From how long a person should sleep to the effect of alcohol on falling asleep faster, there are many myths about sleep that are not true.
There are misleading claims about sleep that can lead to bad habits and poor sleep hygiene, leading to reduced sleep quality and negative health outcomes. In this article, citing Live Science, we mention eight examples of common myths related to sleep.
Eating cheese causes nightmares
While cheese is often said to cause bad dreams, according to a 2015 review published in the journal Frontiers in Psychology, there is no evidence that cheese causes nightmares.
The mentioned study showed that unpleasant or vivid dreams are more related to emotional and uncontrolled eating than they are related to the type of food eaten. However, according to a study published in 2019 in the journal Molecular Nutrition and Food Research, eating late at night may lead to sleep disturbances. The reason is that when the body tries hard to digest food, the body's circadian rhythm (the internal clock that regulates the body's sleep and wake cycle) is disrupted and the natural sleep pattern is disturbed.
According to the US Sleep Foundation, irregular or insufficient sleep can cause vivid dreams and nightmares; Therefore, it is better to avoid eating late (cheese or any other food) in order to have a restful sleep without dreams.
Alcohol helps you sleep better
Guy Meadows, sleep researcher and co-founder of the online platform The Sleep School, told LiveScience that while alcohol has a sedative effect and helps you fall asleep faster, it has a negative effect on the quality and duration of sleep. "Alcohol directly reduces REM (rapid eye movement sleep), which is critical for memory and emotional processing," Meadows explained. REM sleep usually begins about 90 minutes after falling asleep. "If you have a lack of REM sleep, you may have trouble concentrating, learning, and long-term memory."
A review study published in 2018 in the journal Sleep Medicine found that alcohol increases the risk of snoring and sleep apnea (a condition in which a person experiences pauses in breathing or shallow breathing during sleep), leading to more disrupted sleep.
Everyone needs eight hours of sleep a night
According to Meadows, there is no exact answer for the amount of sleep each person needs; But there are general recommendations for each age group. For example, according to the recommendations of the US National Sleep Foundation, every normal adult needs 7 to 9 hours of sleep; But some people may need 6 hours and some 10 hours of sleep. The amount of sleep we need is determined by our stage of life and health and the amount of energy we consume during the day. "Each of us needs the right amount of sleep to stay healthy, and it's unique to each person," Meadows said.
Five hours of sleep is enough
While some people seem to be able to cope with less sleep, most people need more sleep. According to a review study published in 2017 in the journal Sleep Medicine, shorter sleep duration is associated with obesity, diabetes, heart disease and high blood pressure. Although scientists have discovered two genetic mutations that may give people the ability to sleep less naturally and not suffer the negative effects of sleep deprivation, these mutations are rare and most people need more than 5 hours of sleep.
"Since our biological need for sleep is rooted in our genes, we must note that a person cannot change and control the amount of sleep they need," says Meadows. It is important to recognize the amount of sleep a person needs; Because fulfilling it is vital to maintain health.
Older people need less sleep
Another common misconception is that older people need less sleep. According to a study published in the journal Sleep Health in 2019, this group of people often cannot get enough sleep. "By the time we reach our sixth decade, we lose up to 70 percent of the deep sleep we had in our third decade," says Meadows. Needless to say, the suggestion that older people need less sleep is a myth. "Decreasing deep sleep and increasing sleep-disrupting medical problems and their accompanying medications make it more difficult for them to achieve adequate quality sleep."
The most common problems that disturb the sleep of adults are the increased need to go to the bathroom due to a weak bladder and physical discomforts and pains such as arthritis. Sleep-related disorders such as sleep apnea and restless leg syndrome are also more common in the elderly.
For comfortable sleep, it is better to have a warm bedroom
According to a study published in Sleep Health magazine in 2019, in order to have a comfortable sleep, a cooler sleeping environment with a temperature between 18 and 21 degrees Celsius is recommended. Higher temperatures can create a hot and stuffy atmosphere and lead to poor sleep. "Turn off the central heating and replace your summer-style comforter with a winter comforter, or use a combination of sheets, duvets and blankets to help you set the right temperature for your night's sleep," Meadows said.
Snoring is not harmful
Occasional mild snoring may be harmless; But persistent loud snoring is a sign of obstructive sleep apnea. Obstructive sleep apnea is a condition in which people experience pauses in breathing or shallow breathing during sleep. According to the American Sleep Foundation, about 9% of American adults suffer from sleep apnea.
According to the Mayo Clinic, in addition to causing discomfort to the person sleeping next to the person with the condition, obstructive sleep apnea can lead to serious complications such as cardiovascular disease, heart failure, and stroke. If you snore regularly, see a doctor.
Evening exercise disrupts sleep
People who enjoy jogging or going to the gym after work don't have to worry about disturbing their sleep. A 2016 study published in the journal Sleep Medicine examined the exercise habits and self-reported sleep quality of 1,000 American adults. The aforementioned study concluded that people who exercised in the evening less than four hours before going to bed had no problems falling asleep or staying asleep throughout the night. In fact, these people reported sleeping better on the nights they had previously exercised than on the nights they hadn't.
A 2019 review published in the journal Sports Medicine reviewed more than 20 studies on exercise and sleep and found that people who exercised in the evening had deeper sleep and reduced first-stage sleep. The first stage of sleep is the lightest stage of sleep. However, researchers found that an hour or less of vigorous exercise before bed negatively affected sleep quality.