Why Can’t I Sleep? Part Three: How Diet Can Affect Sleep
This is the third and last post in my series on insomnia. Today I want to talk about how diet can sabotage your chances of getting a good night’s sleep.
Some of what follows will be glaringly obvious, but hopefully you’ll find something here that you didn’t know before.
I’ll be dividing today’s post into five categories:
- Food and drink that stimulate your nervous system
- Food and drink that cause acid reflux
- Food that is strongly flavored
- Food and drink that affect blood glucose
- Food and drink that irritate your digestive tract or harm your beneficial gut flora
Now, let me say at the start that we are all different. What affects the sleep of one person may have no effect whatsoever on another. Many of us have particular foods that disturb the quality of our sleep and we’ve learned to stay away from them through trial and error.
Because of this, there is no way I can possibly cover all the dietary items that may be causing your insomnia. However, there are a number of foods or dietary practices that are problematic for large numbers of people and that is what I want to cover in today’s post.
So with that disclaimer out of the way, let’s delve right in.
Food and Drink That Stimulate Your Nervous System
I’m sure some of you have made the mistake of ingesting caffeine too close to bedtime and paid the price for it. As many of you know, caffeine is a pretty powerful stimulant which is why so many start their day with a cup or two or three or…
Besides coffee, caffeine is also in tea, various soft drinks, energy drinks and chocolate. So having some before bedtime is not usually a good idea if restful sleep is your goal but most of you know that already.
Less obvious stimulatory foods are those containing excitatory amino acids; amino acids being the building blocks of protein. The two most problematic amino acids are aspartic and glutamic acid. Both are stimulating neurotransmitters, and in large amounts can overstimulate nerve and glia cells in the brain.
All meat, fish, poultry, dairy, legumes (including soy), wheat, seeds, seaweed and some dried fruit are rich sources of aspartic acid as is the artificial sweetener aspartame.
Glutamic acid is also found in meat, fish, poultry, dairy, eggs, legumes, wheat and of course monosodium glutamate (MSG).
I don’t recommend you eat less than three to fours hours before going to bed to give your body a chance to digest its food and avoid having any of these excitatory amino acids affect your sleep.
However, if you find that eating a protein-rich dinner prevents you from getting sleepy, you may want to experiment eating the majority of your protein earlier in the day to see if that helps or cut down your portions of protein at dinner.
Food and Drink That Cause Acid Reflux
I’m not going to spend any time on this because I’ve already covered this in part five in my small intestinal bacterial overgrowth (SIBO) series which you can read here. Suffice it to say that if acid reflux keeps waking you up in the middle of the night, getting a good night’s sleep is going to be an ongoing chore. Implementing the dietary changes I outlined in that post should help ease or eliminate this problem.
Foods That Are Strongly Flavored
Allium foods are the genus of foods that contain all edible onions like white, yellow and red varieties, scallions, garlic, chives and leeks. The problem for many is that when these foods are eaten raw, their taste can linger for a long time and bother you when you go to bed at night.
Even though I credit raw garlic for curing my SIBO, the taste of garlic in my mouth, especially at night, was not an exactly pleasant experience. Nor do raw onions agree with me.
This is unfortunate. As I wrote in my post What Are Prebiotics And Why You Should Care, these raw foods are very high in natural prebiotics which feed your beneficial colonic gut flora.
However, knowing that won’t do you much good if eating them causes you to burp them up all night and affect your sleep. These foods can also cause uncomfortable levels of gas when fermented by these very same bacteria.
That’s a big reason I’d rather take my daily dose of prebiotic powder instead of getting my soluble fiber in food. I find it doesn’t result in excess gas like food-based prebiotics.
Food and Drink That Cause Swings in Blood Glucose
It’s not my intention to dump on carbohydrates here. If you’re not a diabetic and have a fully functioning pancreas and liver, I see no reason to limit non-gluten and non-nightshade carbs like rice, corn or most starchy tubers. Nevertheless, high-glycemic carbohydrates do spike insulin levels and this does affect alertness.
Cortisol and insulin work in opposing directions so when insulin shoots up in reaction to a food or drink high in glucose like one containing refined carbohydrates, both cortisol and blood-glucose levels go down and this can make you feel very drowsy, which is not so great during the day if it causes you to nap unintentionally.
I know many of you have experienced sleepiness after eating a high-carb lunch once the glucose sugar rush comes to an end like our friend Alice in the photo above. Additionally, gluten grains like wheat, have a number of other compounds that can result in overwhelming tiredness, which I’ll cover shortly.
Every so often I catch a matinée performance of a live theater production. It’s surprising how many of the patrons fall asleep as soon as the lights go down and snore away during the performance. It’s obvious to me that they ate a very carb-heavy lunch before the show. Many of these slumbering patrons of the arts are going to have a hard time getting to sleep later that night as napping will likely interfere with getting to bed at a reasonable hour.
If daytime tiredness or napping is an issue for you, cut down on the quantities of carbohydrate you eat at breakfast and lunch.
On the opposite spectrum, glucose deficiency can cause problems after you’ve gone to bed. This can happen on very low-carb or ketogenic diets or in those with diabetes.
To maintain proper glucose levels, your body will either need to get it from food or your liver will need to make it from non-carbohydrate sources like pyruvate, lactate, glycerol or certain types of amino acids. This metabolic pathway is called gluconeogenesis and is an absolute necessity to keep blood glucose from falling to dangerous levels.
The problems begin if these glucose precursors are not available in sufficient quantities or your liver, for whatever reason, is not efficient or healthy enough to keep up with the body’s demand for glucose.
If your blood glucose falls too far during sleep, cortisol will kick in to raise it and likely wake you up in the process. I remember an interview a few years back where Gary Taubes, author of Good Calories, Bad Calories and a proponent of low-carb diets, told the interviewer how he would sometimes wake up at night and eat. I suspect this was his problem.
One way to tell if you are glucose deficient is to check for changes in saliva, mucus and tear production. Do you have a constantly dry mouth or nose? Are your eyes very dry, especially first thing in the morning? If so, you may need to increase the amount of glucose in your diet.
Also recall that a deficiency in mucus production in the intestine is ill-advised as it, along with the cells lining your digestive tract and your beneficial gut flora, serves as part of an important barrier defense against endotoxins and other antigens from your intestinal lumen.
For more on glucose deficiency, please see this series of posts by Paul Jaminet over at the Perfect Health Blog.
Food and Drink That Irritate Your Digestive Tract or Harm Your Gut Flora
I’ve covered this topic in-depth in my SIBO series but today I’ll focus on how these foods specifically affect sleep.
As I wrote in part one, nothing disrupts my sleep more than overindulging in alcohol. Oh how I wish this weren’t so as I do enjoy my tipple from time to time. Nevertheless, I enjoy a good night’s sleep more so I’ve really cut down on my alcohol consumption.
Binge drinking causes sleep problems for a number of reasons. While it may indeed make you drowsy enough to sleep, intentionally or not, it has a bad habit of waking you up a short while later.
Alcohol is extremely dehydrating so you’ll often wake up in the middle of the night with your tongue glued to the roof of your mouth. Quenching that thirst can be an issue. Add in a pounding headache and restful sleep becomes even more difficult.
Then there’s the toxic metabolite of alcohol, acetaldehyde. This is a particularly nasty and carcinogenic substance. It, along with alcohol, are toxic to bacteria, both good and bad so it should shock no one that alcoholics and binge drinkers are known for having both oral and gut dysbiosis.
Large quantities of alcohol cause intestinal inflammation and therefore increases leaky gut. And as you all know by now, increased intestinal permeability means an increased chance for endotoxins and antigens from your gut to enter the portal vein flowing to you liver.
So now imagine your poor liver not only having to metabolize the alcohol you just drank, but simultaneously having to detoxify all the bacteria, yeast or whatever else happens to cross the gut wall. As we learned in the last post, this inflammation will increase both cortisol production and the liver’s synthesis of indoleamine 2,3 dioxygenase (IDO) and its two toxic metabolites: 3-hydroxy-kynurenine (3-OH-KYN) and quinolinic acid (QUIN).
As explained here, this inflammation can be mitigated somewhat by strengthening gut barrier function with Lactobacillus supplementation, but it won’t prevent the other sleep disturbing properties of alcohol like dehydration, headache or acid reflux.
High Fiber Foods
If gas and bloating are a reason you can’t sleep at night, you may want to steer clear of high-fiber foods before turning in for the night. Fiber gets fermented in the colon and a byproduct of this is copious amounts of gas. If you couple this with the gut paralyzing effects of gluten, you risk bloating and painful stomach distension.
Apart from whole grains and legumes, I would also include cruciferous vegetables on this list. This family of vegetables includes cauliflower, cabbage, bok choy and broccoli. These are very nutritious and health-promoting foods but high in fiber that your colonic bacteria loves to ferment. You may want to eat them earlier in the day and not at dinner.
This plant family includes tomatillo, all peppers including bell pepper, potato, tomato and eggplant. Edible nightshades contain alkaloids that can be very irritating to the gastrointestinal mucosa, and because of this are implicated in gut-wall inflammation and leaky gut.
Now that I have given up gluten and cut back on drinking alcohol, the number-one dietary reason I have trouble getting to or staying asleep is because I had too many nightshades for dinner. I love potatoes but apparently they don’t love me back as they disturb my sleep unlike other starchy tubers like sweet potatoes or yams. A lot of people are also very sensitive to peppers especially as they age.
If you’ve given up eating gluten and have reduced your intake of alcohol but still have sleep issues, consider cutting nightshades out of your diet or at the very least, avoiding them at dinner to see if that helps.
Excess Dietary Fructose
Fructose makes up half of the sucrose or sugar molecule. Also found naturally in fruit and maple syrup, it’s what is responsible for the sweet taste of sugar. Fructose is quickly transported to the liver because it is quite damaging to protein structures in the body, readily forming advanced glycation end products or AGEs.
Fructose has the unique property of rapidly breaking down adenosine triphosphate or ATP in cells that use oxygen, including those cells capable of absorbing fructose in the digestive tract. By doing so it also rapidly elevates reactive oxygen species or free radicals to a point that overwhelms the cell’s built-in defenses to neutralize them.
Getting your fructose from fruit is normally not an issue because it comes packaged with fiber, antioxidants and vitamins that help counteract its oxidizing effects on cells while limiting the amount you can eat. While eating two apples can be quite satiating, removing its fiber and making juice from it can allow you to easily drink the fructose equivalent of four or more apples at one go.
Getting your fructose from refined sources like sugar and high fructose corn syrup is even worse as not only is it devoid of fiber that might limit its ingestion, it is also devoid of any antioxidants that might counter its ill effects on intestinal cells. As it increases oxidation and inflammation in the small intestine, it will promote the growth of pathogens by reducing beneficial Lactobacillus bacteria. Fructose will also reduce colonies of bifidobacteria in the colon. Refined sugars should be limited to avoid promoting endotoxemia and disturbing sleep. Eating that piece of cake or pie after dinner may not be such a good idea after all.
Omega 6 Vegetable Oils
In the gut, excess omega 6 fatty acids will increase oxidative stress and inflammation thus promoting endotoxemia. Polyunsaturated oils are extremely prone to forming free radicals when exposed to heat and high pressure. As most industrial seed oils are produced using both, they are already full of free radicals when you buy them.
If used for cooking, the damage is compounded further. Eating foods cooked in these types of oils is therefore to be avoided. By their very chemical structure, saturated fats are the most stable to heat and resistant to oxidation, followed by monounsaturated fats like olive oil. Avoiding foods with excess omega 6s in them is therefore recommended if you have sleep issues.
Omega 3s, on the other hand, are anti-inflammatory and may help calm your digestive tract in the absence of other inflammatory substances like alcohol, gluten, fructose and omega 6 vegetable oils. However, I recommend you obtain your omega 3s in whole foods rather than in a capsule. Knowing what I know about how nutritional supplements are handled in warehouses and in transit, taking fish oil capsules is a bit of a gamble due to their very delicate structure.
Ah, gluten, my absolutely favorite dietary whipping boy. It’s been a while since I’ve been able to rack it over the coals so let me gleefully dive right in!
I could write a book on gluten and many people already have. It appears to be a growing cottage industry and I’m pleased that it’s garnering so much deserved attention.
Gluten grains are really quite fascinating when it comes to sleep. Speaking from personal experience, nothing apart from binge drinking, induces drowsiness like eating gluten grains, especially when combined with sugar.
This is interesting as gluten is high in excitatory glutamic and aspartic acid, so you would think the opposite would be true. It’s glutamic acid, by the way, that makes so many freshly baked wheat products pop in your mouth with flavor.
There are several reasons for this. Gluten releases five different opioid protein fragments or peptides when digested: A4, A5, B4, B5 and C. Besides their well-known pleasurable and addictive properties, opioids are quite sedating. Beds figured prominently in opium dens for a reason. These opioid peptides put the “comfort” in comfort foods.
One gluten opioid, A5, stimulates insulin production. So not only does the carbohydrate portion of gluten grains promote the release of insulin, so too its protein content.
Along with gluten opioids, another compound called adenosine is also produced. Adenosine is a calming neurotransmitter that slows not only digestive peristalsis, but pretty much all neuronal circuits.
Finally, wheat germ agglutinin (WGA), gluten’s quite ingenious natural plant pesticide, binds readily to insulin receptors in fat and liver cells. In small concentrations, it enhances the actions of insulin in shuttling glucose into cells and out of the bloodstream. In larger concentrations, however, it prevents the binding of insulin to cell receptors thus inhibiting glucose from entering. This causes blood-glucose levels to rise further, which calls forth a more pronounced insulin response and subsequent blood sugar crash that results in intense sleepiness and/or hunger.
At Thanksgiving, it isn’t the turkey that’s making you sleepy after you eat. It’s all that gluten and WGA you just ate in the “healthy” whole-wheat bread rolls, stuffing, bread crumbs, gravy, cake, cupcakes and pie crust. The poor turkey has nothing to do with it.
So why not recommend eating gluten for an insomniac?
Because all of these tranquilizing properties mask its harmful effects on the gut wall. Moreover, as explained in my post on plant lectins, natural pesticides like WGA are likely toxic to our beneficial gram-positive gut flora. Eating gluten and WGA compromises gut barrier function and increases inflammation, which fuels insomnia. And since it also inhibits peristalsis, it predisposes to SIBO and all the negative effects on health that flows from that.
Now I’m a realist. Many of you reading this blog, especially those reading it for the first time, are probably not going to stop eating wheat.
Well let me recount a little family story. My spouse’s bother-in-law was complaining one day about how terrible his insomnia was, how his knees, joints and back ached, how he alternated between constipation and diarrhea and how bad his heartburn and acid reflux had gotten. When my spouse suggested that he consider cutting gluten from his diet to see if this might be causing his problems, he agreed that might be the issue but then asked, “but at what cost?”
But at what cost indeed!
Apparently, the thought of giving up his bread, pasta, cookies, pancakes, waffles, wheat cereal, donuts, fried chicken, pizza, cake, pie, battered onion rings and other gluten-loaded, processed crap in a box—you know, everything that makes the standard American diet the sterling dietary achievement it is—was just too much of a price to pay for getting a good night’s sleep, being pain-free and preventing his body from collapsing under his considerable weight. Brilliant, absolutely brilliant!
This is an all too common viewpoint. However, even if you believe giving up gluten is too much of a sacrifice, ask yourself what you’re sacrificing every time you don’t get a restful night’s sleep, not to mention the potential health consequences of compromised gut barrier function. Unlike the brother-in-law, you may choose to make the rational decision that forgoing these foods is worth more than a life filled with pain, acid reflux, heartburn, gastrointestinal upset, insomnia and other diseases lurking in the shadows. Just saying.
One other thing about gluten before I wrap this up.
Ever since I was a child, I suffered from an alarming sleeping disorder. On occasion, shortly after falling asleep, I would wake because I couldn’t breathe. I would quickly swing my legs over the side of the bed, sit up and push my fist into my stomach in a sort of self-administered Heimlich maneuver to open up my airways. You can imagine the anxiety it caused me and how fearful I became of going to bed or going back to sleep after an episode.
I could never isolate what it was that triggered this as it was totally unpredictable. Every doctor I asked suspected a reaction to some food but had no clue what it could be. And since I rarely ate right before bedtime, I didn’t even know where to begin looking.
When I finally gave up gluten at the age of 50 to treat my IBS, guess what? This life-long sleep disorder, along with my insomnia, disappeared and has never returned in the two years I’ve been gluten-free. Anytime I feel in the least bit tempted to eat something with gluten in it, all I have to do is remind myself of those terrifying episodes and the urge quickly passes.
I would be remiss if I didn’t mention that there are lots of legitimate reasons for not being able to sleep that are not related to behavioral habits or diet. Worry and the stress it provokes being number one on the list. Stress has terrible effects on our gut health and therefore sleep as I described in the previous post.
Not all worry is rational but a lot is. In an economy that has seen the lives of millions, both here in the United States and elsewhere, decimated by the worst economic crises since the Great Depression, there are lots of reasons many get no sound sleep. Watching someone you love battling a serious disease, experiencing the death of a friend or family member or experiencing the breakup of a relationship can all cause serious sleep disturbances.
The reality is that we live in a world where many of the factors that threaten our survival and happiness, both physical and economic, are outside of our control. No sleep hygiene suggestion, diet, supplements or blogger can change that. And until these external circumstances change, restful sleep may continue to be a rare commodity for many.
Please know that I’m very much aware of the larger societal context affecting sleep and disease in general. None of us can individually control these factors. All we can do is refrain from adding to the problem through our actions. I hope these posts help you do so.
I wish you all rejuvenating sleep and pleasant dreams.
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