It’s tough to find research that specifically addresses the Ketogenic diet and sleep. The shift away from carbohydrates and toward protein may explain these sleep issues. Carbohydrates increase levels of the amino acid tryptophan in the brain, which helps facilitate sleep when it converts to serotonin. Serotonin is necessary for the body to produce the sleep hormone melatonin. Protein, on the other hand, increases levels of tyrosine, an amino acid that triggers the production of stimulating, alerting brain chemicals, including epinephrine and norepinephrine. Reducing serotonin by limiting carbohydrates—while at the same time elevating the alertness-promoting chemicals associated with tyrosine—may result in difficulty falling asleep and getting a full night of rest.
Research on the effects to sleep of high-protein and high-carbohydrate diets is mixed. Some studies have shown people with sleep disorders such as insomnia and sleep apnea tend to consume less carbohydrates than people without these sleep disorders. Other research shows reductions to slow-wave sleep in people who consume high-carb diets, compared to low-carb.
One factor that seems clearly to matter when it comes to carbohydrate intake? Quality. Diets that derive their carbohydrates from healthy, fiber-rich whole foods—as opposed to sugars and processed starches—are associated with better sleep. The Mediterranean diet, which emphasizes whole foods, lean proteins, fresh vegetables and fruits, a moderate amount of grain—while minimizing sugars—is linked to improvements in insomnia and other sleep problems. The effects on sleep from moving from a high-carb to a low-carb diet may depend heavily on the types of carbohydrates you’ve been eating, the ones you keep in place in your new regimen, and the timing of your eating, especially in the evening.
High protein diets have also shown both benefits and drawbacks for sleep. Some studies show consuming greater amounts of protein is linked to longer sleep times, more consistent sleep patterns, and higher sleep quality. Other research suggests higher protein intake is linked to shorter sleep amounts. Recent research indicates that high-protein diets in people who are overweight may lead to improvements to sleep.
A couple takeaways on low-carb diets and sleep
There isn’t a one-size-fits-all message about how these popular diets affect sleep. To navigate sleeping well alongside any new eating plan, keep these things in mind:
Losing weight will help you sleep better. 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 also: 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.
Any dietary change can alter your sleep. 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.
There’s some exciting research coming on this topic, which we’ll return to soon. In the meantime, eat well and sleep well as we head into a fresh new year.
- Image by stine moe engelsrud from Pixabay