When I did my first earnest attempt at a keto diet a few years ago, one of the benefits I quickly noticed was improved wakefulness and energy during the day. I chalked this up to sleeping better on keto.
It turns out that I might have been one of the lucky ones. While plenty of people report improved sleep, a fair number also complain of insomnia, sleep disruptions (waking frequently during the night), and generally poor sleep once they go keto.
Can a keto diet really impact sleep quality? What might be the mechanism behind a correlation? And how does one work around any potential effect?
I’ve written a lot about sleep over the years, and I don’t intend to rehash what I’ve already written. Rather, I want to explore why a very-low-carb ketogenic diet specifically might impact sleep. I’ll link to some of my past posts at the bottom for those interested in improving overall sleep hygiene.
Insomnia disorder, as defined in the DSM-5, involves the following:
Acute insomnia is similar, but it’s short-term and might be attributable to a specific trigger, such as a stressful event, major life change, or travel.
People who complain about “keto insomnia” seem to mean one of two things:
It can be hard to know whether the latter are actually related to keto at all. However, if diet is the only obvious change these folks have made, keto seemingly takes the rap.
On possible clue is this oft-cited study in which participants experienced decreased REM and increased slow-wave sleep when following a keto diet. Decreased REM sleep can contribute to the subjective experience of insomnia. However, total sleep was not impacted. This study was also small, involving 14 participants who followed a keto diet for just two days.
Other than that, however, there’s not much to go on. A couple studies found no change in sleep quality among healthy adults following a keto diet, and a handful of others reported improved sleep quality (in epileptic children and obese adolescents).
Moreover, the team at Virta Health recently released their findings after one year of treating diabetic and prediabetic patients with keto diet interventions. Their patients enjoyed significant improvements in sleep quality and daily functioning compared to baseline and compared to individuals who didn’t go keto.
All together, the research so far suggests that when it comes to sleep, keto is neutral-to-positive for healthy adults and beneficial for individuals struggling with certain health conditions. Of course, the data are still quite sparse.
A somewhat larger, but still limited, body of research has looked more generally at how the macronutrient composition of one’s diet affects sleep. To be blunt, the results of these studies are all over the map. There’s tremendous variation from study to study in terms of how diets were constructed or measured, food timing, other relevant dietary factors such as total calorie intake and fiber content, as well as what aspects of sleep were assessed and how. Depending on which study you’re reading, consuming fat, protein, or carbohydrates might seem to help, hurt, or have no effect on sleep.
In short, there’s no compelling scientific explanation for when or why keto would harm your sleep. I know this is no comfort to those of you who are experiencing sleep disruptions now, however. Let’s turn to some things you can try if you’re not in the camp of good sleep while keto.
Despite the dearth of research, it’s possible to make some reasonable guesses about what might be causing your sleep issues. Of course, before trying any of the supplement suggestions below, consult your doctor. Likewise, get help if your sleep is so poor that you are having trouble functioning.
First, the obvious: basic sleep hygiene. These are the things I harp on all the time, like avoiding blue light at night and honoring a consistent bedtime. Sure, you probably didn’t change any of these when you went keto. However, it might be that something about keto eating—like getting less tryptophan to your brain (I’ll explain in a minute)—is making you more sensitive to poor sleep habits. Refer to my other sleep posts linked below for more details.
Check your electrolytes. Especially if you’re new to keto, electrolytes are the most likely culprit for sleep issues. You want to aim for the following daily:
Most keto newbies drastically underestimate how important electrolytes are, not just for sleep but for energy, workout performance, and avoiding the keto flu. Check out this post for more details.
For sleep issues, start with magnesium. Make sure you’re including plenty of magnesium-rich foods such as leafy greens, dark chocolate, and hemp seeds in your diet. You can also supplement with magnesium—the glycinate form is preferred for sleep—starting with 100-400 mg as needed.
Also consider adding a mug of warm bone broth to your evening routine. Besides being soothing, it’s a great way to get sodium and the amino acid glycine. Glycine is the most abundant amino acid in collagen. Supplementing with 3 grams of glycine before bed has been shown to improve sleep.
Make sure you’re neither too hungry nor too full at bedtime. As you adjust to your new way of eating, try to avoid extremes of hunger in the evening. If you’re practicing intermittent fasting, make sure your fasting window isn’t leaving you stuffed or famished at when it’s time to hit the hay.
Dial back the caffeine. Is it possible you’ve been a little too enthusiastic about fatty coffee since going keto?
Get your stress in check. We all know that stress is a sleep killer, and I see stress running high in the keto community. Micromanaging macros, worrying about which foods are and are not “allowed,” trying to do too much too soon—keto folks can really get themselves worked up. If this sounds familiar, you need to take a step back and work on stress reduction.
Try adding a small amount of high-glycemic carbs to your dinner. Wait, what? Am I really telling you to eat more carbs on keto? Yes, for a good reason.
As you probably know, melatonin is the hormone primarily responsible for regulating your sleep-wake cycle. The amino acid tryptophan is a precursor of melatonin. In the brain, tryptophan converts to 5-HTP, then serotonin, then melatonin. To get into the brain, tryptophan relies on protein transporters, which also carry other amino acids across the blood-brain barrier. When there is too much traffic—that is, too many other amino acids trying to use the protein transporters—not enough tryptophan can get across.
Insulin shuttles those competing amino acids into muscles, leaving the roads clear for tryptophan so to speak. By adding some high-GI carbs to your last meal of the day, you bump up insulin and facilitate this process.
Now, I wouldn’t recommend this as your first option if you are brand new to keto. However, if you’re one of those people who is suddenly struggling with sleep after being keto for a while, this is worth trying. Michael Rutherford, NTP, Primal Health Coach, and moderator of our Keto Reset Facebook group says his clients have had good results adding ~20 grams of carbs to their last meal of the day. Potatoes or sweet potatoes are good choices.
If you just can’t bring yourself to eat more carbs, you can also supplement with tryptophan. A dose of 250-500 mg is a good place to start, increasing as needed. Chris Masterjohn recommends taking tryptophan on an empty stomach and as far as possible from other sources of protein.
Another possible workaround is to supplement with 5-HTP, which is a common ingredient in sleep aids. Rutherford advises his clients to start with 100 mg of 5-HTP taken 30-60 minutes before bed. Be cautious with this supplement if you have depression or anxiety.
Skip the middlemen and supplement melatonin. Melatonin supplementation is somewhat controversial. It’s not my first choice—I’d rather you start by addressing sleep hygiene and tweaking your diet—but I’m not opposed to supplementing as needed.
Doses as low as 0.5 mg can be effective, although as much as 5 mg is generally regarded as safe. I recommend starting at the bottom end, since lower doses are closer to normal physiological levels. Take melatonin at least an hour after eating your last food of the day.
Get your thyroid and cortisol levels checked. If none of your self-experimentation works, or if you’re having other signs of thyroid imbalance, get your thyroid function and cortisol levels checked. While I don’t believe keto is inherently bad for thyroid or adrenal health, it’s certainly worth a trip to your doc.
What’s your experience? Are you sleeping like a baby on low-carb/keto—or not? Have you found any solutions other than those suggested here? Comment below, and have a great week, everyone.
More sleep tips from Mark’s Daily Apple
Herrera CP, Smith K, Atkinson F, Ruell P, Chow CM, O’Connor H, Brand-Miller J. High-glycaemic index and -glycaemic load meals increase the availability of tryptophan in healthy volunteers. Br J Nutr. 2011 Jun;105(11):1601-6.
Levenson JC, Kay DB, Buysse DJ. The pathophysiology of insomnia. Chest. 2015;147(4):1179–1192.
Peuhkuri K, Sihvola N, Korpela R. Diet promotes sleep duration and quality. Nutr Res. 2012 May;32(5):309-19.
Riemann D, Spiegelhalder K, Nissen C, Hirscher V, Baglioni C, Feige B. REM sleep instability–a new pathway for insomnia? Pharmacopsychiatry. 2012 Jul;45(5):167-76.
Silber BY, Schmitt JA. Effects of tryptophan loading on human cognition, mood, and sleep. Neurosci Biobehav Rev. 2010 Mar;34(3):387-407.
St-Onge MP, Mikic A, Pietrolungo CE. Effects of Diet on Sleep Quality. Adv Nutr. 2016 Sep 15;7(5):938-49.