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Vitamins & Minerals

Vitamin B ComplexEvidence & Dosage

Methylation, B12, methylfolate, energy, and neurotransmitter synthesis.

Studies last updated

Evidence at a glance

Total studies
544
With abstract
49
Meta / Systematic / RCT
107
Highly cited
50
Publication years
1955–2026

Vitamin B Complex in the context of Vitamins & Minerals

This topic is part of our "Vitamins & Minerals" world. There you'll find methodology, evidence and the highest-impact levers — plus the order in which they sensibly build on each other.

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Top studies on Vitamin B Complex

Ranked by influential-citation count and publication year.

  1. Vitamin Supplementation and Dementia: A Systematic Review.

    Nutrients2022systematic85 influential citations

    BACKGROUND: Dementia is a syndrome characterized by progressive cognitive impairment that interferes with independent function in daily activities. Symptoms of dementia depend on its cause and vary greatly between individuals. There is…

  2. Improvement in cervical dysplasia associated with folic acid therapy in users of oral contraceptives.

    Am J Clin Nutr1982n=47RCT70 influential citations

    Forty-seven young women with mild or moderate dysplasia of the uterine cervix (cervical intraepithelial neoplasia) diagnosed by cervical smears, received oral supplements of folic acid, 10 mg, or a placebo (ascorbic acid, 10 mg) daily for…

  3. Brain delivery of supplemental docosahexaenoic acid (DHA): A randomized placebo-controlled clinical trial.

    EBioMedicine2020n=33rct64 influential citations

    BACKGROUND: Past clinical trials of docosahexaenoic Acid (DHA) supplements for the prevention of Alzheimer's disease (AD) dementia have used lower doses and have been largely negative. We hypothesized that larger doses of DHA are needed…

  4. Effects of Vitamin B12 Supplementation on Cognitive Function, Depressive Symptoms, and Fatigue: A Systematic Review, Meta-Analysis, and Meta-Regression.

    Nutrients2021n=627Meta-Analysis64 influential citations

    Vitamin B12 is often used to improve cognitive function, depressive symptoms, and fatigue. In most cases, such complaints are not associated with overt vitamin B12 deficiency or advanced neurological disorders and the effectiveness of…

    Finding: Vitamin B12 supplementation was likely ineffective for improving cognitive function in patients without advanced neurological disorders.

  5. Water-Soluble Vitamins: Hypo- and Hypervitaminosis in Pediatric Population.

    Pharmaceutics2025D62 influential citations

    Water-soluble vitamins, comprising the B-complex vitamins and vitamin C, are essential for normal growth, cellular metabolism, and immune function in pediatric populations. Due to limited storage in the body, these vitamins require…

  6. A Combinational Therapy for Preventing and Delaying the Onset of Alzheimer's Disease: A Focus on Probiotic and Vitamin Co-Supplementation.

    Antioxidants (Basel, Switzerland)2024D54 influential citations

    Alzheimer's disease is a progressive neurodegenerative disorder with a complex etiology, and effective interventions to prevent or delay its onset remain a global health challenge. In recent years, there has been growing interest in the…

  7. Vitamin intake and periodontal disease: a meta-analysis of observational studies.

    BMC Oral Health2024n=74,488Meta-Analysis52 influential citations

    <h4>Objective</h4>A meta-analysis was performed to assess the epidemiological correlation between dietary intake of various types of vitamin intake and the risk of periodontal disease.<h4>Methods</h4>A comprehensive computerized search was…

  8. Biological properties of vitamin B(12).

    Nutr Res Rev2025review50 influential citations

    Vitamin B12, cobalamin, is indispensable for humans owing to its participation in two biochemical reactions: the conversion of l-methylmalonyl coenzyme A to succinyl coenzyme A, and the formation of methionine by methylation of…

  9. Nutritional supplements and mother's milk composition: a systematic review of interventional studies.

    Int Breastfeed J2021n=1,320Systematic Review49 influential citations

    Background This study aims to systematically review the effects of maternal vitamin and/or mineral supplementation on the content of breast milk. Methods We systematically searched electronic databases including Medline via PubMed, Scopus…

  10. The Impact of Vitamin Deficiencies on Oral Manifestations in Children.

    Dentistry journal2024D47 influential citations

    Vitamins play a vital role in human health, particularly in the development and maintenance of oral health in children. These nutrients are broadly categorized into fat-soluble and water-soluble types, crucial for children's well-being.…

Frequently asked

What dosage was studied?
• Vitamin supplementation (folic acid, vitamin B12, thiamine, vitamin D, vitamin E, vitamin C, ascorbic acid, B-complex vitamins) (Varied by included studies; low-dose vitamin E and vitamin C noted, high-dose vitamin E noted) • Oral folic acid supplementation (10 mg daily) • Docosahexaenoic acid (DHA) supplementation plus vitamin B complex (2,152 mg DHA per day; vitamin B12 1 mg/day, vitamin B6 100 mg/day, folic acid 800 mcg/day)
Are there safety considerations for Vitamin B Complex?
• Not reported • No adverse events reported in the abstract. • Not reported in the abstract. • Not reported in abstract

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