Sleep Deprivation: Rain Or Shine?

The sound of rain can be soothing, and many people find themselves nodding off during a downpour. There are several reasons why rain makes people sleepy. One is the lack of sunlight. When exposed to sunlight, the human body releases less melatonin and more serotonin, making people feel more alert and cheerful. The lack of light on a rainy day can have the opposite effect, making people feel drowsy. The sound of rain also plays a part. Rain is pink noise, which includes all the frequencies humans are able to hear, and a 2012 study found that pink noise reduces brain waves, making it a potential sleep aid.

Rain is a form of white or pink noise

Pink noise, on the other hand, is a mix of high and low frequencies, with lower frequencies louder and more powerful than higher ones. It is often considered more soothing and easier to listen to than white noise. The higher frequencies in pink noise are less intense, replicating the way humans hear sound. This is why pink noise is perceived as a more pleasant sound than white noise.

Rain can be either white noise (heavy rain) or pink noise (steady rain). While white noise may help you fall asleep faster, pink noise is a more powerful and louder sound at lower frequencies, which makes it a more effective sleep aid.

Rainfall sounds are a soothing form of pink noise and can be found in nature. The sound of rain can induce a meditative feeling and trigger alpha waves in the brain, relaxing our over-stimulated brains and helping us sleep more quickly.

If you're looking to improve your sleep quality, it is recommended to focus on maintaining a consistent sleep schedule, avoiding naps and caffeine, and following a nighttime routine.

Lack of sunlight

Additionally, the dim light on rainy days stimulates the pineal gland to produce melatonin, a hormone that regulates our circadian rhythms and signals to our bodies that it is time for sleep. As melatonin levels rise, we naturally feel more tired and are inclined to sleep. This is why we tend to sleep less during the summer months when sunlight is more abundant, as it prevents the release of melatonin.

The gloomy atmosphere associated with rainy weather can also negatively impact our emotional state. A 2011 study found that 9% of people felt angrier on rainy days compared to sunny days, further highlighting the link between lack of sunlight and negative emotions.

To counteract the effects of reduced sunlight during rainy weather, it is recommended to maximise exposure to natural light. Spending time outdoors, even on overcast days, can provide some beneficial UV light. Alternatively, bright indoor lighting can serve as a secondary option. Staying active, both physically and mentally, is another effective strategy to boost serotonin levels and combat the sleepiness induced by a lack of sunlight.

Rain is a non-threatening sound

The sound of rain is also meditative. The repetitive pitter-patter can induce a meditative feeling, relaxing our over-stimulated brains and helping us sleep more quickly. It triggers alpha waves in the brain, which has a calming effect on the body.

Rain is also a form of white noise (heavy rain) or pink noise (steady rain). These types of noise mask out other sounds from our normal hearing range and can be used to drown out other noises, especially when sleeping. Research has shown that this type of noise helps us learn how to sleep better because it helps to synchronize our brain waves. It covers the full frequency range and can cover up most sounds.

The sound of rain is a popular ASMR sleep sound. Many people play recordings of rainfall to help them fall asleep.

Increased humidity

The wetness or humidity of a rainy day is often the last factor contributing to the cycle of sleepiness. The water saturates the air with vapour, creating an innate "heavy" feeling in the world around us. Our bodies then have to work harder to maintain homeostasis, which can be tiring.

On hot, humid summer days, you might experience that sticky, hot feeling—like there's not enough air around you. This is common when it rains, too, as the humidity comes with added pressure. The higher humidity and heat mean our bodies work harder to stay cool, sending blood to the surface of the skin to cool down. This makes us feel fatigued at best, meaning we're more likely to feel tired and want to head to bed early.

If you're feeling tired due to increased humidity, try to stay active, either physically or mentally. Getting some light, especially natural light, will also help to lower your melatonin levels.

Rain masks distracting noises

The sound of rain is a natural sleep aid, and one of the reasons for this is that it masks distracting noises.

Rain is a form of white noise or pink noise, depending on its intensity. White noise is produced by heavy rain, while steady rain creates pink noise. Both types of noise mask other sounds from our normal hearing range, drowning out noises that might otherwise disturb our sleep.

Dr Sue Peacock, a leading health psychologist and sleep specialist, explains that rain "covers the full frequency range and can cover up most sounds". She adds that "the sound of rainfall can mask out [distracting] sounds" such as "car doors slamming, dogs barking, and people talking noisily in the street".

Research has shown that white noise helps adults fall asleep faster, with some people falling asleep up to 38% faster when listening to white noise.

So, if you're struggling to sleep due to distracting noises, the sound of rain might be just what you need to drown out those unwanted sounds and help you drift off into a peaceful slumber.

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