Lack of sleep, or sleep deprivation, occurs when a person consistently does not get enough quality or quantity of sleep. If this persists long-term, it can contribute to poor immune system function, irritability, difficulty concentrating, and delayed reaction times. The National Health Service suggests establishing a routine by waking up and going to sleep at similar times each day, reducing screen time before bed, and giving yourself time to relax in the evening where possible.
The amount of sleep needed varies depending on age and can also be influenced by genetics and lifestyle. Some people may feel energised after six hours of sleep, while others may not feel fully rested even after eight.
There are also people who experience insomnia, meaning persistent difficulty falling or staying asleep. This can be linked to factors such as stress, anxiety, alcohol or caffeine intake, health conditions, or jet lag. The distinction between sleep deprivation and insomnia is that sleep deprivation is often related to lifestyle or habits limiting sleep opportunity, whereas insomnia involves difficulty sleeping even when someone wants to rest.
If you've been training intensely, studying for long periods, or simply feeling fatigued, taking time to rest properly can make a noticeable difference.
As you might know, there are different stages of sleep: NREM stages 1, 2, and 3, as well as REM sleep, which stands for Rapid Eye Movement. REM sleep is associated with vivid dreaming and increased brain activity, while deep sleep (NREM stage 3) plays an important role in physical recovery and restoration. These stages help support learning, memory, and overall recovery. So, if you've been training intensely, studying for long periods, or simply feeling fatigued, taking time to rest properly can make a noticeable difference.
Diving into the brain side of things, our brain is essentially the command centre of the body. It regulates everything from movement and emotion to memory and decision-making. However, in my opinion, we often do not appreciate how important sleep is for maintaining these functions.
“How come?” I hear you ask. Wendy Suzuki, professor of neural science and psychology at New York University, highlights two key reasons, among many others.
“When having regular healthy sleep, activity in the hippocampus, the area deep inside your brain, helps strengthen your ability to remember information from the previous day.”
When you don’t get enough sleep or sufficient time for this process, information may not consolidate as effectively, making it more difficult to retain and recall later.
This process is called consolidation. According to Yale School of Medicine, it is especially linked to slow-wave sleep, during which encoded information is organised and reinforced through chemical connections, supporting long-term memory storage. When you don’t get enough sleep or sufficient time for this process, information may not consolidate as effectively, making it more difficult to retain and recall later.
Dr. Suzuki further emphasises the importance of the brain processing metabolites during sleep. Metabolites, the small molecules crucial for neural function and energy production, are cleared from the brain through the circulation of cerebrospinal fluid. Insufficient sleep may interfere with this process, which researchers believe could contribute to the build-up of waste products and certain proteins in the brain over time.
Research has consistently shown that improving sleep habits can support overall health, mental well-being, concentration, and daily functioning. The underlying message of this article is that before immediately turning to medication, it may be worth considering whether inadequate sleep could be affecting your daily life in ways you have not recognised.