From the dangers of a late-night cheese binge to that recurring nightmare you have about taking the SATs in your underwear, we’re getting to the bottom of these eight misconceptions about dreams, adapted from an episode of Misconceptions on YouTube.

1. Misconception: Eating cheese before bed can give you nightmares.

At one point in Charles Dickens's A Christmas Carol, Ebenezer Scrooge dismisses a ghostly encounter as being just as likely from the crumb of cheese he had before bed. It sounds a bit odd, but cheese has historically gotten a bad rap for its ability to conjure nightmares. It's unlikely that a little cheddar is the root of your nighttime terrors, though.

In 2005, the British Cheese Board funded a study to debunk the myths about cheese causing nightmares. As part of the experiment, 200 participants snacked on 20 grams of cheese a half-hour before bedtime. Sixty-seven percent of cheese eaters reported remembering their dreams, but none of them recorded nightmares. The dreams they did have, however, were pretty funky. One participant detailed dreaming about a vegetarian crocodile who was distressed about not being able to eat children, while another dreamed of soldiers who fought with kittens instead of guns.

The research did also imply that different cheeses had different effects, with Stilton cheese providing the weirdest dreams. It’s worth noting that there are quite a few holes in this study—it’s unpublished, there was no control group, and it was funded by the British Cheese Board, likely as a PR move. But still, it’s unlikely that scary “cheese dreams” are a real phenomenon to worry about.

2. Misconception: We only dream during REM sleep.

There’s a lot we don’t know about dreams, but for a long time, we were certain they only occurred during REM sleep. Now, it has been proven that we actually dream throughout the night during different stages of sleep. We’re just more likely to remember the dreams we have during REM sleep, which was named for the rapid eye movement that happens during that part of our sleep cycle. These REM sleep dreams tend to be more vivid, exciting, and just plain weird. Non-REM sleep dreams, on the other hand, are simpler and less emotional.

3. Misconception: Dreams are entirely meaningless.

While it may be difficult to draw conclusions from any one particular dream, research suggests that dreams are more than just a random montage of scenes that flit through our brains at night. Recurring patterns in dreams often accurately reflect concerns people have about their daily lives. And those dreams you had about being unprepared for a test or showing up to class in your underwear aren’t limited to your high school days. A person is likely to have those dreams long after they’ve graduated, as they often crop up during times of stress. So, if you’re feeling extra anxious in the days leading up to a job interview, don’t be surprised if your subconscious revives that old math test nightmare.

4. Misconception: Remembering your dreams is an indicator of good sleep.

Some people say that remembering your dreams in the morning is an indication of a good night's sleep, but that's not true. In fact, people with poor sleep are more likely to remember their dreams. According to a 2014 report in Cerebral Cortex, study participants who remembered their dreams had twice as much "wakefulness," which could be taken to mean they woke up more often. People who remember their dreams also have higher activity in the temporoparietal junction, a part of the brain that processes information and emotions. They also reacted more strongly to sounds, which could help explain their interrupted sleep patterns. Basically, people who are sleep-deprived tend to have greater sleep intensity during the precious few hours they manage to sleep, which leads to more vivid dreams.

5. Misconception: Not everyone dreams.

A 2015 French study published in the Journal of Sleep Research sought to find whether or not everyone dreams. The researchers studied individuals with REM sleep behavior disorder, which causes people to act out their dreams while they’re sleeping. Fewer than 4 percent of the study’s participants claimed they never dreamed. But the researcher’s analysis says otherwise. They observed the participants while they slept, and found that even those who denied dreaming still moved in a way that suggested they were, in fact, dreaming. It’s more likely people just don’t remember their dreams. Though adults average four to six dreams per night, most people forget between 95 to 99 percent of them.

6. Misconception: Dreams can kill you.

No, your dreams won’t kill you—though, for a time, people believed they could. In 1981, it was reported that Southeast Asian refugees who fled from violent regimes died from heart attacks in their sleep. The suspected heart-weakening culprit? PTSD-induced nightmares. But as it turns out, these mysterious nighttime deaths were already a problem across Asia and other parts of the world. The nighttime terrors weren’t triggering the lethal heart attacks, however.

More recent research has linked the medical emergencies to a genetic disorder called Brugada syndrome. In this case, it’s REM sleep, not dreams, that are the danger. Your heart rate becomes less stable during this part of the sleep cycle, putting those with heart disease at greater risk.

7. Misconception: Dying in a dream means the real thing isn't far behind.

According to one popular myth, dying in a dream means you’ll soon die in real life. Fortunately, there's no scientific proof that dreaming of death will spell your actual doom. Instead, death dreams have been interpreted to be about big life changes or to symbolize a major ending, like leaving a job or ending a relationship. So, even if you do find yourself confronting your own mortality in a dream, you’ll still most likely live to see another day.

8. Misconception: Abraham Lincoln dreamed he died right before his assassination.

One of the most famous death dream myths is that President Abraham Lincoln had a dream that predicted his own demise. According to the president’s friend and bodyguard, Ward Hill Lamon, shortly before he was assassinated, Lincoln told a group of people about a dream he had. In the dream, he asked a group of mourning soldiers who had died. They responded, “The president. He was killed by an assassin.” But modern historians doubt how honest this premonitional tale may have been, thanks to inconsistencies surrounding Lamon’s story.

In some accounts, Lincoln had this dream 10 days before John Wilkes Booth pulled the trigger; in others, Lincoln foresaw his death just “a few days” before his fateful trip to the theater. There’s also the fact that neither Lamon nor Lincoln’s wife mentioned the dream in the immediate aftermath of the assassination—Lamon didn’t publish the tale until 20 years later.