Nutrition Notes

Less Sleep Associated with Increased Impulsivity

There’s no doubt that getting too little sleep (or less than an adequate amount) impacts our moods, cognitive abilities and how we feel the next day. Not to mention that when we are sleep deprived, we tend to make more mistakes and notice overall impairments in our ability to concentrate. This can greatly impact our work and daily lives.

Previous research demonstrates that insufficient sleep “can impair your ability to drive the same way as drinking too much alcohol.” Furthermore, poor sleep is linked to a suppressed immune system that can increase susceptibility to infection, which is something we definitely want to avoid, particularly right now considering the current, global pandemic. 

The National Sleep Foundation recommends that young adults should normally sleep 7 to 9 hours per night and older adults 7 to 8 hours. However, nearly 30% of all adults in the U.S. reported they sleep less than 6 hours each night, according to the 2012 U.S. National Health Survey

A recent study published in the journal Sleep indicates that even mild-to-moderate, partial sleep deprivation (i.e., 1.5 to 2 hours less sleep than the average required) in a naturalistic setting can cause increased impulsive behavior and reduced positive emotions (i.e., emotional blunting). In comparing this with normal sleep needs, even partial sleep deprivation impairs our normal activities. 

Researchers investigated the effects that 1.5 to 2 hours less sleep per night for three consecutive nights had on participants’ cognitive and affective processes. They analyzed participants’ response accuracy and speed while engaging in a continuous performance test, along with participant-reported subjective measurements (e.g., how exhausted they felt and how well they believed they had performed). Participants showed poorer cognitive control functioning, as emulated by increased impulsivity, which was demonstrated by faster reaction times, but with more errors. Participants also experienced more exertion, poorer subjective performance and decreased positive effects, confirming the observations of previous studies

There were no marked differences in negative emotions, but considerable differences were found in the participants’ positive emotions, with participants stating that “positive feelings scored worse after just one night of reduced sleep and dropped even more after three nights. … We already know that fewer positive emotions have a major impact on mental health.” One of the lead investigators of this study explains that less sleep didn’t cause feelings of depression, but study participants “experienced a flattening of emotions. … [and] they felt less joy, enthusiasm, attention and fulfillment” with fewer hours sleep than normal.

Considering this occurs after only three consecutive nights of insufficient sleep hours each night, then these results suggest that chronic sleep deprivation over time may have major deleterious effects on mental health. Poor sleep is a factor in nearly all mental health diagnoses.

Researchers also stated that “the sleep loss many individuals experience during a normal week significantly affects morning cognitive and emotional functioning, which may increase the risk of mistakes and accidents in everyday life.” The authors of the study conclude that sleep deprivation may also limit one’s “capacity to manage negative life events and stress.” 

For these reasons, ensuring adequate sleep is essential for many optimal functions of the body, such as the metabolic processes, proper restoration and healing, and robust immune response maintenance. However, it is critical to ensure optimal brain and nervous system function to support cognition and learning, and an overall positive mental outlook.

In this recent article, we discuss various ways to manage healthy sleep patterns. These include sleep hygiene techniques, specific nutritional supplements and botanicals, and adopting a healthier dietary intake with healthy lifestyle patterns to support adequate and restorative sleep.