It’s important to get enough sleep– at least 7 hours a night for most people, and up to 9 hours for those who are more physically active.  But what about quality of sleep?

Sleep quality– defined as the percentage of time spent in REM and deep sleep– can be low even when total sleep time is sufficient.  This can happen for a variety of reasons– caffeine, sleeping conditions, anxiety, or even your diet.  

Here are six different approaches to improving not only your quantity, but your quality of sleep.

Go Dark At Night

Exposure to light while sleeping, even at very low levels, increases your risk of sleep disorders and depression.  In fact, it takes a surprisingly small amount of light to make a difference.   

One Japanese study found that nighttime light exposure as low as 5 lux– about the brightness of a candle from 2 feet away– increased the risk of depression by 89%, even after adjusting for age, sex, body mass index, and socioeconomic status.

Blocking blue light from reaching your eyes in the last two hours before bedtime improves sleep quality and speeds time to sleep in adults suffering from insomnia.  This can be accomplished by wearing orange-tinted goggles. 

The easiest solution, however, is to install blackout curtains in your bedroom in order to keep it dark at night.  Similarly, you can use the evening settings on your devices to make them darken and redden at night, reducing the amount of blue light they emit.   

Exercise Every Day

It should come as no surprise that regular exercise increase both the quantity and quality of sleep.  But exactly how much do you need?

A 2017 systematic review of studies on exercise and sleep found that sleep benefits consistently appeared at 30 minutes of exercise, three days a week.  However, more regular exercise appears to be better; you can improve your sleep more if you exercise every day.

As for what kind of exercise is best, so far there’s no indication that it matters very much.  For sleep purposes at least, you can exercise however you want– just shoot for a half hour a day.

Take CBD In The Evenings

Cannabidiol, or CBD, is currently gaining something of a reputation as a cure-all.  Among other things, people take it to help them sleep.  As it turns out, that’s a good idea, though maybe not for everyone.

The evidence for CBD as a sleep aid has actually been pretty mixed, with some studies finding that low doses actually promote wakefulness, and others finding sleep induction only in combination with THC.  

However, CBD is well-established as an anxiolytic- an anti-anxiety compound– and CBD studies on patients who suffer from anxiety consistently find improvements in sleep as well as anxiety.  Accordingly, people with anxiety-related sleep difficulties should consider using CBD as a sleep aid.

Be aware, however, that CBD has a half-life of 18 to 32 hours.  If you take it in the evening, it will still be in your bloodstream in significant quantities throughout the next day.  While CBD studies have often tested doses in the range of several hundred milligrams a day, most people will be better off keeping their CBD dosage in the low tens of milligrams a day.

Drink Less Caffeine, And Drink It Earlier

You know that caffeine has deleterious effects on sleep, but you probably don’t realize just how bad it is, or how little caffeine it really takes.  

Not only does caffeine makes it harder to get to sleep, but it also reduces your sleep quality even after you do fall asleep.  

In fact, drinking as little as 150 mg of caffeine first thing in the morning– the equivalent of two cups of coffee or three cans of Coke– is enough to measurably and significantly reduce the time spent in deep, slow-wave sleep that night, 16 hours later.

Notably, people seem to become more sensitive to caffeine the older they get.  At some point you may not be able to get away with as much caffeine consumption, as late in the day, as you used to. 

Practice Mindfulness Meditation 

Meditation is a great way to reduce anxiety and improve both sleep onset (how fast you get to sleep) and sleep quality.  It works best, naturally, for improving sleep in people who have anxiety or racing thoughts that makes it harder to get to sleep, or who suffer from comorbid depressive symptoms.

One study found that mindfulness meditation reduced insomnia symptoms by about 25%, compared to 10% for a sleep hygiene education program.  Depression and fatigue symptoms were also reduced, though curiously in this case, not anxiety.  

For those who have trouble meditating, guided meditations for sleep can be found on YouTube.  

Eat Most Of Your Carbs In The Evening

Yes, nutrient intake, and nutrient timing, affects your energy level and mental state.  A protein-rich breakfast will give you more energy for the day.  Conversely, a high-carb dinner, especially later in the evening, may help you sleep at night.  

Eating a carbohydrate-rich meal causes the brain to synthesize more tryptophan and serotonin.  Tryptophan you may recognize as an amino acid that helps people relax– famously the reason why turkey is lauded as a good food to eat in the evening.

You probably also recognize serotonin as the neurotransmitter associated with relaxed happiness– as oppose to the more high-energy happiness and motivation of dopamine.  

What you may not know is that serotonin is also the precursor to melatonin, the main neurotransmitter responsible for sleep onset.  Eating more carbohydrates in the evening will provide your brain with the resources it needs to produce more melatonin, helping you get to sleep fast and sleep more deeply, earlier in the night.