Putative role of vitamin D in the mechanism of alcoholism and other addictions - a hypothesis

Potential roles for vitamin D in preventing and treating impulse control disorders, behavioral addictions, and substance use disorders: A scoping review

Vitamin D deficiency is a problem of endemic proportions. Vitamin D is a major regulator of dopaminergic and serotonergic circuits, pathways implicated in addictive disorders. This scoping review (OSF registered as 67yhb) examines preclinical and clinical studies exploring relationships between vitamin D in impulse control disorders, behavioral addictions, and substance use disorders. We searched Ovid MEDLINE, Embase, APA PsycInfo, Cochrane Library, Web of Science, and Scopus databases. We extracted and summarized quantitative and qualitative data through a narrative synthesis and assessed the quality of studies using the Joanna Briggs Institute (JBI) and SYRCLE (Systematic Review Centre for Laboratory Animal Experimentation) criteria. Of 5,442 initial records identified, 28 preclinical and clinical studies were included. For most conditions, we found a negative relationship between vitamin D levels and symptom presence and/or severity. While data suggest a potential beneficial effect of vitamin D on preventing or treating these conditions, there were significant limitations identified by the JBI and SYRCLE assessments. Future studies should include impulse control disorders and other under-explored conditions, address heterogeneity regarding forms, doses, and duration of exposures to vitamin D, and explore vitamin D's potential therapeutic mechanisms.

The Potential of N-acetyl Cysteine in Behavioral Addictions and Related Compulsive and Impulsive Behaviors and Disorders: a Scoping Review

Purpose of Review

Behavioral addictions (also termed disorders due to addictive behaviors) contain impulsive and compulsive features and have been shown to involve glutamate dysregulation. N-acetylcysteine (NAC), a well-tolerated cysteine pro-drug and antioxidant, may reduce addictive behaviors by restoring glutamate homeostasis. The current review details and discusses the use of NAC in behavioral addictions and related impulsive and compulsive behaviors, including gambling disorder, problematic use of the internet, problematic video gaming, compulsive sexual behavior, problematic shopping/buying, problematic stealing, repetitive self-injurious behavior, and binge eating disorder.

Recent Findings

Preliminary results have indicated the usefulness of NAC in gambling disorder, self-injurious behaviors, and compulsive sexual behaviors. Preclinical studies indicate that NAC is effective in improving binge eating behavior, but clinical trials are limited to a small open-label trial and case report. Studies are lacking on the efficacy of NAC in problematic use of the internet, problematic video gaming, problematic stealing, and problematic shopping/buying.

Summary

NAC demonstrates potential for use in behavioral addictions and compulsive behaviors, particularly in gambling disorder and self-injury. However, more studies are needed to assess the effectiveness of NAC in other behavioral addictions and the mechanisms by which NAC improves these conditions.

Vitamin D status and associations with substance use patterns among people with severe substance use disorders in Western Norway

Chronic and harmful substance use is associated with a cluster of harms to health, including micronutrient deficiencies. Maintaining adequate levels of vitamin D is important for musculoskeletal and other aspects of health. In this prospective longitudinal cohort study, 666 participants drawn from outpatient opioid agonist therapy (OAT) clinics and community care clinics for substance use disorder in Western Norway were assessed annually for determination of serum 25-hydroxyvitamin D [s-25(OH)D] levels. Fifty-seven percent were deficient at baseline (s-25(OH)D < 50 nmol/l), and 19% were severely deficient (s-25(OH)D < 25 nmol/l). Among those deficient/severely deficient at baseline, 70% remained deficient/severely deficient at the last measurement (mean duration 714 days). Substance use patterns and dosage of opioids for OAT were not associated with vitamin D levels. One exception was found for cannabis, where consumption on a minimum weekly basis was associated with lower levels at baseline (mean difference: -5.2 nmol/l, 95% confidence interval [CI]: -9.1, - 1.3), but without clear time trends (mean change per year: 1.4 nmol/l, CI: - 0.86, 3.7). The high prevalence of sustained vitamin D deficiency in this cohort highlights the need for targeted monitoring and supplementation for this and similar at-risk populations.