Although they are more common in children, nightmares can occur at any age. If you have occasional bad dreams, there is nothing to worry about, but if they occur frequently and prevent you from fully resting, they could be a sign that something is wrong with your body.

British Experts explain that nightmares can be triggered by many factors, including some illnesses.

According to the professionals, a stomach ulcer, for example, is capable of causing bad dreams.

An ulcer is an inflammation, damages to the gastric mucosa, therefore, it causes a certain pain. All this leads to increased stress, a feeling of discomfort, a feeling of pain, which can be exacerbated at night. This can stimulate nightmares, according to the experts interviews by Revyuh.

In addition to stomach ulcers, another condition that can lead to sleep problems is called restless leg syndrome. This disorder is characterized by pain or unpleasant sensations in the lower limbs, often at night. The uncontrollable urge to move when you are resting could result in bad dreams. Experts recommend seeking the help of a neurologist in these cases.

The doctors also noted that overeating before bed could lead to nightmares. Thus, they recommended avoiding eating three or four hours before sleeping.

While there is no consensus in the medical community on this issue, it is known that medical conditions that cause one to wake up in the middle of the night can potentially lead to a better recollection of dreams, including disturbing ones. Nighttime feeding can disrupt sleep in a number of ways, making a person more likely to remember their nightmares better if they eat before bed, Harvard Medical School noted.

Experts also pointed out that the use of some medications, including certain antidepressants and blood pressure drugs, can trigger nightmares in adults. The consumption of alcohol and recreational drugs or abstinence from these substances may also be the reason behind the frequent bad dreams, said Mayo Clinic.

The doctors pointed out, however, that the main cause of nightmares is stress. Oftentimes, the worries of daily life, such as a problem at home or at work, can affect dreams. A major change, such as a move or the death of a loved one, can have the same effect. 

In the case of frequent nightmares caused by reasons like these, it is recommended to seek the help of a psychologist.