Editorial: Nutrition, Metabolic Pathways, and Mental Health—New Directions from Micronutrients to Lifestyle

Shalini Mani^1*Samiksha Wasnik²MANISHA SINGH¹

• ¹Jaypee Institute of Information Technology, Noida, India
• ²Loma Linda University Medical Center, Loma Linda, United States

Following this increasing appreciation of the relationship between diet and mental health, this current Research Topic "Nutrition and Mood Disorders" of Frontiers in Nutrition presents a collection of 12 articles, covering large-scale epidemiological studies, randomised trials, systematic reviews, as well as mechanistic studies, providing a comprehensive understanding of the intricate relationship between diet and mental health. These inputs include a variety of populations, cultural backgrounds, and scientific frameworks, but come together on a common consent that nutrition is a critical determinant of mental health and a potential therapeutic target. These 12 studies made the following important points: Chu et al. investigated sex-specific variations in the relationship between dietary riboflavin (vitamin B2) consumption and depression or suicidal ideation within a substantial NHANES-based population (n = 29,466). The analysis revealed a non-linear inverse relationship evident exclusively below an intake threshold of approximately 1. Gu et al. utilised CHARLS data to examine the correlation between the Lipid Accumulation Product (LAP) an indicator of visceral adiposity and the prevalence of depression in middle-aged and older Chinese men. The study revealed a notable U-shaped relationship, where both low and high LAP values were associated with an increased risk of depression, suggesting that a moderate amount of body fat may be beneficial for mood regulation. These findings highlight the complex interaction between body-fat distribution and emotional well-being.Li and Lan examined NHANES data from 2007 to 2016, analyzing over 18,000 U.S. adults to assess the correlation between dietary lycopene consumption and depression. They discovered that increased lycopene intake was associated with a reduced likelihood of depression, although the benefits diminished at higher levels, forming a U-shaped relationship. The authors suggested that this association may involve antioxidant and anti-inflammatory pathways and advocated for longitudinal investigations to clarify causality.Rana et al. evaluated observational and interventional research investigating the roles of natural sulfur-containing compounds, such as sulforaphane, taurine, allyl sulfides, hydrogen sulfide donors, and sulfated metabolites, in mental and neurological health. He highlighted evidence suggesting that consuming sulfur-rich foods may protect the brain, reduce inflammation, and inhibit oxidative stress, potentially benefiting conditions such as schizophrenia, depression, and anxiety. The study emphasised the neuroprotective and neurotransmission-modulating effects of these compounds while noting existing research gaps in translating these biochemical findings into therapeutic applications.He et al. evaluated the correlation between blood uric acid concentrations and depression using NHANES data from more than 23,000 participants. The study found that individuals with higher uric acid levels were less likely to experience depression, particularly among older adults, individuals with heart disease, and certain ethnic groups. The authors also explored potential mechanisms involving oxidative stress and purinergic signalling and acknowledged the limitations of cross-sectional designs in establishing causality.Ebrahimi et al. investigated the correlation between lifestyle risk scores-encompassing diet, physical activity, sleep, smoking habits, and social background factors-and mental health outcomes in overweight and obese Iranian women. The study found that higher composite lifestyle risk scores were associated with poorer mental health indicators, emphasising the importance of addressing multiple lifestyle domains rather than isolated habits. These findings highlight the value of integrated lifestyle interventions in improving mood and overall well-being within this demographic.Ghabashi examined the correlation between nutritional awareness and generalised anxiety disorder among young adults in Saudi Arabia. The cross-sectional study revealed that increased nutrition knowledge correlated with reduced GAD symptoms, indicating that improving nutritional education may support national preventative mental health initiatives in accordance with Saudi Vision 2030.Lv et al. investigated the correlation between serum β-carotene concentrations and suicidal thoughts in adults utilizing cross-sectional data. The findings indicated an inverse correlation, with elevated β-carotene levels associated with less suicidal ideation. The authors suggested antioxidant level as a possible protective mechanism and recommended long-term studies to further investigate this relationship.Collectively, the articles featured in this special issue underscore the intricate interplay between dietary components, nutritional biomarkers, and mental health outcomes. Future studies should adopt longitudinal and mechanistic designs, harmonize nutritional and psychological assessments, and explore sex-and culture-specific factors to translate nutritional psychiatry insights into effective preventive and therapeutic interventions.