Much of the anxiety in my life has emerged from the question what if. What if my headache has a more sinister origin? What if I go to a holiday party, and don’t know anyone? What if I publish an article, and everyone hates it? I want to be certain of what’s going to happen, and any uncertainty makes me squirm. In other words, I have an intolerance for uncertainty. Each day, we face uncertainty around our health, what others think of us, our career, or what soup will be served at lunch. Yet some people recoil at these unknowns more than others. Since the early 1990s, psychologists have isolated intolerance for uncertainty, or IU, as a trait associated with different forms of anxiety, depression and substance use disorder. IU doesn’t directly cause all of those conditions, but having a higher intolerance for uncertainty is a common experience that cuts across them. IU works in a similar way to, say, a food intolerance. When some people eat a small amount of dairy, their stomach is upset. Others can finish a bowl of mac and cheese and feel fine. With uncertainty it’s the same: some people are just more sensitive to it. Here’s how to tell if your intolerance for uncertainty is high, and what you can do about it. How the intolerance of uncertainty scale works IU exists on a spectrum; it’s not that everyone is either totally intolerant of uncertainty or completely OK with it. Some may be mildly put out by uncertainty, while others have an average intolerance, said Naomi Koerner, an associate professor of psychology at Ryerson University. “And some other people are highly bothered by the uncertainties of life.” IU was defined as a specific trait in the 1990s by the researchers Mark Freeston, Michel Dugas and others at Laval University in Quebec. They were trying to understand the underpinnings of generalized anxiety disorder and excessive worry. Freeston said they developed the Intolerance for Uncertainty Scale on a hunch that there was a cognitive signature of those experiences. The scale asked people how much they agreed with phrases such as: “I should be able to organize everything in advance,” “I always want to know what the future has in store for me,” and “Uncertainty makes life intolerable.” How intolerance of uncertainty affects our mental health Too much unknown leads to some stress for nearly everyone. “Most people score in the middle for IU based on self report,” said Jayne Morriss, a lecturer in the School of Psychology at University of Southampton. Being intolerant of uncertainty can be helpful for survival, said Brady Nelson, an associate professor of clinical psychology at Stony Brook University. “It keeps us attentive and alert in uncertain and unfamiliar environments that could be associated with danger or threat,” he said. But when intolerance becomes very frequent, and a dominant part of how you interact with the world, it can lead to anxiety, worry and avoidance. People who score highly on the scale are bothered by even minor cases of uncertainty. It makes them stressed, irritable or anxious, and they are motivated to avoid it at all costs, or control their environments to reduce uncertainty as much as possible. According to Koerner, this can manifest in overplanning, not allowing spontaneity, repeated reassurance or information-seeking, and avoiding anything new or unfamiliar. Someone with high IU might make lists repeatedly, plan out conversations in their head, look at food menus before going to a restaurant or triple-check their driving routes. People with a higher intolerance can also react to events more impulsively, in order to resolve uncertainty as quickly as possible. For people with high levels of the trait, uncertainty is not just unpleasant, Koerner said: “It is more like, ‘I cannot stand it, I cannot cope with it.’” There are many kinds of uncertainty Uncertainty is not just one thing. Sometimes you don’t know what’s going to happen, but you are aware you’re going to encounter uncertainty. In other situations, you might not expect the unknown at all. Uncertainty can take place in the external world, like an uncertain outcome, or inside of us, like feeling uncertain. Researchers are teasing apart these differences now. Some people are more upset by prospective IU, or the anticipation of uncertainty. Others have higher inhibitory IU, meaning they freeze or can’t act when experiencing uncertainty. “Both types of individuals will tell you they dislike uncertainty, but the way they process and react to the uncertainty might differ a lot,” Nelson said. So far, research has mostly focused on how IU manifests in an individual, but there are probably systemic factors that make people more sensitive to uncertainty, like money scarcity, exposure to conflict or discrimination. This intolerance might apply to positive outcomes too. For instance, a person with higher IU would rather have a planned birthday party than a surprise birthday party, even if the surprise party could be more fun. People with higher IU and generalized anxiety disorder symptoms have been shown to dampen their positive emotions and savor their experiences less, and to think that situations with potentially positive outcomes have more threats attached to them. How to make peace with uncertainty People with mental health conditions who are interested in building their tolerance of uncertainty can work with a therapist to directly strengthen that, rather than examining or analyzing the content of their worries, Nelson said. In 2016, I was diagnosed with obsessive compulsive disorder, a condition that is often paired with a high intolerance for uncertainty. In OCD treatment, which involved exposure therapy, I confronted my anxieties and learned how to better handle not knowing exactly what would happen. Instead of homing in on any one specific health anxiety, for example, I could instead confront my uncertainty of whether I’ll become ill one day. Because IU is associated with many mental health conditions, treating it could help with any or all of them, Nelson hopes. “Rather than attempting to treat multiple distinct mental health conditions, it might be more effective to focus treatment on increasing tolerance of uncertainty, which might alleviate multiple co-occurring problems,” he said. For milder discomfort with uncertainty that doesn’t cause significant distress or disruption to your life, you can build your own tolerance to uncertainty a little bit each day. Seek out opportunities to safely play around the edges of your routines. “For example, if you always do things in the same order, do the same familiar things, but in a different order,” Freeston said. If you go on the same walk each morning, flip the route and do it in the reverse direction. After experimenting with small exposures to uncertainty, challenge yourself to do other new things – nothing “big or scary, just things that are different and will initially feel uncomfortable”, Freeston said. “Over time, people can learn to tolerate uncertainty, and even accept and perhaps embrace the uncertainties in day-to-day life.” Life will always be full of unknowns. When facing the uncertain, you might feel discomfort, but there’s also a chance to try to feel curious and open. “Ask yourself, ‘What can I learn here?’” Koerner said. When we can find a way to be excited or intrigued by the unknown, rather than afraid, uncertainty becomes much more palatable.