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The Permanente Journal Jun 2022B vitamins are a group of 8 water-soluble vitamins. The body does not store them, so they need to be replaced daily. B vitamins are found in animal proteins, dairy... (Review)
Review
B vitamins are a group of 8 water-soluble vitamins. The body does not store them, so they need to be replaced daily. B vitamins are found in animal proteins, dairy products, leafy green vegetables, and beans. Overall, their function can generally be divided into catabolic metabolism, leading to energy production, and anabolic metabolism, resulting in bioactive molecules. They are critical cofactors for axonal transport, synthesis of neurotransmitters, and many cellular metabolic pathways. B vitamins are cofactors for many essential enzymes involved in the biosynthesis of RNA and DNA. B vitamin deficiencies have been considered as etiological factors in the development of various neurologic disorders and a broad spectrum of pathological states. Reductions in food intake and absorption efficiency in some populations, including the geriatric population, may warrant attention to their dietary B vitamin levels. Most B vitamins are generally safe even at intake levels reached with fortified food or supplements.
Topics: Aged; Animals; Diet; Dietary Supplements; Humans; Vitamin B Complex
PubMed: 35933667
DOI: 10.7812/TPP/21.204 -
Nutrients Nov 2020B group vitamins represent essential micronutrients for myriad metabolic and regulatory processes required for human health, serving as cofactors used by hundreds of... (Review)
Review
B group vitamins represent essential micronutrients for myriad metabolic and regulatory processes required for human health, serving as cofactors used by hundreds of enzymes that carry out essential functions such as energy metabolism, DNA and protein synthesis and other critical functions. B vitamins and their corresponding vitamers are universally essential for all cellular life forms, from bacteria to humans. Humans are unable to synthesize most B vitamins and are therefore dependent on their diet for these essential micronutrients. More recently, another source of B vitamins has been identified which is derived from portions of the 10 bacterial cells inhabiting the gastrointestinal tract. Here we review the expanding literature examining the relationship between B vitamins and the immune system and diverse cancers. Evidence of B vitamin's role in immune cell regulation has accumulated in recent years and may help to clarify the disparate findings of numerous studies attempting to link B vitamins to cancer development. Much work remains to be carried out to fully clarify these relationships as the complexity of B vitamins' essential functions complicates an unequivocal assessment of their beneficial or detrimental effects in inflammation and cancers.
Topics: Animals; Gastrointestinal Microbiome; Humans; Immune System; Metabolic Networks and Pathways; Neoplasms; Vitamin B Complex
PubMed: 33158037
DOI: 10.3390/nu12113380 -
Nutrients Apr 2019This narrative review explores the relationship between sleep and nutrition. Various nutritional interventions have been shown to improve sleep including high... (Review)
Review
This narrative review explores the relationship between sleep and nutrition. Various nutritional interventions have been shown to improve sleep including high carbohydrate, high glycaemic index evening meals, melatonin, tryptophan rich protein, tart cherry juice, kiwifruit and micronutrients. Sleep disturbances and short sleep duration are behavioural risk factors for inflammation, associated with increased risk of illness and disease, which can be modified to promote sleep health. For sleep to have a restorative effect on the body, it must be of adequate duration and quality; particularly for athletes whose physical and mental recovery needs may be greater due to the high physiological and psychological demands placed on them during training and competition. Sleep has been shown to have a restorative effect on the immune system, the endocrine system, facilitate the recovery of the nervous system and metabolic cost of the waking state and has an integral role in learning, memory and synaptic plasticity, all of which can impact both athletic recovery and performance. Functional food-based interventions designed to enhance sleep quality and quantity or promote general health, sleep health, training adaptations and/or recovery warrant further investigation.
Topics: Antioxidants; Athletes; Athletic Performance; Circadian Rhythm; Diet; Dietary Carbohydrates; Fruit; Glycemic Index; Humans; Melatonin; Nutritional Physiological Phenomena; Prunus avium; Sleep; Sleep Wake Disorders; Tryptophan; Vitamin B Complex
PubMed: 30979048
DOI: 10.3390/nu11040822 -
BioMed Research International 2021Damage and regeneration naturally occur in the peripheral nervous system. The neurotropic B vitamins thiamine (B1), pyridoxine (B6), and cobalamin (B12) are key players,... (Review)
Review
Damage and regeneration naturally occur in the peripheral nervous system. The neurotropic B vitamins thiamine (B1), pyridoxine (B6), and cobalamin (B12) are key players, which maintain the neuronal viability in different ways. Firstly, they constantly protect nerves against damaging environmental influences. While vitamin B1 acts as a site-directed antioxidant, vitamin B6 balances nerve metabolism, and vitamin B12 maintains myelin sheaths. However, nerve injury occurs at times, because of an imbalance between protective factors and accumulating stress and noxae. This will result in the so-called Wallerian degeneration process. The presence of vitamins B1, B6, and B12 paves the way out to the following important regeneration by supporting the development of new cell structures. Furthermore, vitamin B1 facilitates the usage of carbohydrates for energy production, whereas vitamin B12 promotes nerve cell survival and remyelination. Absence of these vitamins will favor permanent nerve degeneration and pain, eventually leading to peripheral neuropathy.
Topics: Animals; Humans; Nerve Growth Factors; Nerve Regeneration; Vitamin B Complex
PubMed: 34337067
DOI: 10.1155/2021/9968228 -
Nutrients Jan 2016The B-vitamins comprise a group of eight water soluble vitamins that perform essential, closely inter-related roles in cellular functioning, acting as co-enzymes in a... (Review)
Review
The B-vitamins comprise a group of eight water soluble vitamins that perform essential, closely inter-related roles in cellular functioning, acting as co-enzymes in a vast array of catabolic and anabolic enzymatic reactions. Their collective effects are particularly prevalent to numerous aspects of brain function, including energy production, DNA/RNA synthesis/repair, genomic and non-genomic methylation, and the synthesis of numerous neurochemicals and signaling molecules. However, human epidemiological and controlled trial investigations, and the resultant scientific commentary, have focused almost exclusively on the small sub-set of vitamins (B9/B12/B6) that are the most prominent (but not the exclusive) B-vitamins involved in homocysteine metabolism. Scant regard has been paid to the other B vitamins. This review describes the closely inter-related functions of the eight B-vitamins and marshals evidence suggesting that adequate levels of all members of this group of micronutrients are essential for optimal physiological and neurological functioning. Furthermore, evidence from human research clearly shows both that a significant proportion of the populations of developed countries suffer from deficiencies or insufficiencies in one or more of this group of vitamins, and that, in the absence of an optimal diet, administration of the entire B-vitamin group, rather than a small sub-set, at doses greatly in excess of the current governmental recommendations, would be a rational approach for preserving brain health.
Topics: Brain; Humans; Vitamin B Complex; Vitamin B Deficiency
PubMed: 26828517
DOI: 10.3390/nu8020068 -
International Journal of Molecular... Jan 2020Riboflavin (RF) is a water-soluble member of the B-vitamin family. Sufficient dietary and supplemental RF intake appears to have a protective effect on various medical... (Review)
Review
Riboflavin (RF) is a water-soluble member of the B-vitamin family. Sufficient dietary and supplemental RF intake appears to have a protective effect on various medical conditions such as sepsis, ischemia etc., while it also contributes to the reduction in the risk of some forms of cancer in humans. These biological effects of RF have been widely studied for their anti-oxidant, anti-aging, anti-inflammatory, anti-nociceptive and anti-cancer properties. Moreover, the combination of RF and other compounds or drugs can have a wide variety of effects and protective properties, and diminish the toxic effect of drugs in several treatments. Research has been done in order to review the latest findings about the link between RF and different clinical aberrations. Since further studies have been published in this field, it is appropriate to consider a re-evaluation of the importance of RF in terms of its beneficial properties.
Topics: Animals; Dietary Supplements; Drug Interactions; Functional Food; Humans; Riboflavin; Vitamin B Complex
PubMed: 32023913
DOI: 10.3390/ijms21030950 -
The Cochrane Database of Systematic... Mar 2018Vitamin B deficiency is common, and the incidence increases with age. Most people with vitamin B deficiency are treated in primary care with intramuscular (IM) vitamin... (Review)
Review
BACKGROUND
Vitamin B deficiency is common, and the incidence increases with age. Most people with vitamin B deficiency are treated in primary care with intramuscular (IM) vitamin B. Doctors may not be prescribing oral vitamin B formulations because they may be unaware of this option or have concerns regarding its effectiveness.
OBJECTIVES
To assess the effects of oral vitamin B versus intramuscular vitamin B for vitamin B deficiency.
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase, and LILACS, as well as the WHO ICTRP and ClinicalTrials.gov. The latest search date was 17 July 2017. We applied no language restrictions. We also contacted authors of relevant trials to enquire about other published or unpublished studies and ongoing trials.
SELECTION CRITERIA
Randomised controlled trials (RCTs) comparing the effect of oral versus IM vitamin B for vitamin B deficiency.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures expected by Cochrane. Our primary outcomes were serum vitamin B levels, clinical signs and symptoms of vitamin B deficiency, and adverse events. Secondary outcomes were health-related quality of life, acceptability to patients, haemoglobin and mean corpuscular volume, total homocysteine and serum methylmalonic acid levels, and socioeconomic effects. We used GRADE to assess the quality of the evidence for important outcomes. We did not perform meta-analyses due to the small number of included trials and substantial clinical heterogeneity.
MAIN RESULTS
Three RCTs met our inclusion criteria. The trials randomised 153 participants (74 participants to oral vitamin B and 79 participants to IM vitamin B). Treatment duration and follow-up ranged between three and four months. The mean age of participants ranged from 38.6 to 72 years. The treatment frequency and daily dose of vitamin B in the oral and IM groups varied among trials. Only one trial had low or unclear risk of bias across all domains and outcome measures. Two trials reported data for serum vitamin B levels. The overall quality of evidence for this outcome was low due to serious imprecision (low number of trials and participants). In two trials employing 1000 μg/day oral vitamin B, there was no clinically relevant difference in vitamin B levels when compared with IM vitamin B. One trial used 2000 μg/day vitamin B and demonstrated a mean difference of 680 pg/mL (95% confidence interval 392.7 to 967.3) in favour of oral vitamin B. Two trials reported data on adverse events (very low-quality evidence due to risk of performance bias, detection bias, and serious imprecision). One trial stated that no treatment-related adverse events were seen in both the oral and IM vitamin B groups. One trial reported that 2 of 30 participants (6.7%) in the oral vitamin B group left the trial early due to adverse events. Orally taken vitamin B showed lower treatment-associated costs than IM vitamin B in one trial (low-quality evidence due to serious imprecision). No trial reported on clinical signs and symptoms of vitamin B deficiency, health-related quality of life, or acceptability of the treatment scheme.
AUTHORS' CONCLUSIONS
Low quality evidence shows oral and IM vitamin B having similar effects in terms of normalising serum vitamin B levels, but oral treatment costs less. We found very low-quality evidence that oral vitamin B appears as safe as IM vitamin B. Further trials should conduct better randomisation and blinding procedures, recruit more participants, and provide adequate reporting. Future trials should also measure important outcomes such as the clinical signs and symptoms of vitamin B deficiency, health related-quality of life, socioeconomic effects, and report adverse events adequately, preferably in a primary care setting.
Topics: Administration, Oral; Aged; Humans; Injections, Intramuscular; Randomized Controlled Trials as Topic; Vitamin B 12; Vitamin B 12 Deficiency; Vitamin B Complex
PubMed: 29543316
DOI: 10.1002/14651858.CD004655.pub3 -
BMC Medicine Apr 2021Whether a modestly elevated homocysteine level is causally associated with an increased risk of cardiovascular disease remains unestablished. We conducted a Mendelian...
BACKGROUND
Whether a modestly elevated homocysteine level is causally associated with an increased risk of cardiovascular disease remains unestablished. We conducted a Mendelian randomization study to assess the associations of circulating total homocysteine (tHcy) and B vitamin levels with cardiovascular diseases in the general population.
METHODS
Independent single nucleotide polymorphisms associated with tHcy (n = 14), folate (n = 2), vitamin B6 (n = 1), and vitamin B12 (n = 14) at the genome-wide significance level were selected as instrumental variables. Summary-level data for 12 cardiovascular endpoints were obtained from genetic consortia, the UK Biobank study, and the FinnGen consortium.
RESULTS
Higher genetically predicted circulating tHcy levels were associated with an increased risk of stroke. For each one standard deviation (SD) increase in genetically predicted tHcy levels, the odds ratio (OR) was 1.11 (95% confidence interval (CI), 1.03, 1.21; p = 0.008) for any stroke, 1.26 (95% CI, 1.05, 1.51; p = 0.013) for subarachnoid hemorrhage, and 1.11 (95% CI, 1.03, 1.21; p = 0.011) for ischemic stroke. Higher genetically predicted folate levels were associated with decreased risk of coronary artery disease (OR, 0.88; 95% CI, 0.78, 1.00, p = 0.049) and any stroke (OR, 0.86; 95% CI, 0.76, 0.97, p = 0.012). Genetically predicted increased vitamin B6 levels were associated with a reduced risk of ischemic stroke (OR, 0.88; 95% CI, 0.81, 0.97, p = 0.009). None of these associations persisted after multiple testing correction. There was no association between genetically predicted vitamin B12 and cardiovascular disease.
CONCLUSIONS
This study reveals suggestive evidence that B vitamin therapy and lowering of tHcy may reduce the risk of stroke, particularly subarachnoid hemorrhage and ischemic stroke.
Topics: Cardiovascular Diseases; Folic Acid; Homocysteine; Humans; Mendelian Randomization Analysis; Risk Factors; Vitamin B 12; Vitamin B Complex
PubMed: 33888102
DOI: 10.1186/s12916-021-01977-8 -
Nutrients Sep 2022The importance of B complex vitamins starts early in the human life cycle and continues across its different stages. At the same time, numerous reports have emphasized... (Review)
Review
The importance of B complex vitamins starts early in the human life cycle and continues across its different stages. At the same time, numerous reports have emphasized the critical role of adequate B complex intake. Most studies examined such issues concerning a specific vitamin B or life stage, with the majority reporting the effect of either excess or deficiency. Deep insight into the orchestration of the eight different B vitamins requirements is reviewed across the human life cycle, beginning from fertility and pregnancy and reaching adulthood and senility, emphasizing interactions among them and underlying action mechanisms. The effect of sex is also reviewed for each vitamin at each life stage to highlight the different daily requirements and/or outcomes. Thiamine, riboflavin, niacin, pyridoxine, and folic acid are crucial for maternal and fetal health. During infancy and childhood, B vitamins are integrated with physical and psychological development that have a pivotal impact on one's overall health in adolescence and adulthood. A higher intake of B vitamins in the elderly is also associated with preventing some aging problems, especially those related to inflammation. All supplementation should be carefully monitored to avoid toxicity and hypervitaminosis. More research should be invested in studying each vitamin individually concerning nutritional disparities in each life stage, with extensive attention paid to cultural differences and lifestyles.
Topics: Adolescent; Adult; Aged; Child; Female; Folic Acid; Humans; Male; Niacin; Pantothenic Acid; Pregnancy; Pyridoxine; Riboflavin; Sex Characteristics; Thiamine; Vitamin B 12; Vitamin B Complex
PubMed: 36235591
DOI: 10.3390/nu14193940 -
The Journal of Nutrition Aug 2017Although frank symptomatic biotin deficiency is rare, some evidence suggests that marginal biotin deficiency occurs spontaneously in a substantial proportion of women... (Review)
Review
Although frank symptomatic biotin deficiency is rare, some evidence suggests that marginal biotin deficiency occurs spontaneously in a substantial proportion of women during normal human pregnancy and might confer an increased risk of birth defects. Herein I review ) advances in assessing biotin status, including the relation between acylcarnitine excretion and biotin status; ) recent studies of biotin status in pregnancy; ) advances in understanding the role of biotin in gene expression and the potential roles of biotinylated proteins that are neither histones nor carboxylases; and ) novel large-dose biotin supplementation as therapy for multiple sclerosis. The review concludes with a summary of recent studies that have reported potentially dangerous erroneous results in individuals consuming large amounts of biotin for measurements of various plasma hormones for common clinical assays that use streptavidin-biotin technology.
Topics: Animals; Biotin; Biotinylation; Carnitine; Female; Gene Expression; Hormones; Humans; Multiple Sclerosis; Nutritional Status; Pregnancy; Pregnancy Complications; Streptavidin; Vitamin B Complex
PubMed: 28701385
DOI: 10.3945/jn.116.238956