Is it worth spending some extra time in bed?
-Lack of sleep:
increases the likelihood of increased food consumption (1) (but also total energy expenditure) (2)
can lead to decreased fat loss (3,4) and increased loss of fat free mass
(muscle) on a weight loss diet (4)
may increase the risk for depression (5)
is associated with increased risk of diabetes and obesity (8)
increases stress levels (5)
-Increased sleep duration/quality:
can potentially increase sports performance (9)
improves physical and mental wellbeing (9)
improves attractiveness (10)
In today’s society there is an increasing will and push towards being the perfect you; whether you’re striving for that promotion at work, the highest grade in school, that perfect body, or to be the perfect parent for your kids. There is always something to improve and work on.
It’s an attractive and simple solution to skimp on sleep in order to have time to accomplish more in a day. But by doing so you might just be shooting yourself in the foot. Let’s say you sacrifice a few hours in bed for working that extra hour or watching one last episode of your favorite TV series. It will affect more than just your alertness the next day. Sleep deprivation can actually have an impact on the effectiveness of your diet and cause you to overeat (1). One study investigated if a calorie-restricted diet (90% of resting metabolic rate) would be affected by a two-week sleep restriction (5.5 hours in bed) compared to less sleep restriction (8.5 hours in bed). The results showed an increased loss of fat-free mass (usually correlated with muscle mass) and a decreased fat loss (4). This is the complete opposite of what most people try to achieve with a diet. I mean, who wants to get weaker and lose less fat?
As mentioned above, lack of sleep can also cause people to overeat (1) which further complicates reaching your dieting goals.
As if this wasn’t enough, sleep loss can also shorten attention span and increase the risk of forgetting to do planned tasks (6). If you’re well-rested, your learning improves, and after acquiring the new information, your sleep plays an important role in consolidating and integrating it (7). With this in mind is seems a bit counterproductive to cram in an additional study session at the expense of extra sleep, that is if you even remember to do that extra planned study session after a bad night’s sleep 😉
Poor sleep has also been linked to depression, other mood disorders and stress (5) and even metabolic dysregulation with increased risk of type 2 diabetes (8).
What if you are a competitive athlete or just want to perform well in the gym/your preferred sport? Well, unfortunately bad news again. Since the abovementioned cognitive effects of sleep loss also impact performance, learning and recovery, it comes as no surprise that sports performance would be negatively affected. Furthermore, accuracy, pain tolerance, recovery, and decision-making ability seem to decrease (11). However, this is not as black or white as one would first think. Anaerobic (not relying on oxygen, often short duration, high effort) performance seems to be relatively unaffected by sleep loss compared to aerobic more endurance type exercise (in which performance seems to decrease) (12). But even if there might be some conflicting results with regard to performance after sleep loss, the safest bet would still be not to sacrifice those precious dates with the pillow.
So, if I haven’t convinced you of the importance of sleep already I am going to use an ace in the hole. A study published in 2010 showed that participants who had been sleep restricted (5 hours of sleep followed by 31 hours of wakefulness) were rated as less attractive and less healthy compared to a group with no sleep restriction (> 8 h of sleep) (10).
This is only a brief summary of some of the effects sleep deprivation can have on your body. The main message here is, it’s not always beneficial to sacrifice sleep for that extra study session, or to wake up that hour earlier to do an extra cardio session. You may have just taken one step forward, and two steps back by doing so.
Sometime soon I will give you some practical tips on how to improve sleep quality and quantity so you can reap the benefits of a good night’s sleep.
RELATED: Want to Lose Weight? Start with This
Referenced books and articles
Be a healthier you!Sign up for Lifesum