A modified Mediterranean dietary intervention for adults with major depression: Dietary protocol and feasibility data from the SMILES trial

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.

The Relationship between Diet, Depression, and Alzheimer's Disease: A Narrative Review

PURPOSE OF REVIEW

This narrative review evaluates the role of diet in the relationship between depression and Alzheimer's disease (AD).

RECENT FINDINGS

AD and depression are often comorbid, and depression appears to independently increase the future risk of AD. Evidence suggests diet influences the risk of both conditions directly and indirectly. Diet impacts neurochemical and biological processes that may affect the development and progression of depression and cognitive dysfunction. The dietary components offering the greatest protection against depression and AD are yet to be determined. Current evidence highlights the importance of polyphenolic compounds, folate, B vitamins, and polyunsaturated fatty acids, along with adherence to dietary patterns like the Mediterranean diet, which includes multiple beneficial dietary factors.

SUMMARY

The investigation of dietary factors in the prevention of depression and AD is a comparatively young field of research. Comprehensive highly characterised longitudinal datasets and advanced analytical approaches are required to further examine the complex relationship between diet, depression, and AD. There is a critical need for more research in this area to develop effective preventive strategies aimed at maintaining mental and physical health with advancing age.

Lifestyle modification as intervention for seasonal affective disorder: A systematic review

Bright light therapy (BLT) and pharmacological therapies currently represent the first line treatments for patients with seasonal affective disorder (SAD). Lifestyle modifications offer a diverse field of additional intervention options. Since it is unclear, if lifestyle modifications are effective in SAD patients, this systematic review aims to synthesize the current evidence on their effectiveness and safety. We systematically searched for randomized controlled trials (RCTs) assessing lifestyle modifications (nutrition, exercise, staying outdoors, sleep, social aspects, mindfulness methods) in SAD patients. We defined the primary outcome as the post-therapeutic extent of depressive symptoms, measured by validated psychiatric symptom scales. Due to the insufficient number of studies and the high heterogeneity of the interventions we were not able to calculate a meta-analysis. We identified 6 studies from the following areas of lifestyle modification: diet, exercise, staying outdoors, sleep and music therapy. All studies showed improvements of depression scores in the intervention as well as in the control groups. The risk of bias was rated as high for all studies and the certainty of evidence was rated as very low. The results point towards the possible effectiveness of the interventions examined, but due to the small number of studies found, too small sample sizes and methodological limitations, we cannot draw a valid conclusion about the effectiveness of lifestyle-modifying measures in SAD patients. Larger, high-quality RCTs are needed to make evidence-based recommendations and thus to expand the range of therapeutic options for SAD.

Delivery of a telehealth supported home exercise program with dietary advice to increase plant-based protein intake in people with non-alcoholic fatty liver disease: a 12-week randomised controlled feasibility trial

This study evaluated the feasibility and safety of a telehealth delivered exercise plus plant-based protein diet in adults with non-alcoholic fatty liver disease (NAFLD). This was a 12-week, randomised controlled feasibility trial including twenty-eight adults aged > 45 years with NAFLD randomised to a home muscle strengthening program (3 d/week) with increased protein intake (target ∼1·2-1·5 g/kg/d) from predominately plant-based sources and behavioural change support (3-4 text messages/week) (Pro-Ex n 14) or usual care (UC, n 14). Feasibility was assessed via retention (≤ 10 % attrition), adherence (exercise ≥ 66 %; recommended daily protein serves ≥ 80 %) and safety (adverse events). Secondary outcomes included macronutrient intake (3 × 24-h records), weight, moderate-to-vigorous physical activity (MVPA) and 30 s sit-to-stand (STS) performance. Study retention was 89 %. Mean exercise adherence (Pro-Ex) was 52 % with one adverse event from 241 sessions. In Pro-Ex, mean daily plant protein serves increased (0·9 to 1·4/d) and animal protein decreased (1·5 to 1·2/d) after 12-weeks, but overall adherence (serves/day) was 32[RD1] % (plant) and 42 % (animal). Relative to UC, Pro-Ex experienced a mean 2·7 (95 % CI: 0·9, 4·4) increase in 30 s STS number, 46-minute (95 % CI: -153, 245) increase in MVPA, 1·7 kg (95 % CI: -3·5, 0·2) decrease in weight, 35·2 g (95 % CI: 11·0, 59·3) increase in protein. In adults with NAFLD a telehealth home exercise and dietary intervention was safe and improved habitual plant and animal protein intake, but overall adherence was modest suggesting more intensive healthcare support may be required.

Mediterranean Diet and Mental Health in Children and Adolescents: A Systematic Review

CONTEXT

Childhood and adolescence are periods of critical importance in the development of mental health disorders. The Mediterranean diet (MD) has been linked to multiple positive health outcomes, including reduced incidence of mental health disorders and fewer psychiatric symptoms.

OBJECTIVE

This study aimed to investigate the association between adherence to an MD and mental health outcomes in children and adolescents.

METHODS

A systematic literature review was conducted of original research that explored the relationship between psychiatric symptoms or disorders and adherence to an MD. The literature search was conducted on PubMed, Scopus, Web of Science, MEDES, Dialnet, and Latindex from inception to November 2022, and the Newcastle-Ottawa Scale was used to evaluate the quality of studies.

RESULTS

A total of 13 studies (6 cross-sectional, 4 case-control, 2 randomized clinical trials, and 1 longitudinal cohort) out of 450 met the inclusion criteria. A total of 3058 children or adolescents with a mean age range from 8.6 to 16.2 years were included. Among the reviewed studies, 5 (71.42%) of those looking at attention-deficit/hyperactivity disorder, 4 (80%) examining depression, and 2 (50%) assessing anxiety found a significant protective association. Seven articles (53.84%) were found to be of high quality and 6 (46.15%) of moderate quality.

CONCLUSION

Adherence to an MD could be a protective factor for mental health in child and adolescent populations. This suggests that promoting an MD could help prevent the onset of clinical psychiatric symptoms, reduce symptom severity, and improve prognosis in young patients.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42021276316.

A Narrative Review of the Association Between Healthy Dietary Patterns and Depression

The purpose of the present review is the investigation of healthy dietary patterns and diet quality in relation to depression risk. Nutritional psychiatry is to develop scientifically based research that defines the role of nutrition and nutrients in various aspects of mental health. Growing evidence from the field suggests that diet may play an important role in the prevention and/or treatment of depression. In contrast, there is evidence that unhealthy diets may increase the risk of depression. This emerging research suggests that dietary interventions could help prevent depression or be an alternative or adjunctive therapy for depression. The Mediterranean diet (MedDiet), the Dietary Approaches to Stop Hypertension (DASH) diet, and the vegetarian diet are examined in this review. The electronic databases PubMed, Scopus, and Google Scholar were searched for relevant studies published during the last five years. We found many results that support that healthy eating patterns (high in vegetables, fruits, whole grains, nuts, seeds, and fish, low in processed foods) are related to a reduction in the risk of depression. The most robust findings are related to MedDiet, where we also found several positive results for the DASH diet. Regarding the vegetarian diet, there are inconsistent reports. Furthermore, a consistent finding refers to a lower Dietary Inflammatory Index (DII) as associated with a lower depression risk. It has been observed that people suffering from depression have poorer nutritional quality, with lower fruit and vegetable intake. This observation may strengthen the argument that nutritional interventions should be incorporated as an important "pillar" in the multifactorial treatment of patients. However, more well-designed studies are needed to establish the relationship between dietary patterns and mental health. In particular, interventional, longitudinal studies could be more enlightening.

Sex-specific effects of ketogenic diet on anxiety-like behavior and neuroimmune response in C57Bl/6J mice

The ketogenic diet (KD) has been shown to reduce anxiety and enhance cognitive functions in neurological diseases. However, the sex-specific effects of KD on anxiety-like behavior in healthy individuals and the underlying molecular mechanisms contributing to these effects, including neuroinflammation, are unelucidated. This study investigated the sex-specific effects of KD on anxiety-like behavior and the neuroimmune response in the prefrontal cortex (PFC) and hippocampus of healthy C57BL/6J male and female mice. Animals were fed either a control diet (CD- 17% fat, 65% carb, 18% protein) or a KD (80% fat, 5% carb, 15% protein) for 4 weeks. KD increased the levels of circulating β-hydroxybutyrate (BHB) both in males and females. However, PFC BHB levels were found to be elevated only in KD males. Moreover, KD did not affect the behavior of females but improved motor abilities and reduced anxiety levels in males. KD suppressed the mRNA expression of the pan microglial markers (Cd68, P2ry12) and induced morphological changes in the male PFC microglia. A sex-specific decrease in IL1β and an increase in IL-10 levels was found in the PFC of KD males. A similar trend was observed in the hippocampus of males where KD reduced the mRNA expression of P2ry12, Il1β, and cFos. Additionally, BHB increased the production of IL-10 whereas it decreased the production of IL1β from human microglia in in-vitro conditions. In summary, these results demonstrate that the anxiolytic and motor function enhancement abilities of KD are male-specific. Reduced pro-inflammatory and improved anti-inflammatory factors in the male PFC and hippocampus may underlie these effects.

Short-Chain Fatty Acids and Human Health: From Metabolic Pathways to Current Therapeutic Implications

The gastrointestinal tract is home to trillions of diverse microorganisms collectively known as the gut microbiota, which play a pivotal role in breaking down undigested foods, such as dietary fibers. Through the fermentation of these food components, short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are produced, offering numerous health benefits to the host. The production and absorption of these SCFAs occur through various mechanisms within the human intestine, contingent upon the types of dietary fibers reaching the gut and the specific microorganisms engaged in fermentation. Medical literature extensively documents the supplementation of SCFAs, particularly butyrate, in the treatment of gastrointestinal, metabolic, cardiovascular, and gut-brain-related disorders. This review seeks to provide an overview of the dynamics involved in the production and absorption of acetate, propionate, and butyrate within the human gut. Additionally, it will focus on the pivotal roles these SCFAs play in promoting gastrointestinal and metabolic health, as well as their current therapeutic implications.

Personalized Machine Learning-Based Prediction of Wellbeing and Empathy in Healthcare Professionals

Healthcare professionals are known to suffer from workplace stress and burnout, which can negatively affect their empathy for patients and quality of care. While existing research has identified factors associated with wellbeing and empathy in healthcare professionals, these efforts are typically focused on the group level, ignoring potentially important individual differences and implications for individualized intervention approaches. In the current study, we implemented N-of-1 personalized machine learning (PML) to predict wellbeing and empathy in healthcare professionals at the individual level, leveraging ecological momentary assessments (EMAs) and smartwatch wearable data. A total of 47 mood and lifestyle feature variables (relating to sleep, diet, exercise, and social connections) were collected daily for up to three months followed by applying eight supervised machine learning (ML) models in a PML pipeline to predict wellbeing and empathy separately. Predictive insight into the model architecture was obtained using Shapley statistics for each of the best-fit personalized models, ranking the importance of each feature for each participant. The best-fit model and top features varied across participants, with anxious mood (13/19) and depressed mood (10/19) being the top predictors in most models. Social connection was a top predictor for wellbeing in 9/12 participants but not for empathy models (1/7). Additionally, empathy and wellbeing were the top predictors of each other in 64% of cases. These findings highlight shared and individual features of wellbeing and empathy in healthcare professionals and suggest that a one-size-fits-all approach to addressing modifiable factors to improve wellbeing and empathy will likely be suboptimal. In the future, such personalized models may serve as actionable insights for healthcare professionals that lead to increased wellness and quality of patient care.

Bioactive Exploration in Functional Foods: Unlocking Nature's Treasures

BACKGROUND

Functional foods offer an appealing way to improve health and prevent chronic diseases, and this subject has received much attention lately. They are effective in preventing chronic diseases like cancer, diabetes, heart disease, and obesity, according to research.

OBJECTIVE

This work presents an in-depth analysis of functional foods, covering key challenges from a scientific, legal, and commercial perspective.

METHODS

Multiple databases were searched to find studies on functional foods included in the systematic literature review. Various aspects of functional foods, from their classification, impact on human wellness, effectiveness in inhibiting chronic diseases, the regulatory environment, global market trends, and industry challenges, are all clarified in this thorough review.

RESULTS

This study aims to enhance understanding and establish a pathway for functional foods to be acknowledged as valid choices in the field of dietary supplements. It provides a thorough investigation of bioactive compounds present in functional foods, including but not limited to polyphenols, carotenoids, omega fatty acids, prebiotics, probiotics, and dietary fiber, along with an overview of their potential to mitigate chronic illnesses. We engage in an in-depth exploration of regulatory frameworks, shed light on groundbreaking research advancements, and meticulously examine strategies for commercialization and the variety of global challenges that accompany them. Establishing scientific consensus, navigating complex regulatory processes, dealing with skeptical consumers, and rising levels of competition are all problems that need to be solved in this field.

CONCLUSION

The field of functional foods can advance further, promoting better public health outcomes, by deeply comprehending and addressing these complex dimensions.

Towards Personalised Mood Prediction and Explanation for Depression from Biophysical Data

Digital health applications using Artificial Intelligence (AI) are a promising opportunity to address the widening gap between available resources and mental health needs globally. Increasingly, passively acquired data from wearables are augmented with carefully selected active data from depressed individuals to develop Machine Learning (ML) models of depression based on mood scores. However, most ML models are black box in nature, and hence the outputs are not explainable. Depression is also multimodal, and the reasons for depression may vary significantly between individuals. Explainable and personalised models will thus be beneficial to clinicians to determine the main features that lead to a decline in the mood state of a depressed individual, thus enabling suitable personalised therapy. This is currently lacking. Therefore, this study presents a methodology for developing personalised and accurate Deep Learning (DL)-based predictive mood models for depression, along with novel methods for identifying the key facets that lead to the exacerbation of depressive symptoms. We illustrate our approach by using an existing multimodal dataset containing longitudinal Ecological Momentary Assessments of depression, lifestyle data from wearables and neurocognitive assessments for 14 mild to moderately depressed participants over one month. We develop classification- and regression-based DL models to predict participants' current mood scores-a discrete score given to a participant based on the severity of their depressive symptoms. The models are trained inside eight different evolutionary-algorithm-based optimisation schemes that optimise the model parameters for a maximum predictive performance. A five-fold cross-validation scheme is used to verify the DL model's predictive performance against 10 classical ML-based models, with a model error as low as 6% for some participants. We use the best model from the optimisation process to extract indicators, using SHAP, ALE and Anchors from explainable AI literature to explain why certain predictions are made and how they affect mood. These feature insights can assist health professionals in incorporating personalised interventions into a depressed individual's treatment regimen.

Exploring the Therapeutic Potential of Gamma-Aminobutyric Acid in Stress and Depressive Disorders through the Gut-Brain Axis

Research conducted on individuals with depression reveals that major depressive disorders (MDDs) coincide with diminished levels of the inhibitory neurotransmitter γ-aminobutyric acid (GABA) in the brain, as well as modifications in the subunit composition of the primary receptors (GABAA receptors) responsible for mediating GABAergic inhibition. Furthermore, there is substantial evidence supporting the significant role of GABA in regulating stress within the brain, which is a pivotal vulnerability factor in mood disorders. GABA is readily available and approved as a food supplement in many countries. Although there is substantial evidence indicating that orally ingested GABA may affect GABA receptors in peripheral tissues, there is comparatively less evidence supporting its direct action within the brain. Emerging evidence highlights that oral GABA intake may exert beneficial effects on the brain and psyche through the gut-brain axis. While GABA enjoys wide consumer acceptance in Eastern Asian markets, with many consumers reporting favorable effects on stress regulation, mood, and sleep, rigorous independent research is still largely lacking. Basic research, coupled with initial clinical findings, makes GABA an intriguing neuro-nutritional compound deserving of clinical studies in individuals with depression and other psychological problems.

Analysis of the Efficacy of Diet and Short-Term Probiotic Intervention on Depressive Symptoms in Patients after Bariatric Surgery: A Randomized Double-Blind Placebo Controlled Pilot Study

(1) Background: studies have shown that some patients experience mental deterioration after bariatric surgery. (2) Methods: We examined whether the use of probiotics and improved eating habits can improve the mental health of people who suffered from mood disorders after bariatric surgery. We also analyzed patients' mental states, eating habits and microbiota. (3) Results: Depressive symptoms were observed in 45% of 200 bariatric patients. After 5 weeks, we noted an improvement in patients' mental functioning (reduction in BDI and HRSD), but it was not related to the probiotic used. The consumption of vegetables and whole grain cereals increased (DQI-I adequacy), the consumption of simple sugars and SFA decreased (moderation DQI-I), and the consumption of monounsaturated fatty acids increased it. In the feces of patients after RYGB, there was a significantly higher abundance of two members of the Muribaculaceae family, namely Veillonella and Roseburia, while those after SG had more Christensenellaceae R-7 group, Subdoligranulum, Oscillibacter, and UCG-005. (4) Conclusions: the noted differences in the composition of the gut microbiota (RYGB vs. SG) may be one of the determinants of the proper functioning of the gut-brain microbiota axis, although there is currently a need for further research into this topic using a larger group of patients and different probiotic doses.

Dietary counselling plus omega-3 supplementation in the treatment of generalized anxiety disorder: protocol for a randomized wait-list controlled pilot trial (the "EASe-GAD Trial")

BACKGROUND

Anxiety disorders are prevalent and disabling conditions involving excessive worry and tension. Generalized anxiety disorder (GAD), the most common anxiety disorder, affects 5% of individuals from high-income countries and many individuals report that treatment options are not accessible, effective, or tolerable. Clinical evidence suggests that nutrition interventions, based on the Mediterranean diet and supplementation of omega-3 fatty acids, can significantly improve symptoms of depression; however, the effect of nutrition interventions on anxiety symptoms has not been studied in a clinical population. The primary objective of the present study is to assess the feasibility and acceptability of a dietary counselling and omega-3 fatty acid supplementation intervention delivered to adult women with GAD. The secondary objectives include assessing changes in anxiety symptom severity, assessing changes in quality of life, assessing changes in biomarkers, and evaluating the components of the program.

METHODS

This study is a randomized, wait-list controlled pilot trial delivering a 12-week, dietary counselling intervention and omega-3 supplementation to 50 adult women with GAD. Participants will complete seven individual counselling sessions which include education, personalized recommendations, mindful eating techniques, motivational interviewing, and goal setting. They will be provided with recipes, instructional videos, and food items. The intervention is designed based on the Social Cognitive Theory and previous research that has been done by the author team to identify dietary constituents with the most evidence to support their use in the treatment of anxiety disorders. Questionnaires and blood work will be completed at baseline, after the waiting period (for those in the waitlist group), and after the intervention.

DISCUSSION

Results from this study will lay the foundation for future large-scale studies in this area and may provide preliminary evidence of the role of diet counselling and omega-3 supplementation in the management of GAD. Research on the role of nutrition in psychiatric care has been identified as a priority by a number of international organizations. The present trial directly addresses the call for the research that is most needed to advance the field.

TRIAL REGISTRATION

This protocol was registered at ClinicalTrials.gov on October 10, 2022; NCT05573672 . Trial sponsor: The Canadian College of Naturopathic Medicine, 1255 Sheppard Ave E, Toronto, ON M2K 1E2, 416-498-1255. Steering committee: Composed of MA, LL, KC, IvdW, SM, UN, AJ. The committee meets monthly to oversee the trial. Protocol identifier: CCNM_EASe-GADCT_2201v4.

Ketogenic diet changes microglial morphology and the hippocampal lipidomic profile differently in stress susceptible versus resistant male mice upon repeated social defeat

Psychological stress confers an increased risk for several diseases including psychiatric conditions. The susceptibility to psychological stress is modulated by various factors, many of them being modifiable lifestyle choices. The ketogenic diet (KD) has emerged as a dietary regime that offers positive outcomes on mood and health status. Psychological stress and elevated inflammation are common features of neuropsychiatric disorders such as certain types of major depressive disorder. KD has been attributed anti-inflammatory properties that could underlie its beneficial consequences on the brain and behavior. Microglia are the main drivers of inflammation in the central nervous system. They are known to respond to both dietary changes and psychological stress, notably by modifying their production of cytokines and relationships among the brain parenchyma. To assess the interactions between KD and the stress response, including effects on microglia, we examined adult male mice on control diet (CD) versus KD that underwent 10 days of repeated social defeat (RSD) or remained non-stressed (controls; CTRLs). Through a social interaction test, stressed mice were classified as susceptible (SUS) or resistant (RES) to RSD. The mouse population fed a KD tended to have a higher proportion of individuals classified as RES following RSD. Microglial morphology and ultrastructure were then analyzed in the ventral hippocampus CA1, a brain region known to present structural alterations as a response to psychological stress. Distinct changes in microglial soma and arborization linked to the KD, SUS and RES phenotypes were revealed. Ultrastructural analysis by electron microscopy showed a clear reduction of cellular stress markers in microglia from KD fed animals. Furthermore, ultrastructural analysis showed that microglial contacts with synaptic elements were reduced in the SUS compared to the RES and CTRL groups. Hippocampal lipidomic analyses lastly identified a distinct lipid profile in SUS animals compared to CTRLs. These key differences, combined with the distinct microglial responses to diet and stress, indicate that unique metabolic changes may underlie the stress susceptibility phenotypes. Altogether, our results reveal novel mechanisms by which a KD might improve the resistance to psychological stress.

Nutritional counseling needs of patients with mental disorders in psychiatric care: A cross-sectional survey

BACKGROUND

The exploration of diet and nutrition as they relate to mental health and psychiatric disorders is a developing field. Anxiety, depression, and pharmacological treatments used to treat these disorders are likely to have side effects that induce decreases in activity and irregular eating habits, resulting in persistent nutritional imbalance. Unhealthy dietary patterns are associated with an increased risk of developing physical and mental health conditions. Despite this, nutritional support to patients in psychiatric care is not adequate.

AIMS

This study aimed to determine the factors underlying the need for nutritional counseling among patients with a mental disorder in psychiatry. The factors explored are eating-related symptoms, eating behavior, interest in food, seeking nutritional counseling, and impact on quality of life (QOL).

METHODS

We utilized a cross-sectional study design. Eligible patients were asked to complete a questionnaire regarding physical measurements and nutritional counseling. In addition, patients' diagnoses and blood test data were referenced from their medical records. The analysis focused on two groups: those who desired to consult a nutritionist and those who did not.

RESULTS

Ninety-three patients completed the study. The nutritional status and need for nutritional counseling in psychiatry patients indicates that patients with dietary problems requested nutritional counseling (p < .001). Patients who were more likely to need nutritional counseling had lower QOL in daily life (p = .011), pain/discomfort (p = .024), and anxiety/depression (p = .010) on the EuroQol 5-Dimension 5-level (EQ-5D-5L).

CONCLUSIONS

Patients with mental disorders who need nutritional counseling tend to have food-related problems and low QOL. It is necessary to establish an interdisciplinary system for nutritional counseling.

Ketogenic diet alters microglial morphology and changes the hippocampal lipidomic profile distinctively in stress susceptible versus resistant male mice upon repeated social defeat

Psychological stress confers an increased risk for several diseases including psychiatric conditions. The susceptibility to psychological stress is modulated by various factors, many of them being modifiable lifestyle choices. The ketogenic diet (KD) has emerged as a dietary regime that offers positive outcomes on mood and health status. Psychological stress and elevated inflammation are common features of neuropsychiatric disorders such as certain types of major depressive disorder. KD has been attributed anti-inflammatory properties that could underlie its beneficial consequences on the brain and behavior. Microglia are the main drivers of inflammation in the central nervous system. They are known to respond to both dietary changes and psychological stress, notably by modifying their production of cytokines and relationships among the brain parenchyma. To assess the interactions between KD and the stress response, including effects on microglia, we examined adult male mice on control diet (CD) versus KD that underwent 10 days of repeated social defeat (RSD) or remained non-stressed (controls; CTRLs). Through a social interaction test, stressed mice were classified as susceptible (SUS) or resistant (RES) to RSD. The mouse population fed a KD tended to have a higher proportion of individuals classified as RES following RSD. Microglial morphology and ultrastructure were then analyzed in the ventral hippocampus CA1, a brain region known to present structural alterations as a response to psychological stress. Distinct changes in microglial soma and arborization linked to the KD, SUS and RES phenotypes were revealed. Ultrastructural analysis by electron microscopy showed a clear reduction of cellular stress markers in microglia from KD fed animals. Furthermore, ultrastructural analysis showed that microglial contacts with synaptic elements were reduced in the SUS compared to the RES and CTRL groups. Hippocampal lipidomic analyses lastly identified a distinct lipid profile in SUS animals compared to CTRLs. These key differences, combined with the distinct microglial responses to diet and stress, indicate that unique metabolic changes may underlie the stress susceptibility phenotypes. Altogether, our results reveal novel mechanisms by which a KD might improve the resistance to psychological stress.

Short-chain fatty acids in diseases

Short-chain fatty acids (SCFAs) are the main metabolites produced by bacterial fermentation of dietary fibre in the gastrointestinal tract. The absorption of SCFAs is mediated by substrate transporters, such as monocarboxylate transporter 1 and sodium-coupled monocarboxylate transporter 1, which promote cellular metabolism. An increasing number of studies have implicated metabolites produced by microorganisms as crucial executors of diet-based microbial influence on the host. SCFAs are important fuels for intestinal epithelial cells (IECs) and represent a major carbon flux from the diet, that is decomposed by the gut microbiota. SCFAs play a vital role in multiple molecular biological processes, such as promoting the secretion of glucagon-like peptide-1 by IECs to inhibit the elevation of blood glucose, increasing the expression of G protein-coupled receptors such as GPR41 and GPR43, and inhibiting histone deacetylases, which participate in the regulation of the proliferation, differentiation, and function of IECs. SCFAs affect intestinal motility, barrier function, and host metabolism. Furthermore, SCFAs play important regulatory roles in local, intermediate, and peripheral metabolisms. Acetate, propionate, and butyrate are the major SCFAs, they are involved in the regulation of immunity, apoptosis, inflammation, and lipid metabolism. Herein, we review the diverse functional roles of this major class of bacterial metabolites and reflect on their ability to affect intestine, metabolic, and other diseases. Video Abstract.

Clinical guidelines for the use of lifestyle-based mental health care in major depressive disorder: World Federation of Societies for Biological Psychiatry (WFSBP) and Australasian Society of Lifestyle Medicine (ASLM) taskforce

OBJECTIVES

The primary objectives of these international guidelines were to provide a global audience of clinicians with (a) a series of evidence-based recommendations for the provision of lifestyle-based mental health care in clinical practice for adults with Major Depressive Disorder (MDD) and (b) a series of implementation considerations that may be applicable across a range of settings.

METHODS

Recommendations and associated evidence-based gradings were based on a series of systematic literature searches of published research as well as the clinical expertise of taskforce members. The focus of the guidelines was eight lifestyle domains: physical activity and exercise, smoking cessation, work-directed interventions, mindfulness-based and stress management therapies, diet, sleep, loneliness and social support, and green space interaction. The following electronic bibliographic databases were searched for articles published prior to June 2020: PubMed, EMBASE, The Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Methodology Register), CINAHL, PsycINFO. Evidence grading was based on the level of evidence specific to MDD and risk of bias, in accordance with the World Federation of Societies for Biological Psychiatry criteria.

RESULTS

Nine recommendations were formed. The recommendations with the highest ratings to improve MDD were the use of physical activity and exercise, relaxation techniques, work-directed interventions, sleep, and mindfulness-based therapies (Grade 2). Interventions related to diet and green space were recommended, but with a lower strength of evidence (Grade 3). Recommendations regarding smoking cessation and loneliness and social support were based on expert opinion. Key implementation considerations included the need for input from allied health professionals and support networks to implement this type of approach, the importance of partnering such recommendations with behaviour change support, and the need to deliver interventions using a biopsychosocial-cultural framework.

CONCLUSIONS

Lifestyle-based interventions are recommended as a foundational component of mental health care in clinical practice for adults with Major Depressive Disorder, where other evidence-based therapies can be added or used in combination. The findings and recommendations of these guidelines support the need for further research to address existing gaps in efficacy and implementation research, especially for emerging lifestyle-based approaches (e.g. green space, loneliness and social support interventions) where data are limited. Further work is also needed to develop innovative approaches for delivery and models of care, and to support the training of health professionals regarding lifestyle-based mental health care.

Microbiome and immuno-metabolic dysregulation in patients with major depressive disorder with atypical clinical presentation

Depression is highly prevalent (6% 1-year prevalence) and is the second leading cause of disability worldwide. Available treatment options for depression are far from optimal, with response rates only around 50%. This is most likely related to a heterogeneous clinical presentation of major depression disorder (MDD), suggesting different manifestations of underlying pathophysiological mechanisms. Poorer treatment outcomes to first-line antidepressants were reported in MDD patients endorsing an "atypical" symptom profile that is characterized by preserved reactivity in mood, increased appetite, hypersomnia, a heavy sensation in the limbs, and interpersonal rejection sensitivity. In recent years, evidence has emerged that immunometabolic biological dysregulation is an important underlying pathophysiological mechanism in depression, which maps more consistently to atypical features. In the last few years human microbial residents have emerged as a key influencing variable associated with immunometabolic dysregulations in depression. The microbiome plays a critical role in the training and development of key components of the host's innate and adaptive immune systems, while the immune system orchestrates the maintenance of key features of the host-microbe symbiosis. Moreover, by being a metabolically active ecosystem commensal microbes may have a huge impact on signaling pathways, involved in underlying mechanisms leading to atypical depressive symptoms. In this review, we discuss the interplay between the microbiome and immunometabolic imbalance in the context of atypical depressive symptoms. Although research in this field is in its infancy, targeting biological determinants in more homogeneous clinical presentations of MDD may offer new avenues for the development of novel therapeutic strategies for treatment-resistant depression.

Feed your microbes to deal with stress: a psychobiotic diet impacts microbial stability and perceived stress in a healthy adult population

The impact of diet on the microbiota composition and the role of diet in supporting optimal mental health have received much attention in the last decade. However, whether whole dietary approaches can exert psychobiotic effects is largely understudied. Thus, we investigated the influence of a psychobiotic diet (high in prebiotic and fermented foods) on the microbial profile and function as well as on mental health outcomes in a healthy human population. Forty-five adults were randomized into either a psychobiotic (n = 24) or control (n = 21) diet for 4 weeks. Fecal microbiota composition and function was characterized using shotgun sequencing. Stress, overall health and diet were assessed using validated questionnaires. Metabolic profiling of plasma, urine and fecal samples was performed. Intervention with a psychobiotic diet resulted in reductions of perceived stress (32% in diet vs. 17% in control group), but not between groups. Similarly, biological marker of stress were not affected. Additionally, higher adherence to the diet resulted in stronger decreases in perceived stress. While the dietary intervention elicited only subtle changes in microbial composition and function, significant changes in the level of 40 specific fecal lipids and urinary tryptophan metabolites were observed. Lastly, microbial volatility was linked to greater changes in perceived stress scores in those on the psychobiotic diet. These results highlight that dietary approaches can be used to reduce perceived stress in a human cohort. Using microbiota-targeted diets to positively modulate gut-brain communication holds possibilities for the reduction of stress and stress-associated disorders, but additional research is warranted to investigate underlying mechanisms, including the role of the microbiota.

Heterogeneity in major depressive disorder: The need for biomarker-based personalized treatments

Major Depressive Disorder (MDD) or depression is a pathological mental condition affecting millions of people worldwide. Identification of objective biological markers of depression can provide for a better diagnostic and intervention criteria; ultimately aiding to reduce its socioeconomic health burden. This review provides a comprehensive insight into the major biomarker candidates that have been implicated in depression neurobiology. The key biomarker categories are covered across all the "omics" levels. At the epigenomic level, DNA-methylation, non-coding RNA and histone-modifications have been discussed in relation to depression. The proteomics system shows great promise with inflammatory markers as well as growth factors and neurobiological alterations within the endocannabinoid system. Characteristic lipids implicated in depression together with the endocrine system are reviewed under the metabolomics section. The chapter also examines the novel biomarkers for depression that have been proposed by studies in the microbiome. Depression affects individuals differentially and explicit biomarkers identified by robust research criteria may pave the way for better diagnosis, intervention, treatment, and prediction of treatment response.

A Mediterranean and Low-Fat dietary intervention in Non-Alcoholic Fatty Liver Disease patients -Exploring participant experience and perceptions about dietary change

BACKGROUND

A Mediterranean Diet (MD) appears to be beneficial in NAFLD patients in Mediterranean countries, however the acceptability of a MD in non-Mediterranean populations has not been thoroughly explored. This study aimed to explore the acceptability, through understanding the barriers and enablers of MD and low-fat diet (LFD) interventions as perceived by Australian adults from multicultural backgrounds, with NAFLD, who participated.

METHODOLOGY

Semi-structured telephone interviews were performed with 23 NAFLD trial participants at the end of a 12-week dietary intervention in a multicentre, parallel, randomised clinical trial. Data was analysed using thematic analysis.

RESULTS

Participants reported that they enjoyed taking part in the MD and LFD interventions and perceived that they had positive health benefits from their participation. Compared to the LFD, the MD group placed greater emphasis on enjoyment and intention to maintain dietary changes. Novelty, convenience and the ability to swap food/meals were key enablers for the successful implementation for both of the dietary interventions. Flavour and enjoyment of food, expressed more prominently by MD intervention participants, were fundamental components of the diets with regard to reported adherence and intention to maintain dietary change.

CONCLUSIONS

Participants randomised to the MD reported greater acceptability of the diet than those randomised to the LFD, predominantly related to perceived novelty and palatability of the diet. This article is protected by copyright. All rights reserved.

Long-Term Adherence to a Mediterranean Diet 1-Year after Completion of the MedLey Study

Mediterranean populations enjoy the health benefits of a Mediterranean diet (MedDiet), but is it feasible to implement such a pattern beyond the Mediterranean region? The MedLey trial, a 6-month MedDiet intervention vs habitual diet in older Australians, demonstrated that the participants could maintain high adherence to a MedDiet for 6 months. The MedDiet resulted in improved systolic blood pressure (BP), endothelial dilatation, oxidative stress, and plasma triglycerides in comparison with the habitual diet. We sought to determine if 12 months after finishing the MedLey study, the participants maintained their adherence to the MedDiet principles and whether the reduction in the cardiovascular disease (CVD) risk factors that were seen in the trial were sustained. Participants completed a food frequency questionnaire, and a 15-point MedDiet adherence score (MDAS; greater score = greater adherence) was calculated. Home BP was measured over 6 days, BMI was assessed, and fasting plasma triglycerides were measured. The data were analysed using intention-to-treat linear mixed effects models with a group × time interaction term, comparing data at baseline, 2, 4, and 18 months (12 months post-trial). At 18 months (12 months after finishing the MedLey study), the MedDiet group had a MDAS of 7.9 ± 0.3, compared to 9.6 ± 0.2 at 4 months (p < 0.0001), and 6.7 ± 0.2 (p < 0.0001), at baseline. The MDAS in the HabDiet group remained unchanged over the 18-month period (18 months 6.9 ± 0.3, 4 months 6.9 ± 0.2, baseline 6.7 ± 0.2). In the MedDiet group, the consumption of olive oil, legumes, fish, and vegetables remained higher (p < 0.01, compared with baseline) and discretionary food consumption remained lower (p = 0.02) at 18 months. These data show that some MedDiet principles could be adhered to for 12 months after finishing the MedLey trial. However, improvements in cardiometabolic health markers, including BP and plasma triglycerides, were not sustained. The results indicate that further dietary support for behaviour change may be beneficial to maintaining high adherence and metabolic benefits of the MedDiet.

Biological Role of Nutrients, Food and Dietary Patterns in the Prevention and Clinical Management of Major Depressive Disorder

Major Depressive Disorder (MDD) is a growing disabling condition affecting around 280 million people worldwide. This complex entity is the result of the interplay between biological, psychological, and sociocultural factors, and compelling evidence suggests that MDD can be considered a disease that occurs as a consequence of an evolutionary mismatch and unhealthy lifestyle habits. In this context, diet is one of the core pillars of health, influencing multiple biological processes in the brain and the entire body. It seems that there is a bidirectional relationship between MDD and malnutrition, and depressed individuals often lack certain critical nutrients along with an aberrant dietary pattern. Thus, dietary interventions are one of the most promising tools to explore in the field of MDD, as there are a specific group of nutrients (i.e., omega 3, vitamins, polyphenols, and caffeine), foods (fish, nuts, seeds fruits, vegetables, coffee/tea, and fermented products) or dietary supplements (such as S-adenosylmethionine, acetyl carnitine, creatine, amino acids, etc.), which are being currently studied. Likewise, the entire nutritional context and the dietary pattern seem to be another potential area of study, and some strategies such as the Mediterranean diet have demonstrated some relevant benefits in patients with MDD; although, further efforts are still needed. In the present work, we will explore the state-of-the-art diet in the prevention and clinical support of MDD, focusing on the biological properties of its main nutrients, foods, and dietary patterns and their possible implications for these patients.

'Effectiveness of a remote nutritional intervention to increase the adherence to the Mediterranean diet among recovered depression patients'

BACKGROUND

There is substantial evidence supporting that remote interventions are useful to change dietary habits. However, the effect of a remote intervention based on Mediterranean diet (MD) in depressive patients has been less explored.

OBJECTIVE

This study aims to assess the effectiveness of a remotely provided Mediterranean diet-based nutritional intervention in the context of a secondary prevention trial of depression.

METHODS

The PREDIDEP study was a 2-year multicenter, randomized, single-blinded trial designed to assess the effect of the MD enriched with extra virgin olive oil (EVOO) on the prevention of depression recurrence. The intervention group received usual care for depressed patients and remote nutritional intervention every three months which included phone contacts and web-based interventions; and the control group, usual care. At baseline and at 1-year and 2-year follow-up, the 14-item MD Adherence Screener (MEDAS) questionnaire and a semiquantitative food frequency questionnaire (FFQ) were collected by a dietitian. Mixed effects linear models were used to assess changes in nutritional variables according to the group of intervention. The trial was registered at ClinicalTrials.gov NCT03081065.

RESULTS

Compared with control group, the MD intervention group showed more adherence to MD (between-group difference: 2.76; 95% CI 2.13-3.39; p < 0.001); and a healthier diet pattern with a significant increase in the consumption of olive oil (p < 0.001), and a significant reduction in refined cereals (p = 0.031) after 2 years of intervention.

CONCLUSIONS

The remote nutritional intervention increases adherence to the MD among recovered depression patients.Trial registration: ClinicalTrials.gov identifier: NCT03081065.

Application of Mediterranean Diet in Cardiovascular Diseases and Type 2 Diabetes Mellitus: Motivations and Challenges

Objective: Cardiovascular disease (CVD) is the leading cause of disability and death in many countries. Together with CVD, Type 2 diabetes mellitus (T2DM) accounts for more than 80% of all premature non-communicable disease deaths. The protective effect of the Mediterranean diet (MedDiet) on CVD and its risk factors, including T2DM, has been a constant topic of interest. Notwithstanding, despite the large body of evidence, scientists are concerned about the challenges and difficulties of the application of MedDiet. This review aims to explore the motivations and challenges for using MedDiet in patients with CVD and T2DM. Design: An electronic search was conducted for articles about MedDiet published in PubMed, ScienceDirect, Scopus, and Web of Science up to December 2021, particularly on CVD and T2DM patients. From a total of 1536 studies, the final eligible set of 108 studies was selected. Study selection involved three iterations of filtering. Results: Motivation to apply MedDiet was driven by the importance of studying the entire food pattern rather than just one nutrient, the health benefits, and the distinct characteristics of MedDiet. Challenges of the application of MedDiet include lacking universal definition and scoring of MedDiet. Influences of nutritional transition that promote shifting of traditional diets to Westernized diets further complicate the adherence of MedDiet. The challenges also cover the research aspects, including ambiguous and inconsistent findings, the inexistence of positive results, limited evidence, and generalization in previous studies. The review revealed that most of the studies recommended that future studies are needed in terms of health benefits, describing the potential benefits of MedDiet, identifying the barriers, and mainly discussing the effect of MedDiet in different populations. Conclusions: In general, there is consistent and strong evidence that MedDiet is associated inversely with CVD risk factors and directly with glycemic control. MedDiet is the subject of active and diverse research despite the existing challenges. This review informs the health benefits conferred by this centuries-old dietary pattern and highlights MedDiet could possibly be revolutionary, practical, and non-invasive approach for the prevention and treatment CVD and T2DM.

Evaluating telehealth lifestyle therapy versus telehealth psychotherapy for reducing depression in adults with COVID-19 related distress: the curbing anxiety and depression using lifestyle medicine (CALM) randomised non-inferiority trial protocol

BACKGROUND

There is increasing recognition of the substantial burden of mental health disorders at an individual and population level, including consequent demand on mental health services. Lifestyle-based mental healthcare offers an additional approach to existing services with potential to help alleviate system burden. Despite the latest Royal Australian New Zealand College of Psychiatrists guidelines recommending that lifestyle is a 'first-line', 'non-negotiable' treatment for mood disorders, few such programs exist within clinical practice. Additionally, there are limited data to determine whether lifestyle approaches are equivalent to established treatments. Using an individually randomised group treatment design, we aim to address this gap by evaluating an integrated lifestyle program (CALM) compared to an established therapy (psychotherapy), both delivered via telehealth. It is hypothesised that the CALM program will not be inferior to psychotherapy with respect to depressive symptoms at 8 weeks.

METHODS

The study is being conducted in partnership with Barwon Health's Mental Health, Drugs & Alcohol Service (Geelong, Victoria), from which 184 participants from its service and surrounding regions are being recruited. Eligible participants with elevated psychological distress are being randomised to CALM or psychotherapy. Each takes a trans-diagnostic approach, and comprises four weekly (weeks 1-4) and two fortnightly (weeks 6 and 8) 90-min, group-based sessions delivered via Zoom (digital video conferencing platform). CALM focuses on enhancing knowledge, behavioural skills and support for improving dietary and physical activity behaviours, delivered by an Accredited Exercise Physiologist and Accredited Practising Dietitian. Psychotherapy uses cognitive behavioural therapy (CBT) delivered by a Psychologist or Clinical Psychologist, and Provisional Psychologist. Data collection occurs at baseline and 8 weeks. The primary outcome is depressive symptoms (assessed via the Patient Health Questionnaire-9) at 8 weeks. Societal and healthcare costs will be estimated to determine the cost-effectiveness of the CALM program. A process evaluation will determine its reach, adoption, implementation and maintenance.

DISCUSSION

If the CALM program is non-inferior to psychotherapy, this study will provide the first evidence to support lifestyle-based mental healthcare as an additional care model to support individuals experiencing psychological distress.

TRIAL REGISTRATION

Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12621000387820 , Registered 8 April 2021.

[Practical aspects of ketamine treatment-Safety, combination treatment and comorbidities]

BACKGROUND

Although multiple studies and meta-analyses have documented the rapid antidepressive efficacy of ketamine, there are numerous questions regarding the practical use in the clinical routine that are still unanswered.

OBJECTIVE

Based on personal clinical experience, by comparison and supplementation of the current data situation, answers are given to questions regarding the practical use of ketamine for depression that have not yet been satisfactorily clarified.

MATERIAL AND METHODS

The clinical experiences with antidepressive treatment using ketamine over more than 5 years were evaluated with respect to the questions at hand. This was followed by a qualitative comparison of these results with those of a narrative literature search.

RESULTS

A total of 72 patients (unipolar depression n = 53, bipolar depression n = 16, schizoaffective depression n = 3) were included in the analysis of this cohort. A statistically significant reduction of depressive symptoms and suicidal ideation after S-ketamine treatment was found. Of the patients 61% suffered from at least one secondary diagnosis. A dose of 0.5 mg/kg body weight of S‑ketamine at a frequency of three times per week was shown to be effective. The treatment appears to be safe with respect to urotoxic side effects, combination treatment with tranylcypromine and in comorbid posttraumatic stress disorder.

CONCLUSION

Ketamine appears to be a safe and effective option for the treatment of unipolar and bipolar depression.

Daily Vinegar Ingestion Improves Depression Scores and Alters the Metabolome in Healthy Adults: A Randomized Controlled Trial

Daily vinegar ingestion has been linked to improved glycemic control, but recent data suggest a separate unexplored role for vinegar in mental health. Utilizing a placebo-controlled, parallel arm study design, this 4-week trial examined the impact of daily vinegar ingestion on mood states and urinary metabolites in healthy college students. Participants were randomized to the vinegar group (VIN: n = 14; 1.5 g acetic acid/day as liquid vinegar) or the control group (CON: n = 11; 0.015 g acetic acid/day as a pill) with no change to customary diet or physical activity. At baseline and at study week four, participants completed the Profile of Mood States (POMS) and the Center for Epidemiological Studies-Depression (CES-D) questionnaires and provided a first-morning urine sample for targeted metabolomics analyses. The change in both POMS depression scores and CES-D scores differed significantly between groups favoring improved affect in the VIN versus CON participants after four weeks. Metabolomics analyses pre and post-intervention suggested metabolite alterations associated with vinegar ingestion that are consistent for improved mood, including enzymatic dysfunction in the hexosamine pathway as well as significant increases in glycine, serine, and threonine metabolism. These data warrant continued investigation of vinegar as a possible agent to improve mood state.

Neuroprotective effects of oleuropein: Recent developments and contemporary research

Neurological disorders are increasing at a faster pace due to oxidative stress, protein aggregation, excitotoxicity, and neuroinflammation. It is reported that the Mediterranean diet including olives as a major dietary component prevents and ameliorates neurological anomalies. Oleuropein is the major bioactive component in different parts of the Olive (Olea europaea L.) tree. Several mechanisms have been reported for the neuroprotective role of oleuropein including induction of apoptosis and autophagy, enhancing the antioxidant pool of the cerebral region, decreasing the unnecessary release of proinflammatory cytokines and chemokines by deactivating the microglia cells and astrocytes thus preventing the occurrence of neuroinflammation. Regular intake of oleuropein seems to be correlated with decreased risks of neural disorders including Alzheimer's, Parkinson's, strokes, depression, anxiety, epilepsy, and others. This review majorly discusses the chemistry, biosynthesis, and metabolism of oleuropein along with an updated vision of its neuroprotective role in counteracting the acute and chronic neurodegenerative and neuropsychiatric disorders. Moreover, mechanisms by which oleuropein may prevent neurodegeneration are reviewed. PRACTICAL APPLICATION: Neurological disorders are negatively affecting the health and life quality of individuals around the globe. Although various medicinal solutions are available to tackle such ailments, none has proven to fully cure and being deprived of side effects. In this respect, the prevention of such disorders using natural remedies may be an effective strategy to overcome the incidence of the increasing cases. Furthermore, the natural compounds provide a safer alternative to pharmaceutical drugs. Hence, oleuropein from olive tree products is found to be efficacious against neurological disorders. This review provides an updated insight on the positive effects of oleuropein against neurodegenerative and neuropsychiatric disorders. The diet practitioners and nutraceutical companies may benefit from the provided information to design and develop strategies to improve the mental health of suffering individuals.

Designing Lifestyle Interventions for Common Mental Disorders: What Can We Learn from Diabetes Prevention Programs?

Lifestyle factors including diet, sleep, physical activity, and substance use cessation, are recognised as treatment targets for common mental disorders (CMDs). As the field of lifestyle-based mental health care evolves towards effectiveness trials and real-world translation, it is timely to consider how such innovations can be integrated into clinical practice. This paper discusses the utility and scale-up of lifestyle interventions for CMDs and draws on diabetes prevention literature to identify enablers and barriers to translation efforts. We discuss the extent to which lifestyle interventions aimed at managing CMDs and preventing diabetes share commonalities (program content, theoretical underpinnings, program structures, interventionists, frameworks promoting fidelity, quality, sustainability). Specific considerations when utilising these programs for mental health include personalising content with respect to symptoms and trajectories of depression and anxiety, medication regimen and genetic risk profile. As this field moves from efficacy to effectiveness and implementation, it is important to ensure issues in implementation science, including "voltage drop", "program drift", logistics, funding, and resourcing, are in line with evidence-based models that are effective in research settings. Ongoing considerations includes who is best placed to deliver this care and the need for models to support implementation including long-term financing, workforce training, supervision, stakeholder and organisational support.

The impact of maternal post-partum depressive symptoms on child diet at 18 months

Post-partum depression (PPD) is a serious mental health problem, which can impair maternal behaviours and adversely affect the cognitive, emotional and behavioural development of children. This study aims to explore the impact of maternal depressive symptoms at 3 months post-partum (baseline) on child diet at 18 months of age (follow-up). This study used longitudinal data from 263 first-time mothers from the Melbourne Infant Feeding, Activity and Nutrition Trial (InFANT) Extend. Women self-reported depressive symptoms (10-item Center for Epidemiological Studies Depression Scale [CES-D]) and child diet (fruits, vegetables and discretionary foods). Multiple linear regression analyses were used to explore the relationship between maternal depressive symptoms at baseline and child fruit and vegetable intake and discretionary food intake (g day-1 ) at follow-up. Baseline maternal depressive symptoms were associated with higher childhood consumption of discretionary foods at 18 months of age (β = 0.45, 95% confidence interval [CI] 0.03 to 0.87, P = 0.034 [adjusted]). There was no evidence of association for maternal depressive symptoms and child intake of fruits and vegetables. Further longitudinal studies are warranted to confirm these findings, with the hope of translating this knowledge into optimal clinic care and improved physical and mental health for mother and child.

Carbohydrate-to-Fiber Ratio, a Marker of Dietary Intake, as an Indicator of Depressive Symptoms

OBJECTIVE

The aim of this study is to evaluate the association between a marker of dietary intake, the carbohydrate-to-fiber (CF) ratio, and moderate-to-severe depressive symptoms.

DESIGN

Cross-sectional study.

SETTING

National Health and Nutrition Examination Survey (NHANES) database from 2013-2016.

PARTICIPANTS

Individuals 18 years and older were included. Participants with total energy intake outside of three standard deviations of the mean, pregnant or breastfeeding women, and those with missing data were excluded.

MEASUREMENTS

The main independent variable, CF ratio, was generated using corresponding variables in NHANES and divided into quartiles. The main outcome was depressive symptoms using the Patient Health Questionnaire-9. Unadjusted and adjusted logistic regression analyses were used to calculate odds ratios and their corresponding 95% confidence interval (CI).  Results: Among all participants (n=9,728), 8.3% reported to have moderate-to-severe depressive symptoms (n=833). The highest proportion of depressive symptoms was reported in respondents in quartile 4 (Q4), with the highest CF ratio (13.0%; p<0.001). After adjustment, the odds of depressive symptoms significantly increased in Q4 of the CF ratio compared with Q1 (adjusted odds ratio 1.4, 95% CI 1.0-1.9). The prevalence of depressive symptoms significantly increased in females, lower federal poverty levels, non-married individuals, smokers, and hypertension patients.  Conclusion: This nationally representative sample suggests that a higher CF dietary intake ratio increases the risk of moderate-to-severe depressive symptoms. These results suggest that the CF ratio may help clinicians and patients evaluate their dietary risk for depressive symptoms. Further prospective studies are needed to validate this ratio as a dietary measurement.

Ketogenic diet for depression: A potential dietary regimen to maintain euthymia?

Approximately 30% of patients with major depressive disorder (MDD) present resistance to current pharmacological therapies. There is the possibility that an appropriate nutritional regimen can maintain euthymia. Poor dietary pattern and lack of nutritional knowledge are common among today's population; nutrient-rich foods are being replaced by highly processed foods that lead to a higher risk of developing chronic diseases such as metabolic syndrome, hypercholesterolemia, and diabetes. There is growing evidence of the beneficial role of vitamins and dietary supplements for improving symptoms in a range of affective disorders by regulating the gut microbiome, gut-brain axis, and neurotransmitter levels. Reduced GABA neurotransmission is regularly observed in MDD. Moreover, positive allosteric GABA modulators (i.e benzodiazepines) are widely prescribed to alleviate depression symptoms, but their use needs to be limited, as it can lead to addiction. An alternative option may be the adherence to a ketogenic diet, which consists of low-carbohydrate, moderate-protein, and high-fat intake. It is mainly known for its beneficial role in weight-loss, refractory epilepsy treatment, and balancing glucose levels. A ketogenic diet can also increase GABA levels to aid the mechanism of action of monoaminergic drugs. Thus, it could potentially be used in the treatment for affective disorders due to its potential role in GABA/glutamate balance. While more research is needed before this regimen can be regularly recommended to patients, here we discuss evidence that may encourage physicians to prescribe ketogenic diet as an adjuvant for patients receiving psychotherapy and pharmacology.

Introducing Plant-Based Mediterranean Diet as a Lifestyle Medicine Approach in Latin America: Opportunities Within the Chilean Context

Latin America is experiencing a significant epidemiological and nutritional transition, with a trend toward higher incidence of food-related chronic diseases. In this context, Lifestyle Medicine (LM) is a growing field focused on assisting individuals in adopting healthy behaviors for the prevention and treatment of these chronic diseases, including, among other pillars, a great emphasis on healthy eating. There is also a growing interest worldwide in environmental sustainability of dietary patterns, with increasing concern about their effects on planetary health. In this context, whole-food, plant-based diets -such as the Mediterranean diet (MD)- have emerged as a solution for both healthier eating and lowering environmental impact. Yet in order to be effective at these goals and achieve a high adherence to any nutritional prescription, the sociocultural reality of the community or population where we aim to practice must also be taken into account. In this review, we specifically highlight the plant-based MD as a LM-contextualized dietary pattern that is adaptable, applicable, and sustainable within the Chilean context and has the potential to address the current trend of chronic diseases in our country.

Personalized machine learning of depressed mood using wearables

Depression is a multifaceted illness with large interindividual variability in clinical response to treatment. In the era of digital medicine and precision therapeutics, new personalized treatment approaches are warranted for depression. Here, we use a combination of longitudinal ecological momentary assessments of depression, neurocognitive sampling synchronized with electroencephalography, and lifestyle data from wearables to generate individualized predictions of depressed mood over a 1-month time period. This study, thus, develops a systematic pipeline for N-of-1 personalized modeling of depression using multiple modalities of data. In the models, we integrate seven types of supervised machine learning (ML) approaches for each individual, including ensemble learning and regression-based methods. All models were verified using fourfold nested cross-validation. The best-fit as benchmarked by the lowest mean absolute percentage error, was obtained by a different type of ML model for each individual, demonstrating that there is no one-size-fits-all strategy. The voting regressor, which is a composite strategy across ML models, was best performing on-average across subjects. However, the individually selected best-fit models still showed significantly less error than the voting regressor performance across subjects. For each individual's best-fit personalized model, we further extracted top-feature predictors using Shapley statistics. Shapley values revealed distinct feature determinants of depression over time for each person ranging from co-morbid anxiety, to physical exercise, diet, momentary stress and breathing performance, sleep times, and neurocognition. In future, these personalized features can serve as targets for a personalized ML-guided, multimodal treatment strategy for depression.

Gutted! Unraveling the Role of the Microbiome in Major Depressive Disorder

Microorganisms can be found in virtually any environment. In humans, the largest collection of microorganisms is found in the gut ecosystem. The adult gut microbiome consists of more genes than its human host and typically spans more than 60 genera from across the taxonomic tree. In addition, the gut contains the largest number of neurons in the body, after the brain. In recent years, it has become clear that the gut microbiome is in communication with the brain, through the gut-brain axis. A growing body of literature shows that the gut microbiome plays a shaping role in a variety of psychiatric disorders, including major depressive disorder (MDD). In this review, the interplay between the microbiome and MDD is discussed in three facets. First, we discuss factors that affect the onset/development of MDD that also greatly impinge on the composition of the gut microbiota-especially diet and stressful life events. We then examine the interplay between the microbiota and MDD. We examine evidence suggesting that the microbiota is altered in MDD, and we discuss why the microbiota should be considered during MDD treatment. Finally, we look toward the future and examine how the microbiota might become a therapeutic target for MDD. This review is intended to introduce those familiar with the neurological and psychiatric aspects of MDD to the microbiome and its potential role in the disorder. Although research is in its very early days, with much yet to be the understood, the microbiome is offering new avenues for developing potentially novel strategies for managing MDD.

Assessing the feasibility of an m-Health intervention for changing diet quality and mood in individuals with depression: the My Food & Mood program

Recent randomized controlled trials have shown that improving diet quality reduces symptoms in those with depression. The provision of digital health interventions that can support dietary change in those with depression has important benefits with respect to reach, accessibility convenience and cost. The My Food & Mood study used single arm cohort design to test the feasibility of such an intervention. Participants with current depressive symptoms were recruited and enrolled online to use the My Food & Mood m-Health (smartphone delivered) program for 8 weeks. Participants completed depression (PHQ-8) and dietary questionnaires (MEDAS) at baseline, week 4 and week 8. Metrics of use and intensity of use engagement measures were calculated from system logs and data entries. There was a significant change in both MEDAS score (t = 8.147, df = 44, p < 0.001) and PHQ-8 score (t = -7.199, df = 44, p < 0.001) throughout the study. There was a moderate positive association between change in MEDAS score and activities completed, goals and weeks engaged, and a strong inverse association between change in MEDAS score and change in PHQ-8 score. An m-Health program targeting dietary intervention in those with depression was feasible. Dietary change was associated with higher engagement and reduced depressive symptoms.

Optimizing Engagement in an Online Dietary Intervention for Depression (My Food & Mood Version 3.0): Cohort Study

BACKGROUND

Online interventions can be a cost-effective and efficient way to deliver programs to large numbers of people regardless of geographic location. However, attrition in web-based interventions is often an issue. Developing ways to keep participants engaged is important for ensuring validity and limiting potential biases. We developed a web-based dietary intervention as part of The My Food & Mood study which aimed to optimize ways to engage participants with low mood or depressive symptoms to promote dietary behavior change. Different versions of the My Food & Mood program were tested during optimization. Iterations were developed based on user feedback and usage analysis.

OBJECTIVE

The purpose of this study was to compare engagement and nonusage attrition across 4 program iterations-which differed by platform format, delivery mode, and activity type-to create an optimized version.

METHODS

Each program version contained modular videos with key activities with respect to implementing behavior change techniques of equivalent levels of required participation and length: version 1.0, desktop program and smartphone app; version 2.1, desktop or smartphone program; version 2.2, desktop program; and version 3.0, smartphone app. Adults with PHQ-8 scores of 5 or greater were recruited online and assigned to 1 of the 4 versions. Participants were asked to use the program for 8 weeks and complete measures at weeks 4 and 8. Engagement data were collected from the web-based platform system logs and customized reports. Cox regression survival analysis examined nonusage attrition and Kruskal-Wallis tests compared engagement across each cohort.

RESULTS

A total of 614 adults participated. Kruskal-Wallis tests showed significant differences across the 4 cohorts in all engagement measures. The smartphone app (version 3.0) had the greatest engagement as measured by weeks engaged, total usage time, total time key activities, number of active sessions, percentage of activities completed against protocol, goals completed, and percentage of videos watched. Cox regression multivariate survival analysis showed referral from a health practitioner (hazard ratio [HR] 0.344, P=.001) and greater proficiency with computers (HR 0.796, P=.049) reduced the risk of nonusage attrition. Computer confidence was associated with an increased risk of nonusage attrition.

CONCLUSIONS

My Food & Mood version 3.0, a dietary intervention delivered via smartphone app with self-monitoring tools for diet quality and mood monitoring, was the version with greatest engagement in a population with low mood or depression. The iterative design techniques employed and analysis of feedback from participants resulted in a program that achieved lower rates of nonusage attrition and higher rates of intensity of use.

Mediterranean Lifestyle to Promote Physical, Mental, and Environmental Health: The Case of Chile

Chile is currently experiencing a progressive epidemiological transition towards chronic diseases. In this country, >50% of annual deaths are attributed to cardiovascular disease and cancer. Moreover, health surveys have shown high prevalence of obesity, diabetes, hypertension, and elevated cardiovascular disease risk. In addition, mental health issues are also frequent among Chilean adults. On the other hand, the agri-food system contributes to 21-37% of greenhouse gases emissions worldwide. Overall, current health and food chain situation calls out for design and implementation of evidence-based feasible and effective nutritional interventions needed to promote physical and mental health along with addressing food sustainability in Chile. Nowadays, the Mediterranean diet is recognized as one of the healthiest dietary patterns based on observational and interventional studies linked to a wide variety of health outcomes. However, a Mediterranean lifestyle goes well beyond food intake: it includes promotion of psychosocial resources, community life as well as cultural traditions. Indeed, Mediterranean lifestyle is a true modus vivendi that integrally promotes physical, mental, and social well-being. In addition, the Mediterranean diet stands out for its environmental sustainability because it is characterized mainly as a plant-based dietary pattern with low carbon and water footprints. Remarkably, Central Chile has a Mediterranean-like setting with plant and animal food production and availability patterns comparable to those present in countries located around the Mediterranean Sea. Therefore, this article reviews how promotion of Mediterranean lifestyle adherence in Chile offers great potential for management of the ongoing epidemiological transition to chronic diseases as well to promote psychological well-being within a unique food system and dietary sustainability vision for this Latin American country.

Investigating Whether the Mediterranean Dietary Pattern Is Integrated in Routine Dietetic Practice for Management of Chronic Conditions: A National Survey of Dietitians

Evidence supports recommending the Mediterranean dietary pattern (MDP) in the management of cardiovascular disease (CVD), type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD) and solid organ transplant (SOT). However, the evidence-practice gap is unclear within non-Mediterranean countries. We investigated integration of MDP in Australian dietetic practice, and barriers and enablers to MDP implementation for chronic disease management. Dietitians managing CVD, T2D, NAFLD and/or SOT patients (n = 182, 97% female) completed an online survey in November 2019. Fewer than 50% of participants counsel patients with CVD (48%), T2D (26%), NAFLD (31%) and SOT (0–33%) on MDP in majority of their practice. MDP principles always recommended by >50% of participants were promoting vegetables and fruit and limiting processed foods and sugary drinks. Principles recommended sometimes, rarely or never by >50% of participants included limiting red meat and including tomatoes, onion/garlic and liberal extra virgin olive oil. Barriers to counselling on MDP included consultation time and competing priorities. Access to evidence, professional development and education resources were identified enablers. An evidence-practice gap in Australian dietetic practice exists with <50% of participants routinely counselling relevant patient groups on MDP. Strategies to support dietitians to counsel complex patients on MDP within limited consultations are needed.

The Health Benefits of Dietary Fibre

Background: Dietary fibre consists of non-digestible forms of carbohydrate, usually as polysaccharides that originate from plant-based foods. Over recent decades, our diet within Westernised societies has changed radically from that of our hominid ancestors, with implications for our co-evolved gut microbiota. This includes increased ingestion of ultra-processed foods that are typically impoverished of dietary fibre, and associated reduction in the intake of fibre-replete plant-based foods. Over recent decades, there has been a transformation in our understanding of the health benefits of dietary fibre. Objective: To explore the current medical literature on the health benefits of dietary fibre, with a focus on overall metabolic health. Data Sources: We performed a narrative review, based on relevant articles written in English from a PubMed search, using the terms ‘dietary fibre and metabolic health’. Results: In the Western world, our diets are impoverished of fibre. Dietary fibre intake associates with overall metabolic health (through key pathways that include insulin sensitivity) and a variety of other pathologies that include cardiovascular disease, colonic health, gut motility and risk for colorectal carcinoma. Dietary fibre intake also correlates with mortality. The gut microflora functions as an important mediator of the beneficial effects of dietary fibre, including the regulation of appetite, metabolic processes and chronic inflammatory pathways. Conclusions: Multiple factors contribute to our fibre-impoverished modern diet. Given the plethora of scientific evidence that corroborate the multiple and varied health benefits of dietary fibre, and the risks associated with a diet that lacks fibre, the optimization of fibre within our diets represents an important public health strategy to improve both metabolic and overall health. If implemented successfully, this strategy would likely result in substantial future health benefits for the population.