Study finds ketogenic diet effective in treating anxiety, depression and other mental illnesses

Recent Nutrients This journal study examines the potential beneficial effects of the ketogenic diet (KD) on anxiety, depression, stress, schizophrenia, and bipolar disorder.

study: Potential effects of the ketogenic diet in the prevention and concomitant treatment of stress, anxiety, depression, schizophrenia, and bipolar disorder: from basic research to clinical practice. Image credit: artem evdokimov / Shutterstock.com

Health benefits of KD

The KD is characterized by low carbohydrate, high fat, and moderate protein, accounting for 5–10%, 65–80%, and 20–25% of total energy, respectively. Several studies have demonstrated the benefits of the KD in managing various medical conditions.

For example, the KD offers potential benefits in cancer treatment, cardiovascular health, and reduced inflammation. Additionally, the KD has been associated with both neuroprotective and anti-inflammatory effects, potentially preventing and simultaneously treating a range of psychiatric disorders.

Conventional treatments for managing psychiatric disorders include psychotherapy, pharmacological therapy, or both, all of which can have unwanted side effects for some patients. Therefore, there is an urgent need to develop new treatments that offer better outcomes and better tolerability.

About the Research

In this study, we conducted an extensive literature review on the beneficial effects of KD on stress, schizophrenia, bipolar disorder, anxiety, and depression. For this purpose, we carefully searched scientific databases such as Scopus, PubMed, and Web of Science using efficient and representative keywords to identify appropriate animal and clinical human studies.

These keywords included “ketogenic diet and anxiety”, “ketogenic diet and psychiatric illness”, “ketogenic diet and psychiatric disorders”, “ketogenic diet and neurobiological effects”, “carbohydrate or calorie restriction”, etc. Articles published in English were included in the analysis, but those published in non-peer-reviewed journals, commentaries, and editorials were excluded.

research result

Across different psychiatric disorders, KD interventions have both similarities and differences in treatment effectiveness.

Overall, animal studies have demonstrated that the KD effectively relieves symptoms of anxiety, depression, stress, bipolar disorder, and schizophrenia. Although animal studies have shown beneficial effects of the KD on depression, the available clinical evidence remains mixed.

The discrepancies in results may be due to differences in sample size, study design, participant characteristics, intervention duration, and heterogeneity of depressive disorders among human patients. Therefore, randomized controlled clinical trials and large-scale studies are needed to determine whether KD is effective as a treatment for depression.

Similar differences were found between animal and clinical studies regarding the anxiolytic effects of KD. Although clinical studies reported reduced anxiety after KD intervention, not all studies showed significant improvements. In addition to improving the heterogeneity of study designs, further research is needed on the molecular mechanisms by which KD exerts its anxiolytic properties.

The relationship between a KD and stress responses is complex. One study reported increased adrenal sensitivity and corticosterone levels in rodents fed a KD, while another documented improved cognitive performance and metabolic parameters in rats fed a KD exposed to chronic stress. Overall, these results highlight the complex connections between behavior, neuroendocrine pathways, and metabolism.

In the case of schizophrenia, the KD has been shown to have beneficial effects in both animal and clinical studies.

Evidence regarding the efficacy of KD in treating bipolar disorder is still lacking: some studies have reported reduced symptom severity and improved mood stability, but the robustness of these results needs to be established using larger randomized clinical trials.

Current research investigating the impact of KDs on psychiatric disorders has adopted a variety of approaches: for example, some studies have investigated the complex relationship between sleep, psychiatric disorders, and brain metabolism, while others have assessed the impact of KDs on depressive symptoms, cognition, social behavior, eating behavior, and anxiety-related behavior.

Conclusion

Although there is some evidence that KDs play a beneficial role in treating psychiatric disorders, further studies are needed to establish their clinical usefulness. The main limitations of the current study may be the presence of bias due to differences in methodology used in the reviewed studies and the limited availability of long-term follow-up data.

Therefore, future studies should mitigate the methodological limitations of existing studies, optimize treatment protocols, and investigate the molecular mechanisms by which KDs affect psychiatric disorders. Additional studies are also needed to establish the safety and efficacy of KDs in psychiatric treatment.