By Dr. Mercola
Nearly 41 million US adults are sleeping just six hours or
less each night, putting them at risk of adverse health effects
(such as heart disease and obesity) and potentially fatal drowsy
driving linked to lack of sleep.1
While stress is one of the most-often cited reasons why
people can’t sleep, there’s another factor that could be keeping
you up at night: your diet. Certain foods can significantly
interfere with your sleep, including the five worst of the worst
below.
What Are the Five Worst Foods for Sleep?
1. Alcohol
A drink or two before bed can make you drowsy, leading
many to believe it’s actually beneficial for sleep. But
while it may make you nod off quicker, research shows that
drinking alcohol makes you more likely to wake during the
night, leaving you feeling less rested in the morning.
The latest study found that alcohol increases slow-wave
“deep” sleep during the first half of the night, but then
increases sleep disruptions in the second half of the night.2
Since alcohol is a potent muscle relaxant, it can also
increase your risk of snoring. Snorers -- and their bed
partners -- often experience restless sleep leading to
sleepiness and difficulty concentrating during the day.
2. Coffee
Coffee, of course, is one of the most common sources of
caffeine. This stimulant has a half-life of five hours,
which means 25% of it will still be in your system even 10
hours later, and 12.5% 20 hours later (see the problem?).
Plus, in some people caffeine is not metabolized
efficiently, leaving you feeling its effects even longer
after consumption. So, an afternoon cup of coffee or tea
will keep some people from falling asleep at night. Be aware
that some medications contain caffeine as well (for example,
diet pills).
3. Dark Chocolate
Dark chocolate, though the healthiest form of chocolate
from an antioxidant perspective, can contain relatively high
levels of caffeine that can keep you up at night if you’re
sensitive. It also contains theobromine, a compound that has
caffeine-like effects.
4. Spicy Foods
Spicy foods before bedtime can give you indigestion that
makes it nearly impossible to get a good night’s sleep. But
even if you can eat spicy foods without discomfort, they are
still linked with more time spent awake during the night and
taking longer to fall asleep.3
It’s speculated that this may be due to capsaicin, an active
ingredient in chili peppers, affecting sleep via changes in
body temperature.
5. Unhealthy Fatty Foods
When you don’t get enough sleep, you’re more likely to
crave high-fat, high-sugar foods the next day. But eating a
high-fat diet also has impacts on your sleep, including
leading to more fragmented sleep. In fact, an animal study
revealed that eating fatty foods may lead to disrupted sleep
and excessive daytime sleepiness.4
The link may be due to the brain chemical hypocretin, a
neurotransmitter that helps keep you awake and also plays a
role in managing appetite. Keep in mind that while you
should limit your intake of unhealthy fats like those from
fried foods,
healthy fats (including saturated fats) play an
important role in your diet and shouldn’t be eliminated.
Recent Study Gives Clues on How Diet Impacts Sleep
The link between what you eat and how well you sleep, and
vice versa, is only beginning to be explored, however, a recent
study evaluating the diets and sleep patterns of more than 4,500
people did find distinct dietary patterns among short and long
sleepers.5
While the study was only able to generate hypotheses about
dietary nutrients that may be associated with short and long
sleep durations, it did yield some interesting data.
- Very short sleepers (less than 5 hours a night):
Had the least food variety, drank less water and consumed
fewer total carbohydrates and lycopene (an antioxidant found
in fruits and vegetables).
- Short sleepers (5-6 hours): Consumed
the most calories but ate less vitamin C and selenium, and
drank less water. Short sleepers tended to eat more lutein
and zeaxanthin than other groups.
- Normal sleepers (7-8 hours): Had the
most food variety in their diet, which is generally
associated with a healthier way of eating.
- Long sleepers (9 or more hours):
Consumed the least calories as well as less theobromine
(found in chocolate and tea), choline and total carbs. Long
sleepers tended to drink more alcohol.
As for what the data means, researchers aren’t yet sure, but
it could be that eating a varied diet is one key to normal,
healthful sleep. If you need some help in this area, check out
my
nutrition plan for a step-by-step guide to optimizing your
eating habits.
Sleep Tip: Stop Eating at Least Three Hours Before You Go to Bed
It is ideal to avoid eating any food three hours before bed,
as this will optimize your blood sugar, insulin and leptin
levels and contribute to overall good health and restful sleep.
Specifically, avoiding food for at least three hours before bed
will lower your blood sugar during sleep and help minimize
damage from too much sugar floating around. Additionally, it
will jumpstart the glycogen depletion process so you can shift
to fat-burning mode.
A recent study6
is a powerful confirmation of this recommendation, as it found
that the mere act of altering your typical eating habits — such
as getting up in the middle of the night for a snack — causes a
certain protein to desynchronize your internal food clock, which
can throw you off kilter and set a vicious cycle in motion.
Eating too close to bedtime, or very late at night when you'd
normally be sleeping, may throw off your body's internal clock
and lead to weight gain.
Routinely eating at the wrong time may not only
disrupt your biological clock and interfere with your sleep, but
it may also devastate vital body functions and contribute to
disease.
That said, while you’ve likely heard the advice that
breakfast is the most important meal of the day, some
experts believe that skipping breakfast and
eating your main meal at night may actually be more in-tune
with your innate biological clock. I've revised my own eating
schedule to eliminate breakfast and
restrict the time I eat to a period of about six to seven
hours each day, which is typically from noon to 6 or 7 pm.
Diet Is Only One Factor in Getting a Good Night’s Sleep
There are many variables that impact how well you sleep. I
suggest you read through my full set of
33 healthy sleep guidelines for all of the details, but to
start, making some adjustments to your sleeping area can go a
long way to ensure uninterrupted, restful sleep.
- Cover your windows with blackout shades or
drapes to ensure complete darkness. Even the
tiniest bit of light in the room can disrupt your pineal
gland's production of melatonin and the melatonin precursor
serotonin, thereby disrupting your sleep cycle.
So close your bedroom door, get rid of night-lights, and
refrain from turning on any light during the night, even
when getting up to go to the bathroom. If you have to use a
light, install so-called "low blue" light bulbs in your
bedroom and bathroom. These emit an amber light that will
not suppress melatonin production.
- Keep the temperature in your bedroom at or below
70 degrees F (21 degrees Celsius). Many people keep
their homes and particularly their upstairs bedrooms too
warm. Studies show that the optimal room temperature for
sleep is quite cool, between 60 to 68 degrees F (15.5 to 20
C). Keeping your room cooler or hotter can lead to restless
sleep.
- Check your bedroom for electro-magnetic fields
(EMFs). These can also disrupt your pineal gland's
production of melatonin and serotonin, and may have other
negative effects as well. To do this, you need a gauss
meter. You can find various models online, starting around
$50 to $200. Some experts even recommend pulling your
circuit breaker before bed to kill all power in your house.
- Move alarm clocks and other electrical devices
away from your head. If these devices must be used,
keep them as far away from your bed as possible, preferably
at least three feet.
- Reduce use of light-emitting technology, such as
your TV, iPad, and computer, before
going to bed. These emit the type of light that
will suppress melatonin production, which in turn will
hamper your ability to fall asleep, as well as increase your
cancer risk (melatonin helps to suppress harmful free
radicals in your body and slows the production of estrogen,
which can contribute to cancer). Ideally, you'll want to
turn all such light-emitting gadgets off at least
one hour prior to bedtime.
© Copyright 1997-2013 Dr. Joseph Mercola. All Rights Reserved.