Keto Diet & Sleep

In a study published in the latest edition of the academic journal, Sleep Medicine, a group of ten researchers from various universities conducted a one-year experiment to test the effects of nutritional ketosis on the sleep quality of a group of individuals with either diabetes or pre-diabetes.

How the Study Was Done

This was a one-year study comprised of 465 participants, between the ages of 21 and 65, divided into three groups:

  • Group 1 — 262 individuals with type 2 diabetes and a BMI (Body Mass Index) over 25
  • Group 2 — 116 pre-diabetics with a BMI over 30
  • Group 3 — 87 type 2 diabetics who were already receiving the standard care for diabetes and who would act as the study controls

Groups 1 and 2 were instructed on how to achieve and maintain ketosis through carbohydrate restriction. They were given access to a mobile app and encouraged to use it daily to input their weight, blood glucose and blood beta-hydroxybutyrate (a ketone body produced during ketosis) concentrations.

No changes were made to the diets or care that Group 3 received.

The sleep quality of all three groups was measured at the beginning of the study and at the one-year conclusion of the study, using the Pittsburgh Sleep Quality Index (PSQI) questionnaire.

The PSQI consists of 19 questions, measuring the subject’s:

  • Subjective sleep quality
  • Sleep latency (the time it takes to fall asleep)
  • Sleep duration
  • Habitual sleep efficiency (the ratio of total sleep time to time in bed)
  • Sleep disturbances
  • The use of sleep-promoting medication (prescribed or over-the-counter)
  • Daytime dysfunction

What the Study Found

The researchers found overall sleep improvement in both of the groups who followed the ketosis-inducing diet but not in the control group (who continued to follow the diet recommended by their healthcare providers).


  • Group 1 showed significant improvement in their PSQI scores, going from an average of 7 at the beginning of the study to 6 at the one year mark. (A lower PSQI score indicates better overall sleep quality.)
  • Group 2 (the pre-diabetics) showed even greater improvement, dropping their PSQI scores from an initial average of 7, to 5 at the end of the study.
  • There was no change in the average PSQI score for the Group 3 individuals.

Here’s how the researchers summarized their overall conclusions, “Improved patient-reported sleep quality as assessed by global PSQI suggests that CCI (continuous care intervention) including nutritional ketosis benefited sleep quality in both patients with T2D (type 2 diabetes) and prediabetes. The proportion of patients categorized as “poor sleepers” at one year was significantly reduced in the CCI groups but not in the UC (usual care) group.”


It’s well documented that diabetics suffer from increased rates of sleep disturbance compared to the general public. This study claims that up to one third of diabetics suffer from a sleep disorder compared to 8.2% of non-diabetics.

Given how important sleep is to our health and wellbeing — and particularly so for those living with a major disease, such as diabetes — this study offers important information for those looking to improve their quality of life.

Learn More

You can review the complete study here.

(Please review our important Medical Disclaimer here.)

Photo by Toa Heftiba on Unsplash