Recurring nightmares could be a warning of serious health issues, expert warns

Most of us experience a nightmare occasionally: we might experience the frustration of running behind schedule, the humiliation of appearing naked in public, or fleeing from some otherworldly threat while we sleep.

On average, we undergo four or five cycles of dream activity during the night, with each dream spanning between 15 and 40 minutes. However, typically these dreams – whether pleasant or unpleasant – are forgotten shortly after awakening.

Numerous “classic” nightmares, such as falling or abruptly losing your teeth, are indicators of your brain processing concerns in your actual life – for instance insecurity, or anxiety about losing sexual potency – and are nothing to genuinely fret about.

Science communicator Jorge Alcalde suggests that if you observe the same nightmares returning repeatedly that could be grounds for concern.

Speaking on Spanish radio show Herrera en COPE, Jorge says that recurrent nightmares could be a warning sign: “A person who feels overwhelmed by frequent nightmares should report them, because it might indicate an underlying emotional issue, anxiety, stress, or depression,” he explained.

Abidemi Otaiku, MD, Clinical Research Fellow at the UK Dementia Research Institute told the European Academy of Neurology (EAN) Congress in 2025 that regular nightmares could be a warning of significant health issues.

In what he described as the first major study of its kind, Otaiku and his team found that adults who suffer weekly nightmares were more than three times as likely to die before the age of 75. That’s compared to those who rarely or never have to wake up from those bad dreams.

Repeated nightmares have been connected to conditions including post-traumatic stress disorder (PTSD), with 80% of PTSD patients experiencing them. They are also heavily linked with depression and anxiety disorders.

Other sleep disruptions, including sleepwalking and restless leg syndrome, can likewise indicate some underlying problem, Jorge cautions.

Amongst the most severe and alarming sleep disturbances is sleep paralysis. One of the body’s “safety mechanism” is a state of temporary paralysis, known as REM atonia, which prevents the sleeper from moving while they’re dreaming. But in certain rare situations, a person can wake up before that paralysis fades away. The experience can be terrifying, and is thought to be the cause of supernatural experiences such as hauntings and alien abduction.

Jorge explains that this experience is often accompanied by hallucinations because “your consciousness is not yet fully activated.” The relationship between parasomnias, or sleep disorders, and neurological conditions such as Parkinson’s and Alzheimer’s represents a significant area of medical investigation at present. Currently, debate focuses on whether parasomnias are a cause or consequence of these conditions. “It is known, for example, that Parkinson’s increases the likelihood of unusual behaviours in the body during sleep,” Jorge said.

He further noted that the occasional nightmare is nothing to be concerned about, stressing that the last thing he wished to do was alarm those prone to health anxiety. He emphasised that there is no scientific certainty that occasional sleep disturbances share an explicit connection with disease – unlike, for instance, a blood test: “Nightmares are not a symptom of illness,” he stressed, but rather a potential indicator that something could be improved within one’s emotional wellbeing.

A heightened frequency of nightmares is linked to heart disease, as they can trigger waking with a racing heart and elevated blood pressure. They have additionally been associated with sleep apnoea, whereby the brain may generate nightmares of choking or drowning as a result of restricted oxygen supply.