by In a recent study published in the journal Nutrition, researchers at the University of Northumbria, UK, explored the relationship between adherence to a ketogenic diet and various aspects of mental health, such as calmness, contentment, alertness and emotional well-being, in the general healthy population.
Study: Ketogenic diet is positively associated with mental and emotional well-being in the general population. Image Credit: Chinnapong
Background
The ketogenic diet, high in fats and low in carbohydrates, switches metabolism from glycolysis to fatty acid oxidation, providing alternative energy substrates for the body and brain. Historically used to treat and investigate epilepsy in neurodegenerative and neurodevelopmental conditions, its effects on the general population are less studied. More research is needed to clearly understand the long-term psychological effects of the ketogenic diet across different populations and conditions.
About the study
The current study involved two cohorts, each recruited through opportunity sampling on social media platforms, adhering to ethical standards set by Northumbria University and the Declaration of Helsinki. All participants gave informed consent before data collection began.
In cohort 1, individuals were recruited from February to October 2021. Participants in this group completed two online assessment tools: the Perceived Stress Scale (PSS-10) and the Bond-Lader visual analog scales (BL-VAS). The PSS-10 assessed a general perception of stress, with scores ranging from 0 to 40, indicating different levels of stress. The BL-VAS measured mood through 16 pairs of opposite moods, providing scores for alertness, contentment and calmness, using a sliding scale from 0 to 100.
Cohort 2 was assembled from January to July 2022 and used different tools for psychological assessment: the Depression Anxiety Stress Scale (DASS-21) and a 3-item loneliness scale. The DASS-21 includes three subscales for depression, anxiety, and stress, each scored on a severity scale from 0 to 3. The loneliness scale, rated from 1 to 3, helped identify levels of loneliness among participants.
Both cohorts used an online platform to share the same demographic, socioeconomic and nutritional data collection methods. Participants reported on a range of variables, including dietary habits assessed via a short-form food frequency questionnaire. This enabled a comparison of dietary patterns between those on ketogenic diets and other diets, taking into account the frequency of consumption of ketogenic and non-ketogenic food items. The data were analyzed for various psychological and nutritional metrics, examining differences and correlations within and between the groups.
Study results
In the study, cohort 1 initially recruited 361 participants, although exclusions were made for various reasons, including lack of consent and incomplete data entries, resulting in 260 participants completing the PSS-10. Further attrition occurred during the transition between survey platforms, leaving 147 participants who completed the BL-VAS. This cohort examined the differences in perceived stress and mood between those on a ketogenic diet and those on other diets.
Cohort 2 started with 399 participants and was reduced to 276 after similar exclusions. This cohort used the DASS-21 loneliness scale and 3 items to assess psychological well-being.
In terms of demographics and socioeconomic factors, Cohort 1 showed significant differences in age and Body Mass Index (BMI) between the ketogenic and other diet groups. The ketogenic participants were generally older and had a higher BMI. Among the notable findings were higher cases of high blood pressure among ketogenic diet participants. Dietary patterns showed that people on the ketogenic diet eat more “ketogenic-friendly” foods and less “non-ketogenic” foods than their counterparts.
Cohort 2 showed similar age and health differences, with ketogenic participants again older but no significant differences in BMI between groups. Health ratings and dietary habits followed patterns similar to Cohort 1, with ketogenic participants reporting better subjective health and stricter adherence to ketogenic dietary guidelines.
Psychologically, the results of Cohort 1 showed that participants on a ketogenic diet reported better mood and lower stress levels than those not on the diet, with significant differences in alertness, satisfaction and relaxation. These differences persisted even after adjustment for demographic and health-related covariates.
Cohort 2 also found that participants on a ketogenic diet reported lower levels of depression, anxiety, stress, and loneliness. However, the improvements in loneliness were not statistically significant when adjusted for covariates.
In addition, the duration of adherence to the ketogenic diet showed positive correlations with psychological benefits in both cohorts. However, there was no significant correlation between the actual level of ketosis measured and psychological outcomes, suggesting that the duration of diet consistency may have a greater influence than the immediate metabolic state.
Conclusions
In summary, the study hypothesized that a ketogenic diet would enhance psychological well-being, which the results supported. Participants on the diet reported much better calmness, satisfaction, alertness and a reduction in stress, depression and anxiety. Although loneliness improvements were insignificant after adjustment for demographics, diet duration was correlated with increased benefits. Additionally, the study suggests that a ketogenic diet may improve mental health through mechanisms similar to anxiety medications.
