A lot of today’s go-to diets emphasize protein and fat while minimizing carbohydrates. But different eating plans combine these macronutrients in different ways. There isn’t a one-size-fits-all diet. So to navigate sleeping well alongside a new eating plan, let’s take a quick look at two of the most popular eating plans, and what they entail.
The Ketogenic Diet
A ketogenic diet (or “keto”) focuses on eating fat while severely limiting carbohydrates to put the body in a state of ketosis. In ketosis, our bodies begin to aggressively burn fat for fuel. The standard keto eating strategy is typically 75% fat, 20% protein, and 5% carbohydrates. A modified, high-protein version of keto adjusts the ratio to 60% fat, 35% protein, and 5% carbs.
You might know someone who has tried a ketogenic diet and been thrilled with its weight loss benefits. Studies show that eating on a keto regimen is effective in helping people lose weight. But ketogenic diets are also being used to help resist disease. Studies show ketogenic diets can drastically lower blood sugar and improve insulin resistance, helping to improve diabetes and prediabetes.
Research indicates that ketogenic diets can improve markers for heart disease, including cholesterol and blood pressure. And keto is being increasingly studied as a dietary therapy for epilepsy, cancer, and neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
What you eat on a ketogenic diet: Meat, eggs, fish, full-fat, grass-fed dairy and unprocessed cheese, oils including coconut and olive, nuts and seeds, low-carbohydrate vegetables.
What you avoid on a ketogenic diet: Grains, almost all fruits, beans, root vegetables, sugar, alcohol.
The Paleo Diet
Paleo has been pretty popular for several years now. This eating plan is based on the premise that the healthiest diet is one that sticks close to what our ancient human ancestors consumed. That means unprocessed foods, like lean meat, fruits, and vegetables, and excludes dairy products, grains, and sugars. Unlike keto, a Paleo diet doesn’t lay out specific ratios of fat, protein and carbohydrates. That’s up to you, as you eat from a selection of approved foods. In practice, Paleo eating often tends to skew pretty low-carb. When you’re eating paleo, your carbohydrates come mostly from plants, and not from grains or sugars.
We haven’t seen an abundance of research on paleo eating. But studies have shown a paleo diet can improve blood sugar and insulin sensitivity, lower blood pressure, cholesterol and other markers of heart disease, and help people lose weight. Paleo diets have also been shown to reduce waist circumference, which is associated with heart disease, diabetes and sleep problems, including obstructive sleep apnea.
What you eat on a paleo diet: Meat, fish, eggs, vegetables, fruit, nuts, seeds, coconut, olive and other healthful oils.
What you don’t eat on a paleo diet: Sugars, grains, legumes, dairy (some paleo eating plans may incorporate full-fat dairy), many vegetable oils, any processed foods or ingredients.
How Keto & Paleo Diets Affect Sleep
Now that we know what some popular diets are about, let’s take a look at how they might affect your sleep. While there is a body of research that looks at the relationships of diet, macronutrients, eating patterns and sleep, there’s a relative lack of scientific study that explores how specific diets affect sleep. The Mediterranean diet is among the most well studied, and has shown broad benefits for health and longevity, as well as specific benefits for sleep.
We’re also missing long-term studies on the effects of diet and macronutrients on sleep. Much of the research is limited to short-term investigations of how different combinations and amounts of carbohydrates, proteins and fats affect our sleep patterns.
That said, there is scientific research that is contributing to an emerging picture of how ketogenic and Paleo diets may impact our sleeping lives. There are a number of studies in progress that explore these now-popular diet trends in relation to sleep and other measurements of health. And other research that examines the effects of macronutrients—carbohydrates, proteins, and fats—can help shed light on what to expect from your sleep when using these dietary plans.
A small number of studies show the keto diet may offer benefits for sleep, both through weight loss and other pathways. A just-released study on the effects of keto found that adhering to this eating plan helped reduce daytime sleepiness in a group of obese patients. Previous studies have found similar results, along with increases to REM sleep. Other research has shown ketogenic diets increase REM sleep and sleep quality in a group of children with epilepsy.
There’s some very interesting emerging research showing that ketogenic diets have an effect on a brain chemical that is important to sleep regulation: adenosine. Adenosine builds up in the body throughout the day, decreasing wakefulness as the day goes on and eventually promoting deeper slow-wave sleep at night. Studies show a ketogenic diet promotes adenosine activity in the body, helping to relax the nervous system, as well as reducing pain and inflammation—all of which can help improve sleep. We need to see more research to better understand the relationship of ketogenic diets to adenosine, and to sleep directly.
Research on the effects to sleep of high-protein diets is mixed. Studies show consuming greater amounts of protein is linked to longer sleep times, more consistent sleep patterns, and higher sleep quality. Recent research indicates that high-protein diets in people who are overweight may lead to improvements to sleep.
Studies on the effect of carbohydrates has also been mixed. Some research has shown people with sleep disorders such as insomnia and sleep apnea tend to consume less carbohydrates than people without these sleep disorders. However, other research shows reductions to slow-wave sleep in people who consume high-carb diets, compared to low-carb.
Generally, diets that derive their carbohydrates from healthy, fiber-rich whole foods are associated with better sleep. The Mediterranean diet, which emphasizes whole foods, lean proteins, fresh vegetables and fruits, a moderate amount of grain, is linked to improvements in insomnia and other sleep problems. The effects on sleep when changing your diet may depend heavily on the types of carbohydrates you eat, especially in the evening.
Potential Sleep Issues
It’s not uncommon to hear people report sleep problems when they start a new diet. A big reduction in carbohydrate intake can cause changes to sleep patterns. Some research suggests following a keto diet can improve sleep quality, while other studies show high-fat diets are linked to more disruptive sleep and trouble falling asleep.
It’s tough to find research that specifically addresses the Paleo diet and sleep issues. From talking with my patients, I know people who start eating paleo sometimes have a harder time sleeping, similar to people who adopt a ketogenic eating plan.
The shift away from carbohydrates and toward protein may explain these sleep issues. Carbohydrates increase levels of the tryptophan in the brain, which helps facilitate sleep. Protein, on the other hand, increases levels of tyrosine, an amino acid that triggers the production of stimulating brain chemicals, including epinephrine and norepinephrine. By limiting carbohydrates, while at the same time elevating the alertness, individuals may experience difficulty falling asleep and getting a full night of rest.Shop the Best Mattresses of 2023
Takeaways on Low-Carb Diets and Sleep
A diet that helps you get safely to a healthy weight and stay there will benefit your sleep. Your risks for obstructive sleep apnea and other sleep disorders will go down. You’ll sleep more comfortably, and wake with more energy for the day. But keep this in mind: losing weight at the expense of a sound, consistent sleep routine is not a smart strategy. The key is to identify the eating habits that allow you to lose excess weight, maintain a healthy weight, and sleep well at every step along the way.
Our eating and sleeping lives are deeply connected. What and when we eat affects our circadian rhythms, our gut health, our energy levels, and the hormones and biochemicals that stimulate and sedate us. If you’re starting on a new diet, be aware your sleep may change at first. Be prepared to pay extra attention to how you’re sleeping. If sleep issues arise in connection with a new diet and don’t ease after a few weeks, take a look at modifying your eating strategy in consultation with your doctor, to improve your rest.