It’s estimated that 70% of adults experience at least one bad dream per month, and 5% of adults develop a nightmare disorder during their lifetime.
Despite their prevalence, scientists have struggled to agree on the exact causes of bad dreams and nightmares. Thankfully, there are many ways you can reduce their impact. In addition, they may even have a purpose which you can exploit to your advantage.
Bad Dreams and Nightmares in Adulthood
It’s important to determine the differences between bad dreams, nightmares and night terrors. These unique sleep experiences occur at different stages of the sleep cycle and are thought to have different causes. Crucially, each one responds to a different type of treatment.
What is a Nightmare?
A nightmare is a negative sleep experience that causes you to wake with a fright. Nightmares are intensely vivid experiences. For the first few seconds after waking, you may be unsure whether your experience was real or imagined.
Nightmares tend to occur during REM sleep. Throughout the night, we enter periods of REM sleep which last for around 90 minutes each. Overall, adults spend about 25% of the night in REM sleep. Babies are thought to spend about 80% of their sleeping time in REM sleep – a figure which gradually reduces over the lifetime. This is why children have many more nightmares than adults.
During REM sleep, brain waves are altered to mimic those involved in concentration. Scientists predict that nightmares may be caused by the excessive brain activity that occurs during periods of REM sleep – compared to other periods of sleep.
Because nightmares cause you to wake up, they can disrupt sleep and lead to a sleeping disorder. The occasional nightmare is unlikely to affect overall sleep health, but it can be an intensely disturbing experience. Below we’ll discuss the potential causes of nightmares and how they can be prevented.
What Are Bad Dreams?
Bad dreams are much more common than nightmares. Over the course of a month, it’s thought that the average person will have at least one bad dream. Unlike nightmares, bad dreams don’t cause you to wake up during the night. In the morning, you may wake up with a sense of unease, confusion – or maybe just relief that it was only a bad dream!
Bad dreams are usually not as vivid as nightmares. Often, people know they’ve had a bad dream, but they find it hard to remember exactly what happened. Sleep scientists have argued that bad dreams can be more disturbing in the long-term because some people spend a lot of time anxiously trying to recall and ‘make sense’ of their bad dreams. For example, you’re trying to make sense of a dream about a person.
According to sleep specialists, there are four ‘stages’ of sleep. Nightmares and bad dreams occur during stage three of sleep. Nightmares occur during the ‘REM cycle’ of stage three sleep, whereas bad dreams occur during the ‘non-REM cycle’ of stage three sleep. During the ‘non-REM cycle’ of stage three sleep, you’ll be sleeping very deeply, and your muscles will be very relaxed.
Are Night Terrors the Same As Nightmares?
Night terrors are different from both nightmares and bad dreams. They typically occur during stage four of sleep and can cause significant distress to others sleeping in the same household. People with night terrors wake up screaming and sweating. They may not be fully ‘awake’ during this period, so family members trying to comfort them may find it hard to engage with them.
Night terrors are not thought to be caused by nightmares or bad dreams. Although they are intense emotional experiences, sufferers usually have no explanation or ‘storyline’ for them and may not recall them at all in the morning. They are more common in teenagers. This is because they occur during stage 4 of sleep – a stage very important for hormonal development.
Common Nightmares and Bad Dreams
Bad dreams will usually feature a ‘threat’ of some sort. This could be a threat towards your health, self-esteem, beliefs, relationships, or your life. It’s common for bad dreams to be both frightening and absurd at the same time. After waking from a bad dream, you’ll often feel that the dream would never happen in real life. However, this realization doesn’t necessarily dampen the unnerving effects of the dream.
Scientists have studied the content of bad dreams and nightmares. According to a recent study, common themes include:
- Physical Aggression (sometimes leading to death)
- Interpersonal Conflicts (i.e. with family, friends, and coworkers)
- Health concerns and Death
- Being Chased or Stalked (very common!)
- Supernatural or Evil Forces
- Drowning or Falling
- Natural Disasters
All of the above can feature. However, a study conducted by Oxford Sleep Research Society found that physical aggression tends to feature more frequently in nightmares. Bad dreams are much more likely to feature interpersonal conflicts, such as fights with family and friends. Bad dreams are also more likely to feature ridicule and threats to self-esteem, such as losing one’s job, failing at something, or being publicly shamed.
‘Fear’ is the most common emotional experience – in both nightmares and bad dreams. However, it has been found that bad dreams tend to incite a wide range of secondary emotions, including sadness, guilt, remorse, disgust, and confusion.
Bad dreams are more common than nightmares, they tend to last for longer (because they don’t wake us up), they usually have a complex storyline to them, and they lead to a wide range of emotions. This might suggest that bad dreams reveal something more fundamental about our psychological and emotional states than nightmares do.
Why Do I keep Having Bad Dreams and Nightmares?
In many cases, nightmares are spontaneous and idiopathic (i.e. their true cause is unknown). Nonetheless, many sleep scientists agree that our physical and psychological health have an impact on our dreams.
Below we’ll discuss the potential causes of nightmares and bad dreams. Many of the ‘causes’ impact bad dreams indirectly because they influence health, well-being, and sleep quality.
War veterans, abuse survivors, and anyone who has suffered from a highly traumatic experience may develop a condition called Post Traumatic Stress Disorder (PTSD). As part of this condition, they’ll experience flashbacks of their painful experiences.
Prior to receiving treatment, it’s common for individuals with PTSD to experience nightmares every night. Nightmares may involve a reenactment of the traumatic experience or may focus on wider themes such as ‘ridicule’ and ‘shame.’
Individuals who have suffered an upsetting experience, but who have not developed PTSD, are also likely to dream about their upsetting experiences. These bad dreams may be sporadic or recurring. In some cases, they can arise years after the original event.
If you suffer from recurring nightmares, it’s worth analyzing the content of the dreams to determine whether there may be a post-traumatic element to them.
Weird Dreams During Pregnancy
Many mothers-to-be experience vivid and intense dreams during pregnancy. This phenomenon appears to be more common in first-time mothers, in the third trimester of their pregnancy.
It’s thought that the shift in hormones may be responsible for causing strange or unnerving dreams during pregnancy. Others argue that, because pregnancy is a stressful time, the associated stress of the pregnancy may be causing bad dreams to occur (more on stress below!)
Finally, because pregnant women are more likely to wake up frequently throughout the night – particularly during the third trimester – they’re probably better able to recall their dreams. As such, they may perceive their dreams to be more vivid and disturbing simply because they’ve been woken up in the midst of one.
Sleep Deprivation and Bad Dreams
Sleep deprivation could be a cause of bad dreams, an effect of bad dreams (or both!)
Scientists agree that, because sleep deprivation has a negative impact on health and sleep quality, it’s likely that it could influence bad dreams. As mentioned, ‘Sleeping-through’ the whole night without waking is known to decrease the perceived potency of bad dreams – because people are less likely to recall bad dreams if they don’t wake up during the night.
As such, anything that threatens sleep quality is likely to increase the impact of bad dreams.
Can Food Cause Nightmares?
It’s a commonly held belief that eating cheese causes vivid dreams and nightmares. However, there is very little clinical evidence to support this claim! Studies suggest it is our eating habits (rather than our food choices) which impact nightmares and bad dreams.
There is evidence to suggest that going to bed very hungry can induce vivid dreams. Having said that, eating a meal too close to bedtime can speed up the body’s metabolism, signaling the brain to remain active long into the night. As such, it’s advisable to find a good balance between the two – to protect against nightmares.
Drinking caffeine late at night may also cause bad dreams because it may interfere with brain activity. However, there is currently little evidence to support this claim. Eating a healthy balanced diet that is not too reliant on carbohydrates and sugars will keep your mood stable. Some scientists argue that this can protect against an array of sleep disorders – including nightmare disorder.
Exercise and Bad Dreams
Exercise is necessary for good quality sleep, so exercise may help prevent bad dreams from occurring. One study found that, when individuals exercised in the morning, they were better able to fall asleep and reported having fewer nightmares.
Runners or endurance athletes spend less time in dreamy REM sleep. This means that, potentially, they are less likely to be disturbed by bad dreams and nightmares because these occur during the REM cycle.
Does Stress Cause Bad Dreams?
Many studies from the 1990’s found that having a neurotic personality meant you’d be much more likely to experience nightmares. More recently, studies have found stress and anxiety to be more common in people who experience bad dreams and nightmares.
Scientists aren’t exactly sure whether it’s stress that is causing nightmares, nightmares that are causing stress, or whether the two are linked because of another reason. For example, the anti-depressant drugs used in the treatment of anxiety can sometimes cause nightmares.
Most would agree that stress and anxiety, at the very least, have an indirect effect on dreaming because stress affects sleep quality.
TV and Nightmares
It might seem obvious, but the activities we engage in directly before sleep can have an impact on our dreams.
Studies have shown that the content of people’s dreams is often determined by the things they watch on TV, the books they read, and the conversations they have with others. Often, bad dreams are a mish-mash of the above. Some sleep therapists recommend limiting TV and video games in the evening to try and reduce bad dreams.
What Is the Meaning of a Bad Dream?
According to Freud, dreams reveal the content of our unconscious mind (or our true selves).
By analyzing the content of our dreams and nightmares, we may become aware of the things we should correct in our lives. Like Freud, some psychologists have continued to focus on the ‘symbolic’ functions of dreams, whereas others have attempted to redefine the purpose of dreams.
Depending on who you ask, bad dreams may have one (or more) of the following functions:
- Creativity – During our waking hours, creativity is inhibited by a number of physical and moral factors. Some psychologists argue that dreams (including nightmares) function as a pure and uninhibited expression of creativity. It has been said that Mary Shelley’s Frankenstein was first experienced in the form of a nightmare.
- Memory – The phrase ‘Let me sleep on it!’ suggests that sleep is helpful for processing and cementing new information. Some psychologists have argued that dreams play a role in helping us sort through, remember and store information.
- Fight or Flight Mechanism – The fight or flight mechanism is our body’s natural instinct to either fight or to run away from a threat. During REM sleep cycles, brain waves mimic the waking state, so the brain is on high alert. A part of the brain called the Amygdala (responsible for the body’s fight or flight mechanism) is also highly activated.
It’s thought that this highly aroused state can induce nightmares because our body thinks it’s in fight or flight mode. In theory, REM sleep becomes a type of ‘training’ for how to effectively deal with threats in the real world.
- Symbolism and Therapy – As mentioned, Freud popularized the idea that dreams held meaning – and thus could be used for personal development. As humans, we like to solve problems and seek out the meaning. As such, many people are comfortable with the suggestion that dreams are symbolic of our inner psyche.
Analyzing our nightmares can be a therapeutic process because it prompts us to reevaluate our lives. For example, drowning is a very common nightmare, which is believed to symbolize a ‘loss of control.’ Some argue that, because our waking lives feature so many competing demands, we are not always able to determine the ‘sticking points’ in our lives. As such, the function of nightmares may be to provide us with constructive ‘awakenings’ to our problems.
How to Stop Bad Dreams
Bad dreams can be tackled directly or indirectly. Indirect treatment methods focus on improving the quality of sleep. Sleeping peacefully means we are less likely to wake throughout the night – therefore, we are less likely to recall our bad dreams. Direct treatments involve ‘cognitive restructuring’ techniques which focus on ‘reframing’ bad dreams and nightmares to reduce their frequency and impact.
- Take Regular Exercise – Ideally in the morning
- Reduce Stress –Practice Yoga, meditation or mindfulness
- ‘Strike a Balance’ with Evening meals – Do not overeat near bedtime, but do not sleep hungry
- Improve Sleep Hygiene – Try to establish a healthy bedtime routine
- Reduce Intake of Alcohol
- Do Not Take Recreational Drugs
Desensitization Therapy for Bad Dreams
This intervention is borrowed from the field of Cognitive Behavior Therapy – a group of therapies that encourage individuals to form healthier cognitions and behaviors. Essentially, it works by exposing the individual to their fears (i.e. the content of their bad dreams) so that they become desensitized to the stimuli. Desensitization works best for recurring nightmares or recurring bad dreams.
- If someone had a recurring nightmare about spiders, the therapist would encourage them to gradually face their fear. When the content of the dream is more abstract, the therapist and patient may have to work harder to try and understand which fears need tackling.
- If someone frequently had nightmares about being publicly ridiculed, this might suggest they harbor an intense fear of criticism and rejection. Desensitization therapy may involve that individual intentionally subjecting themselves to criticism. For example, the therapist might ask the patient to send an email to their boss that is full of typos or to say something controversial to a group of strangers. This should encourage the individual to see that criticism is not such a scary thing.
Desensitization theory dampens the potency of nightmares. Eventually, the ‘nightmares’ are no longer nightmares because they are no longer frightening. A recent review published on NCBI found that desensitization therapy is a highly effective treatment for managing recurring bad dreams.
Image and Rehearsal Therapy for Nightmares
Image and Rehearsal Therapy helps PTSD sufferers sleep better, by reducing the emotional impact of nightmares. In fact, it’s a useful technique for anyone who experiences recurring nightmares. It works by encouraging people to ‘re-write’ the script of their nightmares.
Sufferers begin by writing down the details of their nightmares. Then, with the help of a therapist or friend, they’ll re-write a less frightening and more empowering version of the nightmare. For example, if someone constantly dreams of being attacked, they might focus on how they would defend themselves from an attack and incorporate this into the script of the dream.
Once the ‘new’ script has been visualized and rehearsed during waking hours, sufferers are more likely to dream about the new ‘script’ during sleep. In the long term, this helps PTSD suffers take control of their flashbacks and nightmares.
How Do Nightmares Affect the Body?
Nightmares and bad dreams can negatively affect the body in three main ways:
- Sleep Disturbances – It can be very difficult to get back to sleep after experiencing a nightmare. If nightmares continue on a regular basis, this could lead to a sleep disorder. If nightmares are particularly vivid and disturbing, going to sleep can become a frightening prospect. As such, people suffering from recurring nightmares tend to delay their bedtime until late in the night. Ultimately, this can cause fatigue and insomnia.
- Mood Disorders – Although mood disorders (i.e. anxiety and depression) may be a cause of nightmares, some studies have suggested that nightmares may cause mood disorders. Scientists predict this may occur because recurring nightmares cause intense frustration and helplessness– which may lead to the development of a mood disorder.
- Health Behavior Problems: Some people turn to alcohol or drugs to deal with nightmares or sleep problems. This is an issue because it obscures the original diagnosis and prevents nightmare disorders being treated effectively.
Some people argue that occasional bad dreams and nightmares can be useful for the body and mind, because they may inspire us to tackle our worries and problems.
How to Recover from a Bad Dream or Nightmare
If a nightmare has woken you up and you’re finding it hard to get back to sleep, don’t try to force yourself back to sleep as this can lead to frustration. Instead, turn your attention to another activity until you feel tired enough to sleep again.
Some people find that talking to a friend helps them make sense of a bad dream. Alternatively, others find it therapeutic to write down the contents of their dreams. Taking note of your bad dreams can be useful for trying to identify any triggers.
As mentioned, it’s possible to see dreams as ‘therapeutic awakenings’, so consider whether the content of your bad dream has inspired you to take any positive action.
It’s worth remembering that around 5% of the population suffer from a diagnosed nightmare disorder. If nightmares are negatively impacting your life, and you don’t feel able to manage them yourself, it’s advisable to see a professional for further guidance.