Most people focus on improving diet and exercise when shifting to a healthier lifestyle. There’s no doubt those are both key components. What’s even more critical, though, is a good night’s sleep.
How you sleep impacts judgment, memory, decision making, emotional response, reaction time and more. But sleep isn't just for your brain. It’s also the time your body repairs tissue, balances and releases hormones, builds up energy for the following day, and rests.
So it’s unfortunate that sleep is often the first thing we cut when things get busy. Not only do we feel worse the next day, but anything replacing sleep (work, exercise, etc) doesn’t get done very effectively. And neither does anything else we do over the next 24 hours.
As if that wasn’t enough, lack of sleep also impacts how you eat.
Hungry, hungry hormones
Ghrelin is your hunger hormone, released by your stomach to tell your brain you’re hungry.
On an ordinary day, ghrelin levels look something like this:
This still happens when you haven’t had enough sleep, but on a grander scale. Multiple studies have shown ghrelin levels increase so you feel hungrier than usual when you wake up (likely to make up for the energy you didn’t get from your shortened sleep). As a result, you want larger portion sizes for breakfast and more snacks later in the day.
One day of eating extra isn’t that big of a deal. But when it happens chronically, that adds up to thousands more calories than you actually need over the course of a year. And that can have a big impact on your weight.
Leptin gets low
Ghrelin isn’t the only hunger-related hormone impacted. There’s also leptin.
Leptin is a hormone released by your fat cells to let your body know you have enough stored energy. In short, it curbs your appetite when you’ve had enough to eat.
If everything’s functioning normally, leptin should go up as ghrelin goes down to signal you’re full.
But your sympathetic nervous system (aka fight-or-flight mode) can suppress leptin levels when it’s constantly in control and prevent your parasympathetic nervous system (aka rest-and-digest mode) from activating.
The two nervous systems work together like a teeter-totter, one becomes more active as the other becomes less active. And your sympathetic nervous system always gets priority when you’re stressed, whether that comes from a saber-tooth tiger or lack of sleep.
Between the increased ghrelin and the decreased leptin, you have the perfect recipe for increased hunger throughout the day.
Speaking of stress...
A more active sympathetic nervous system also increases the amount of cortisol in your system at night.
Cortisol is your stress hormone and is supposed to be elevated in the morning to wake you up and slowly decrease throughout the day until its lowest level at night.
It’s also a regulator of insulin (that hormone that lowers your blood sugar).
When your blood sugar drops too low, cortisol is released to make insulin less effective. That way your blood sugar has a chance to get back into the normal range.
This backfires though when cortisol is constantly high. Over time, your body has to release more insulin than usual to fight cortisol and keep your blood sugar from building up too much in your blood cells. This can lead to diabetes, that point where your liver’s unable to produce the amount of insulin needed to keep your blood sugar in check.
Bring on the munchies
All of this becomes a double whammy when sleep loss creates a stronger desire to eat unhealthy foods throughout the day.
One reason this seems to happen is that sleep loss boosts the endocannabinoid levels in your blood, which increases the desire to eat and the satisfaction you get from eating (particularly high-carb, high-fat foods in an effort to curb that hunger). This is the same process that happens when you smoke a joint and get the munchies.
With enough sleep, it’s easier to resist less healthy foods (or at least be satisfied with a smaller amount). But with boosted endocannabinoid levels and a higher ghrelin-to-leptin ratio, it’s much harder, if not nearly impossible, to stop.
How to get a better night's slee
If you’ve been having a hard time getting a restful night’s sleep, don’t worry. There are a lot of things you can do to get back on track.
1. Turn off your electronics at least half an hour before bed
This allows for a few things.
First, your mind can quiet down and your body can relax, both of which allow your cortisol levels to drop so you can sleep more easily.
The blue light from your screens also disrupts the production of melatonin which is crucial to being able to fall asleep and stay asleep.
Blue light mimics light produced by the sun and tricks your body into thinking it’s still daylight. This comes from screens such as your computer, your cell phone, and yes, your tv. You might think tv helps you fall asleep, but it also causes lower quality sleep, which means you’ll be exhausted even with eight hours.
Turning off your screens an hour before bed is the ideal goal, but for some people that’s a lot of screen-free time. So start with 30 minutes and increase from there.
2. Wake up without an alarm clock
Our wake time is dictated for us by work, school, kids, and more. But it’s still possible to wake up without an alarm clock at the right time.
First start with what time you need to wake up and set your bedtime 7.5 hours before that time.
Why 7.5? Most adults have between 4-6 90 minute sleep cycles during the night, so the average of that tends to be a good starting point.
Not everyone has 90 minute cycles and the number of cycles tends to vary depending on how much sleep you need. So the first few nights when you use this method, take note of whether you wake up well before or after your alarm clock. Then add or subtract 30 minutes to the time you go to bed according to whether you need less sleep or more sleep.
You might still want to set an alarm clock as a safety precaution, but eventually you’ll find that you’ll be able wake up just before your alarm. Not only will you sleep the right amount of time for your body, but you’ll also ensure you wake up during the lightest part of your sleep schedule which will boost your energy and alertness better than any cup of coffee.
3. Watch what you’re eating at dinner time
Sometimes the food you eat at dinner can have an impact on your sleep. Caffeine is the obvious one, but alcohol, spicy food, and even things like MSG have been known to disrupt sleep if you eat or drink them too late in the day. And for some people (like myself), having their carbs at dinner rather than at lunch helps them fall asleep more easily and makes them feel more energized in the afternoons.
If you’re having trouble sleeping or find that you’re consistently getting restless sleep, keep a food/sleep journal to see if you can find a pattern of what might be causing your sleep troubles. If you do, it doesn’t mean you have give up that food altogether. Just have it earlier in the day and save the food that’s easier to process for dinner time.
If you’d like more sleep tips, the National Sleep Foundation is a good starting place for information on sleep hygiene and how to set up an optimal sleep environment.
Also remember that you don’t need to stress if you get a bad night’s sleep every now and then. It happens to everyone. Hormone levels might be temporarily thrown off, but they’ll bounce back within a couple of days once you’re back on track.
Sleep, a healthy diet and exercise are arguably some of the most important things you can be doing for your health. They all impact each other and help you feel your best when combined on a regular basis.
As we start nearing the holiday season, remember that an all-around healthy foundation is the key to feeling great at a time that can be stressful for many (and to not feeling guilty on the days you want to indulge). If you’d like some help eating consistently clean, consider adding some Methodology meals to your weekly routine.
With nutritious, balanced meals that are designed to help you feel lighter and more energetic throughout the day, you’ll have the food part of health covered in as little as 5 minutes.