskop says that tension-type headaches usually end "within hours or a day." The pain can return again quickly, however, if the underlying cause isn't addressed. For example, The National Headache Foundation notes that unless chronic or repeated stress is managed, stress can cause tension-type headaches every day. 

Goadsby says that cluster headaches - a very painful type of headache that tends to be felt only on one side of the head, "typically last from 30 to 180 minutes." Headaches that occur as a symptom of chronic diseases or serious injury may come and go more often. "A concussion can cause headaches that persist for months and even years," says Mauskop.

In most cases, however, Dr. Amaal Starling, an associate professor of neurology at Mayo Clinic in Arizona, says that headaches will go away on their own. "If any treatment is needed," she adds. "Many over-the-counter medications can be easily effective." 

More:A migraine is more than just a bad headache. Here's what causes them.