We’ve all heard it before: getting enough sleep is important. Sometimes though, it’s hard to resist pulling an all-nighter when we’ve got a big exam to study for. What most people don’t realize however, is that they may actually be doing themselves a disservice because sleep is required for memory consolidation. New research shows that declarative memories (like a series of facts) benefit from getting some shut-eye. But the benefits of sleep go far beyond memory consolidation; it keeps our immune systems active and healthy, and can also balance our appetites by helping to regulate levels of the hormones ghrelin and leptin, which play a role in our feelings of hunger and fullness. So when we’re sleep deprived, we may feel the need to eat more, which can lead to weight gain.
But what exactly is it about sleep that is so critical for our bodies to work properly? According to the National Sleep Foundation, each stage of sleep has a different role in body function. Sleep is characterized by two main stages, NREM (75% of the night) and REM (25%).
During NREM:
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Blood supply to muscles increases
- Tissue growth and repair occurs
- Energy is restored
- Hormones are released, such as: Growth hormone, essential for growth and development, including muscle development
During REM:
- Brain is active and dreams occur
- Provides energy to brain and body
- Supports daytime performance
So how much sleep do we really need? A good rule of thumb is between 7 and 9 hours, but certain individuals may benefit from more or less than this.