Lying is a part of human nature. We’ve all lied, and we’ve all been lied to. Some people stick to white lies, while others experiment with large-scale fibs. It’s a simple truth that we’ll be exposed to a lie at some point during our lives, whether it involves ourselves or one of our acquaintances. None of us want to be the victim of a lie, which is why we devote so much energy to learning how to spot liars. We read books on lie detection, listen to TED talks from psychologists on the signs of lying, and scan Internet articles about the patterns of a liar in order to gain insight into the art of lying. You’re probably reading this list right now because you suspect someone of lying to you and want to find out if they are.

Unfortunately, there’s no easy answer to the question, “Am I being lied to?” There isn’t one magical sign that proves without a doubt that someone is lying. There are some behaviours that are common to liars, but they aren’t foolproof methods of lie detection. Like with physical lie detectors, there’s room for error; the key is to get to know a person well enough to be able to spot unusual changes in their behaviour. If a fluent speaker suddenly suffers a fit of the stutters, then that person might be in the middle of delivering a lie. Don’t assume that a person is lying to you if they exhibit any one of the signs on this list, but if several of these signs come to your attention, then you might want to fact check that person’s statements.

20. You observe a change in a person’s baseline behaviour

Not all liars are created equal. There isn’t one overt behaviour that’s common to all liars. Therefore, in order to tell if someone’s lying to you, you need to take a measure of that person’s baseline behaviour. Observe how that person behaves in situations where they’re telling the truth. Do they normally fidget, or is that an unusual behaviour for them? Do they always speak really fast, or only when talking to their boss? Being aware of what constitutes a person’s typical behaviour is important when pinpointing liars. If you witness a change in a person’s baseline behaviour, then that person may be lying to you.

19. You notice a person pulling their body inward

Pay close attention to a person’s body language when interacting with them. Body language can give us clues as to whether a person is being honest with us or lying to us. A person who suddenly shrinks into himself could be in the process of telling a lie. Liars often unconsciously try to make themselves appear smaller so as not to attract attention. That way, their lies will have a greater chance of going undetected. If you notice a person beginning to hunch over, or pulling their arms into their chest, then be on the alert for additional lying behaviours.

18. Your conversation partner comes down with a sudden case of rapid blinking

If you’re in the middle of swapping stories with your coworker about your hot dates last weekend and you notice that your coworker has started to blink a lot more than usual, then chances are good that your coworker isn’t telling you a true story. Rapid eye blinking indicates an increase in brain activity, and quite a bit of brain activity is required to construct a lie. Think about it: in order to lie convincingly, you have to ensure that the elements of your story fit together in a coherent way, that your behaviour isn’t giving you away, and that you’ve told everyone the same version of your lie. The self-control alone that’s needed to pull off a lie would be enough to send your brain into overdrive.

17. You catch your conversation partner concealing their hands

You might have noticed someone putting their hands behind their back while talking to you about their latest sales figures. Or you might have seen someone shove their hands in their pockets while congratulating you on your promotion. Some liars fidget when telling a lie, and a likely hot spot for fidgeting is the hand. Liars will sometimes subconsciously conceal their hands to hide fidgety fingers from prying eyes. While hand fidgeting isn’t a foolproof sign of lying, it can suggest that a person is telling a fib, especially if this behaviour is out of character for that person. If you catch someone hiding their hands, then be on the lookout for other signs of lying.

16. You spot a person quietly mauling their lips.

It turns out that Meghan Trainor was on to something with her song, “Lips Are Movin.” Some people become suddenly preoccupied with their lips while lying. They might gnaw at their lips until they draw blood, or lick them so often that they get tongue burn. Like rapid eye blinking, biting or licking of the lips can signal an increase in brain activity, which is necessary to telling a convincing lie. Once more, the key is to determine whether a person is a regular lip muncher, or whether they reserve that behaviour for special occasions requiring a lie. If a person only licks their lips while fawning over your Christmas sweater, for example, then you might want to consider a change of clothes.

15. Your conversation partner unexpectedly flares their nostrils

Have you ever been talking to someone and suddenly noticed their nostrils widen? If so, then you probably checked to see if there were any strange odours in the air, but perhaps you couldn’t manage to get a whiff of anything smelly. There’s another possible reason for your conversation partner’s sudden nostril flaring, one that has nothing to do with funky smells. Unless, of course, you believe that you can smell lies. Nostril flaring is yet another indicator of increased brain activity, which is itself an indicator of lying. Beware of large nostrils, for they may signal the presence of a liar.

14. You watch as your conversation partner’s face changes colour

We’re all familiar with the concept of blushing. We blush when we feel hot, or when we feel nervous or embarrassed about something. Some liars blush while lying, their cheeks turning a pale shade of pink. That’s to be expected since lying can be anxiety-provoking. But did you ever consider that the colour of someone’s nose could indicate that they’re lying? It turns out that lying can be associated with a change in colour in the nose, the nose either turning pale or red. This curious phenomenon has been dubbed the Pinocchio effect. The next time that you suspect someone of lying to you, don’t forget to look to the nose as well as the cheeks, only don’t expect it to grow.

13. You pick up on a person’s contradictory gestures

Our words don’t always match our actions, even when we’re not intending to lie. Occasionally, liars will betray themselves by engaging in behaviour that contradicts the story that they’re telling. For example, a liar might unconsciously shake their head no when answering a question in the affirmative. Or, a liar might speak in a light tone while discussing how sad they feel that their parent died of lung cancer. When words and gestures, or words and tone of voice, don’t match, you can be sure that one of the two is a lie. Spoiler alert: it’s most likely the words.

12. You detect beads of sweat on your conversation partner’s forehead

Lying? No sweat! Or maybe a little bit of sweat. Sweating is a symptom of anxiety, and anxiety often accompanies a lie. Some liars break out in a cold sweat as their lie unfolds; others sweat the lie out without physically perspiring. If your conversation partner isn’t prone to sweating, or if they’re known for sweating when telling a lie, then the beads of sweat on their forehead could be a warning sign to you to go fact checking. Just be sure not to jump to the conclusion that someone’s lying based on their excessive sweating alone. It might be really hot in the room, or they might have recently developed a thyroid problem. Sounds plausible, right?

11. Your conversation partner’s breathing speeds up or slows down

You might have noticed that your brother suddenly started breathing really fast as you ask him questions about his wife’s health. Or you might have heard your husband’s breathing slow down as he reports his whereabouts to you about the previous night. Changes in breathing patterns can be a giveaway that you’re being lied to. Deep breathing, for instance, suggests that the brain has increased its activity. By now, you’re probably familiar with what’s associated with increased brain activity (hint: it rhymes with trying). If mindfulness has taught us one important lesson, it’s to pay attention to our breathing. In this case, you should pay attention to the breathing of others just as mindfully.

10. Your conversation partner’s speech speeds up or slows down

Changes in speech rate are another potential giveaway that you’re talking to a liar. If you notice a person start speaking as if they’ve been hit with the fast forward button, then watch out for a lie. Quickening speech can be a manifestation of an unconscious desire to get the lie out as fast as possible. Like ripping the Band-Aid off, so to speak. Alternatively, a person whose speech becomes more deliberately drawn out might also be lying. Slowing speech can be a sign of laboured processing of a lie. The more complicated the lie, the longer it takes for the brain to piece it together. Hence why a person may talk like a zombie while their brain works to produce a coherent lie.

9. Your conversation partner avoids using personal pronouns

One interesting sign that you’re talking to a liar involves a grammatical lesson on the personal pronoun. As the name suggests, personal pronouns refer to a particular person. In this case, keep in mind the personal pronouns, “me,” “my,” and “I.” Consider the following sentence: “It was possible to find a babysitter for the children even though it was short notice.” Now compare it with this sentence: “I was able to find a babysitter for my children even though it was short notice.” A clue that someone is lying to you is when they stop referring to themself  in conversation. Liars psychologically distance themselves from their lies by removing personal pronouns from their narratives. A lack of personal pronouns is conspicuous when people tell stories about themselves.

8. You’re bombarded with superfluous details when listening to a story

There is such a thing as too much detail, especially when it comes to liars. Liars will sometimes embellish their stories to make them seem more plausible. An adjective here, an adverb there. You should become concerned when someone who isn’t usually very verbal suddenly tells an elaborate story, complete with lengthy sentences and complex imagery. You don’t need to know what someone had for breakfast to understand why they showed up late to work. Keep an ear out for extraneous information when trying to spot a liar, unless you’ve already been bored to death by all of those pesky details.

7. Your conversation partner’s smile doesn’t reach their eyes

We’ve all been in situations where we had to feign happiness in order to spare someone’s feelings. Whether you had to pose for a picture that you weren’t really feeling, or whether you had to pretend to be excited to see your nosy aunt, you most likely plastered on a smile in an attempt to appear cordial. Smiles can be deceiving; they make you look happy, but that happiness might actually be a lie. There’s a subtle difference between an honest and a fake smile. An honest smile engages both the mouth and the eyes, while a fake smile only makes use of the lips. When a person’s smile isn’t reflected in their eyes, it probably isn’t genuine.

6. Your conversation partner has trouble recounting events backwards

I’ll admit that this one sounds strange, but it’s an interrogation tactic used by police officers and FBI agents to determine whether a suspect is telling the truth. False memories are harder to recall in reverse order than are true memories. If you suspect that someone is telling you a fabricated story, then ask them to recount the events of that story from end to beginning. If that trips them up, then you may have caught them in a lie. Then again, people have trouble saying the alphabet backwards, so don’t rely solely on the backwards tactic to detect liars.

5. You detect inconsistencies in a person’s story

We don’t always pay close attention to the stories that people tell us, even though we know that we should. Inattention is how liars get away with their lies most of the time. They count on us not being fully engaged in a conversation to pull the wool over our eyes. Simple active listening skills can go a long way towards ferreting out a liar. If you follow a story carefully, then you might notice that some of the details don’t make sense in the same context. For example, if a person says that they arrived home at 11 p.m., then mentions watching the latest episode of How to Get Away with Murder live, you know that they’ve lied because HTGAWM airs live at 10 p.m. Don’t underestimate the power of active listening.

4. You catch sight of a microexpression that’s at odds with an expressed emotion

We can’t control our microexpressions, so pay close attention to those. Microexpressions are expressions that last less than a second and which reveal a hidden emotion. If, for instance, a person is trying to conceal their fear of roller coasters by smiling excitedly at their friend’s proposal to ride one, then a momentary expression of fear will flash across that person’s face. Blink and you’ll miss it, which is why you have to be paying close attention to spot microexpressions. Fortunately, catching microexpressions can be trained. If you feel that you’re surrounded by liars, then you might want to consider taking a crash course.

3. Your conversation partner holds eye contact with you for an uncomfortable amount of time

People think that liars avoid eye contact, when in fact they maintain eye contact for longer periods of time than non-liars do. Knowing that people assume that they’ll avert their gaze while telling a lie, liars sometimes overcompensate by locking their eyes with you for longer than is necessary to convince you of their honesty. People typically maintain eye contact for three to five second intervals during everyday conversation. If you notice someone holding your gaze for a much longer interval, then your lie detector sensors should go off. The way I see it, they’re either attracted to you or lying to you. I’d go with the latter option.

2. Your conversation partner’s voice gets higher

Changes in pitch can give a lie away faster than a fine-tuned lie detector. Usually, our voice rises in pitch when we lie. Before we know it, we sound like Spongebob Squarepants hopped up on helium. Perhaps our voice rises in pitch when we lie in the hopes that it’ll get so high that no one will be able to hear it. Only dogs will catch the lie at that point. Or maybe it’s a sign of self-control being used up to construct an elaborate lie, leaving us unable to keep our voice at a level pitch. Either way, it’s amusing to imagine a liar talking their way out of a lie in a voice that sounds like Anna Faris in House Bunny.

1. Your conversation partner takes long pauses in between sentences

Liars sometimes hesitate more than they should during a conversation. A pause following a sentence might indicate that a person is thinking about how best to deliver a lie. Pauses are a definite warning sign when they colour the speech of someone who’s normally a fluent speaker. If a person who normally speaks without thinking suddenly has to think before speaking, then chances are high that that person is busy constructing a lie. Lies certainly don’t come as easily to us as the truth, which is where the pauses come in. They buy us some time while we think up the next portion of our latest lie.

Sources: psychology.com, dailymail.co.uk, webmd.com, independent.co.uk