Effect of low-carbohydrate diet on depression and anxiety: A systematic review and meta-analysis of controlled trials

Complete remission of depression and anxiety using a ketogenic diet: case series

Background

There is little data that describe the use of ketogenic metabolic therapy to achieve full remission of major depression and generalized anxiety disorder in clinical practice. We present a retrospective case series of three adults with major depression and generalized anxiety disorder with complex comorbidity, treated with personalized ketogenic metabolic therapy, who achieved complete remission of major depression and generalized anxiety disorder and improvements in flourishing, self-compassion, and metabolic health.

Methods

Three adults, ages 32-36, with major depression, generalized anxiety, other anxiety disorders, and comorbid psychiatric conditions were treated for 12-16 weeks with personalized whole food animal-based ketogenic metabolic therapy (1.5:1 ratio) in a specialized metabolic psychiatry practice. Interventions included twice-weekly visits with an experienced ketogenic registered dietitian; daily photo journaling and capillary blood BHB/glucose/GKI monitoring; virtual groups; family/friends support; nature walks and talks several times per week, and community building. Successful adoption of the ketogenic diet was defined as the achievement and maintenance of capillary BHB ≥ 0.8 mmol/L and GKI < 6. Remission was assessed by GAD-7 and PHQ-9, and quality of life was assessed subjectively and with validated scales for flourishing and self-compassion. Metabolic health was assessed by laboratories/biometric measures.

Results

Two patients achieved remission of major depression (PHQ-9 ≤ 4) and generalized anxiety (GAD-7 ≤ 4) within 7 weeks of therapeutic nutritional ketosis; one required 12 weeks. Anxiety responded and remitted more quickly than major depression. Flourishing and self-compassion increased steadily. Patients lost 10.9 to 14.8% of their initial body weight within 12 weeks and improved metabolically; one achieved optimal metabolic health.

Conclusion

Complete remission of major depression and generalized anxiety disorder occurred within 7-12 weeks of therapeutic nutritional ketosis during treatment with a personalized animal-based ketogenic diet (ratio 1.5:1) in adults with complex comorbid depression and anxiety engaged in a specialized metabolic psychiatry program.

Low-carbohydrate-diet score, dietary macronutrient intake, and depression among adults in the United States

BACKGROUND

The aim was to ascertain whether low-carbohydrate-diet (LCD) score and dietary macronutrient intake are associated with depression.

METHODS

This cross-sectional study included 23,204 United States adults from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. Dietary macronutrient intake was evaluated by the average of two 24-h dietary recall interviews. LCD score was calculated by summing the 11 quantiles values of the percentages of energy derived from carbohydrate, protein, and fat. Major depression was defined as a nine-item Patient Health Questionnaire score of 10 or more. Logistic regression and restricted cubic spline models were used to explore the relationship between LCD score, dietary macronutrient intake, and depression.

RESULTS

LCD score was significantly associated with the risk of depression after adjustment for covariates (odds ratio, 0.98; 95 % confidence interval, 0.97-0.99; p < 0.001). Restricted cubic splines showed that the pattern of this inverse association was nonlinear. Among macronutrients, carbohydrate and protein intake was nonlinearly associated with the risk of depression, whereas fat intake was not related to the risk of depression. A decreased risk of depression was observed when the carbohydrate intake was moderate (45.3 %-59.1 %). The pattern of the association between protein intake and the risk of depression was L-shaped.

CONCLUSIONS

LCD score was inversely associated with the risk of depression in a nonlinear manner in a nationally representative sample of adults from the United States. Furthermore, moderate carbohydrate intake and high protein intake were correlated with a lower risk of depression.

Low-carbohydrate diet as a nutritional intervention in a major depression disorder: focus on relapse prevention

Objectives: Mood disorders are trending to be among the leading causes of years lived with disability. Despite multiple treatment options, around 30% patients with major depressive disorder (MDD) develop treatment resistant depression (TRD) and fail to respond to current pharmacological therapies. This study aimed to explore the potential benefits of nutritional treatment strategies, along with their molecular mechanisms of action, focusing especially on low-carbohydrate diet (LCHD), ketogenic diet (KD) and other strategies based on carbohydrates intake reduction.Methods: A comprehensive literature review was conducted to determine the impact of LCHD on alleviating depressive symptoms in patients with MDD, along with an explanation of its mode of action.Results: The study revealed significant impact of nutritional interventions based on restriction in carbohydrate intake such as LCHD, KD or sugar-sweetened beverages (SSB) exclusion on anxiety or depression symptoms reduction, mood improvement and lower risk of cognitive impairment or depression. The efficacy of these approaches is further substantiated by their underlying molecular mechanisms, mainly brain-derived neurotrophic factor (BDNF) which is a potential key target of sugar restriction diets in terms of neuroplasticity.Discussion: Healthcare professionals may consider implementing LCHD strategies for MDD and TRD patients to modify the disease process, maintain euthymia, and prevent depressive episode relapses. Ranging from the exclusion of SSB to the adherence to rigorous LCHD regimens, these nutritional approaches are safe, straightforward to implement, and may confer benefits for well-being and relapse prevention in this specific patient population.

Psychological aspects of rehabilitation nutrition: A position paper by the Japanese Association of Rehabilitation Nutrition (secondary publication)

Psychological aspects of rehabilitation nutrition affect physical, cognitive, and social rehabilitation nutrition. When depression is recognized, not only pharmacotherapy and psychotherapy, but also non-pharmacological therapies such as exercise, nutrition, psychosocial, and other interventions can be expected to improve depression. Therefore, accurate diagnosis and intervention without overlooking depression is important. Psychological aspects of preventive rehabilitation nutrition is also important because depression can be partially prevented by appropriate exercise and nutritional management. Even in the absence of psychological negatives, increasing more psychological positives from a positive psychology perspective can be useful for both patients and healthcare professionals. Positive rehabilitation nutrition interventions can increase more psychological positives, such as well-being, through cognitive-behavioral therapy and mindfulness on their own, as well as through interventions on environmental factors. Consequently, physical, cognitive, and social positives are also expected to be enhanced.

The Brain-Gut-Microbiota Interplay in Depression: a key to design innovative therapeutic approaches

Depression is the most prevalent mental disorder in the world associated with huge socio-economic consequences. While depressive-related symptoms are well known, the molecular mechanisms underlying disease pathophysiology and progression remain largely unknown. The gut microbiota (GM) is emerging as a key regulator of the central nervous system homeostasis by exerting fundamental immune and metabolic functions. In turn, the brain influences the intestinal microbial composition through neuroendocrine signals, within the so-called gut microbiota-brain axis. The balance of this bidirectional crosstalk is important to ensure neurogenesis, preserve the integrity of the blood-brain barrier and avoid neuroinflammation. Conversely, dysbiosis and gut permeability negatively affect brain development, behavior, and cognition. Furthermore, although not fully defined yet, changes in the GM composition in depressed patients are reported to influence the pharmacokinetics of common antidepressants by affecting their absorption, metabolism, and activity. Similarly, neuropsychiatric drugs may shape in turn the GM with an impact on the efficacy and toxicity of the pharmacological intervention itself. Consequently, strategies aimed at re-establishing the correct homeostatic gut balance (i.e., prebiotics, probiotics, fecal microbiota transplantation, and dietary interventions) represent an innovative approach to improve the pharmacotherapy of depression. Among these, probiotics and the Mediterranean diet, alone or in combination with the standard of care, hold promise for clinical application. Therefore, the disclosure of the intricate network between GM and depression will give precious insights for innovative diagnostic and therapeutic approaches towards depression, with profound implications for drug development and clinical practice.

Study of Different Personalised Dietary Plans on Eating Behaviour, Body Image and Mood in Young Female Professional Handball Players: A Randomised Controlled Trial

Low energy availability may precede or be caused by cognitive disturbances in professional athletes. Related psychological problems include disordered eating patterns, body shape preoccupation, depression or anxiety. The objective of this research was to evaluate the effects of different personalised dietary plans on psychological factors in young professional female handball players with low energy availability. This 12-week randomised clinical trial involved 21 female players aged 22 ± 4 years, 172.0 ± 5.4 cm and 68.4 ± 6.7 kg divided into three groups (FD: free diet; MD: Mediterranean diet; HAD: high antioxidant diet). Eating behaviour (Eating Attitude Test, EAT-26: diet, bulimia and oral control subscales), body image (Body Shape Questionnaire, BSQ) and mood state (Profile of Mode State, POMS: tension, vigour, anger, depression, fatigue) were assessed. All participants showed low energy availability (<30 kcal/lean mass per day). The different plans showed no significant differences between them but significant differences over time within groups for the variables: body image, Tension, Vigour and Depression (p < 0.05). Eating behaviour improved slightly but did not show statistically significant changes. Following an adequate nutritional planning for athletes seems to improve the mood and body perception of young female handball players. A longer intervention period is required to assess the differences between diets and improvement of other parameters.