About paranoia

Information about paranoid thoughts and paranoia

It sometimes seems as if the one thing that unites the diverse peoples of the world is our fear of one another. Worries about other people are so common that they seem to be an essential – if unwelcome – part of what it means to be human.

The focus of this website is not on justified anxieties about others, but rather on exaggerated or unfounded fears – fears for which there is little or no convincing evidence. Exaggerated worries about others don’t help us stay safe but instead can bring all manner of distress.

What is paranoia?

We could have called this section: What are fears about others? We could also have titled it: What are paranoid feelings? Or: What are persecutory beliefs?

Some people use the terms delusional thoughts or, for severe instances, persecutory delusions. The feelings discussed in this website, then, go by a variety of names. Partly this is because paranoia is a term that covers a wide spectrum of experiences. What we mean is:

  • The fear of something bad happening
  • The idea that others may intend to cause such an event
  • The thought is exagerrated or unfounded.

These fears normally contain certain elements: a perpetrator, a type of threat, and a reason. We can suspect absolutely anyone of wanting to do us harm. Often the perpetrator is a neighbour, stranger, work colleague or family member. Occasionally it may be government organisations or spirits. Sometimes the identity of the person trying to cause the harm is unknown. The type of harm varies too. But typically the fear is of physical, psychological, social or financial harm. Why do people think others are targeting them for harm? Sometimes there’s a feeling of simply being a victim, sometimes it is suspected that we’re at risk because of who we are, and sometimes it because we think the threat is provoked by something we’ve done.

How common is paranoia?

UK adults surveyed


adults have felt that people are against them


have felt controlled by outside forces


have believed that people wish them harm

Until very recently – the last 15 to 20 years in fact – no one suspected just how many people had paranoid thoughts.

But several research projects have now lifted the lid – and the results are striking. Here are just a few statistics from some of those research projects.

  • In a survey of 8580 UK adults, 21% said there’d been times over the past year when they’d felt people were against them. 9% said they’d believed that their thoughts were being controlled or interfered with by some outside force or person. 1.5% said there’d been times when they’d felt people were plotting to cause them serious harm.
  • A study of 1005 adults in New York found that 10.6% believed other people were following or spying on them. 6.9% thought people were plotting against them, or trying to poison them. 4.6% believed people were either secretly testing them, or experimenting upon them.
  • A French survey of 462 adults found that 25% had, at some point in their lives, felt that they were being persecuted in some way. 10.4% had sometimes believed there was a conspiracy against them.
  • A study of 1202 British university students (aged 16 to 61) assessed their feelings over the previous month. 42% said that, at least once a week, they had thought that negative comments about them might be circulating. 27% had felt that people were deliberately trying to irritate them, and 19% had thought that they might be being observed or followed. 5% thought there might be a conspiracy against them.
  • More than a thousand older adults (aged 55 and above) in Brooklyn, New York were assessed. 13% had, in the previous week, experienced paranoid thoughts.
  • Paranoia, then, is widespread – so widespread, in fact, that around 15 to 20% of the population have frequent paranoid thoughts. Most of those people aren’t much troubled by their suspicious thoughts. But a further 3 to 5 % have pretty severe paranoia. For this smaller group of people, their paranoia is often serious enough to need specialist treatment.

What are the causes of paranoia?

Research has identified five main factors involved in the occurrence of suspicious thoughts.

All five factors are very common – all of us will have experienced at least some of them. What’s important though is the way they combine. Suspicious thoughts are caused by a combination of some or all of these five factors:

  • Stress and major life changes. This includes difficult relationships with others at home or at work, and becoming isolated.
  • Negative emotions such as anxiety and depression. Often when we are anxious we can overestimate the chances of threat and worry too much. The way we feel has a big influence on the way we think.
  • Internal unusual feelings. Stress can often cause strange feelings (eg. feeling odd, aroused, threatened), as can going without sleep. Sometimes people can feel odd because they have taken drugs such as cannabis.
  • Our explanations. Paranoid thoughts are our way of trying to understand things. They are attempts to make sense of events. It’s perfectly natural to try to understand the world around us – and the way we feel inside. But when we’re stressed and feeling low or anxious or irritable our explanations are likely to be pretty negative. We think the worst – and often we think the worst of people around us. It can seem as if the odd or unpleasant things we’ve been experiencing are deliberately caused by other people.
  • Reasoning (the way we think things through and come to decisions and judgements). Often suspicious thoughts can take a grip if we do not think of alternative explanations for events, and do not fully consider the evidence for and against our worries. This is sometimes called jumping to conclusions.
  • So, when we are stressed and things are perhaps not going too well, we can become anxious and interpret how we feel in terms of threat from other people, without fully weighing the evidence or considering alternative explanations.

How can we tell whether our suspicious thoughts are justified?

How can we tell whether our worries are justified or not? Well, it’s not always easy.

If you’re struggling to decide whether your suspicious thoughts are justified, ask yourself the following questions:

  1. Would other people think my suspicions are realistic?
  2. What would my best friend say?
  3. Have I talked to others about my worries?
  4. Is it possible that I have exaggerated the threat?
  5. Is there any indisputable evidence for my suspicions?
  6. Are my worries based on ambiguous events?
  7. Are my worries based on my feelings rather than indisputable evidence?
  8. Is it very likely that I would be singled out above anyone else?
  9. Is there any evidence that runs contrary to my suspicions?
  10. Is it possible that I’m being at all over-sensitive?
  11. Do my suspicions persist despite reassurance from others that they are unfounded?

There are no hard and fast rules for deciding for certain whether a worry is realistic. But by asking yourself these questions you can determine the probability of the suspicion being justified.

The probability that your fears are unrealistic increases the more you feel that:

  • No one else fully shares your suspicions
  • There is no indisputable evidence to support your worries
  • There is evidence against your suspicions
  • It is unlikely that you would be singled out
  • Your fears persist despite reassurance from others
  • Your fears are based on feelings and ambiguous events