scholarly journals Plasma total homocysteine status of vegetarians compared with omnivores: a systematic review and meta-analysis

2013 ◽  
Vol 109 (5) ◽  
pp. 785-794 ◽  
Author(s):  
Derek Obersby ◽  
David C. Chappell ◽  
Andrew Dunnett ◽  
Amalia A. Tsiami

There is strong evidence indicating that elevated plasma total homocysteine (tHcy) levels are a major independent biomarker and/or a contributor to chronic conditions, such as CVD. A deficiency of vitamin B12can elevate homocysteine. Vegetarians are a group of the population who are potentially at greater risk of vitamin B12deficiency than omnivores. This is the first systematic review and meta-analysis to appraise a range of studies that compared the homocysteine and vitamin B12levels of vegetarians and omnivores. The search methods employed identified 443 entries, from which, by screening using set inclusion and exclusion criteria, six eligible cohort case studies and eleven cross-sectional studies from 1999 to 2010 were revealed, which compared concentrations of plasma tHcy and serum vitamin B12of omnivores, lactovegetarians or lacto-ovovegetarians and vegans. Of the identified seventeen studies (3230 participants), only two studies reported that vegan concentrations of plasma tHcy and serum vitamin B12did not differ from omnivores. The present study confirmed that an inverse relationship exists between plasma tHcy and serum vitamin B12, from which it can be concluded that the usual dietary source of vitamin B12is animal products and those who choose to omit or restrict these products are destined to become vitamin B12deficient. At present, the available supplement, which is usually used for fortification of food, is the unreliable cyanocobalamin. A well-designed study is needed to investigate a reliable and suitable supplement to normalise the elevated plasma tHcy of a high majority of vegetarians. This would fill the gaps in the present nutritional scientific knowledge.

2007 ◽  
Vol 27 (5) ◽  
pp. 476-488 ◽  
Author(s):  
Bradley L. Urquhart ◽  
Andrew A. House

Elevated plasma total homocysteine (tHcy) is a risk factor for cardiovascular disease; however, in light of several recent randomized trials, the issue of causality has been cast into doubt. Patients with end-stage renal disease are particularly interesting as they consistently have elevated tHcy and their leading causes of morbidity and mortality are related to cardiovascular disease. In the present article, we review the early evidence for the homocysteine theory of atherosclerosis, homocysteine metabolism, mechanisms of toxicity, and pertinent available clinical investigations. Where appropriate, the sparse evidence of homocysteine in peritoneal dialysis is reviewed. We conclude by addressing the difficulties associated with lowering plasma tHcy in patients with end-stage renal disease and suggest some novel methods for lowering tHcy in this resistant population. Finally, to address the issue of causality, we recommend that clinicians and scientists await the results of the FAVORIT trial before abandoning homocysteine as a modifiable risk factor for cardiovascular disease, as this study has recruited patients from a population with consistently elevated plasma tHcy who are known to respond to vitamin therapy.


Pteridines ◽  
2007 ◽  
Vol 18 (1) ◽  
pp. 122-127
Author(s):  
Bakhouche Houcher ◽  
Mirande Candito ◽  
Pierre Gibelin

Abstract Elevated plasma total homocysteine (tHcy) is an independent risk factor for cardiovascular disease (CVD). Also known is that plasma folate and vitamin B12 influence homocysteine metabolism as cosubstrate and cofactor, respectively. This population-based study was conducted to evaluate the plasma concentrations of tHcy, folate, and vitamin B12 in 54 older patients aged ≥51 years (40 males; 14 females) of Nice hospital cardiology service. After excluding cases with a serum creatinine >120 mmol/L, we established the test properties of a plasma tHcy concentration <15 μmol/L (Group 1) or ≥15 μmol/L (Group 2). In the population aged ≥51 years, plasma tHcy was higher in women (18.0 μmol/L) than in men (15.5 μmol/L; not significant), conversely, serum vitamin B12 was higher in men (376.9 pg/ml) than in women (340.7 pg/ml; not significant). Average plasma tHcy was 11.5 μmol/L in Group 1 and 21.6 μmol/L in Group 2. Vice versa, serum vitamin B12 was higher in Group 1 (419.5 pg/ml) than in Group 2 (307.2 pg/ml) (p <0.05). Correlation analysis (Pearson's r) in the total study population (20-84 years) indicated an inverse correlation between serum folate and age (r = -0.231, p <0.05). In the subjects, aged ≥51 years, there was a significant negative correlation between age and tHcy levels (r = -0.283, p <0.05) and serum vitamin B12 concentrations (r = -0.326, p <0.01) but not with serum folate. However, in subjects with tHcy <15 μmol/L, a significant inverse correlation existed between plasma tHcy and serum folate (r = -0.455; p <0.05). In conclusion, these results highlight the relevance of the vitamin status and particularly of folate levels in the modulation of fasting tHcy levels in the patients with clinical hyperhomocysteinemia, defined as plasma tHcy >15 μmol/L.


2021 ◽  
Author(s):  
Michel Carlos Mocellin ◽  
Cintia Chaves Curioni ◽  
Alessandra da Silva Pereira ◽  
Simone Augusta Ribas ◽  
Michelle Teixeira Teixeira ◽  
...  

Abstract Background: Complex B vitamin deficiency are involved with several outcomes in fertility and pregnancy. In Brazil, the national prevalence rates of these micronutrients deficiencies in women at reproductive age was not known. Therefore, this study aims to systematically identify, select, evaluate, analyze and report the prevalence rates of complex B vitamins deficiencies in women at reproductive age in Brazil, and identify variables that may modify the outcome rates.Methods: A systematic review will be conducted guided by the following question: “What is the prevalence of vitamin B complex deficiencies in women at reproductive age in Brazil?”. The studies will be identified and selected from a literature search using electronic databases, consultation to researchers/specialists, as well as reference lists of eligible studies and reviews on the topic. Major eligibility criteria include observational cross-sectional and cohort studies performed in women with 10-49 years old from Brazil; pregnant and lactating mothers; and which that investigated the deficiency of complex B vitamins by laboratorial test. Two reviewers independently will perform the screening and selection of studies, to subsequently perform data extraction and risk assessment of bias. For data report, a narrative approach will be used to summarize the characteristics of the included studies and the individual prevalence found for each micronutrient tested, and if the studies are sufficiently homogeneous, a quantitative synthesis (meta-analysis) will be performed.Discussion: Identify the national and regional prevalence rates of complex B vitamins deficiencies allow the policy makers discuss, plan and implement public policy to prevent and/or reduces the rates, if they are larger, or at least highlight discussions about a program of screening the vitamins deficiencies in this specific population for to know the epidemiologic scenario among the years, serving as an indirect indicator of the socioeconomic and dietary patterns of this population. Also, specifically for folates, this study allows to compare the prevalence rates of deficiency of this vitamin before and after the mandatory fortification of wheat and corn flours implemented since 2004. Nevertheless, the evidence gathered may highlight the need for population-based studies to investigate the deficiency of these vitamins.Systematic review registration: PROSPERO registration number: CRD42020188474


2021 ◽  
Vol 13 ◽  
Author(s):  
Guili Zhang ◽  
Shuai Liu ◽  
Zhichao Chen ◽  
Zhihong Shi ◽  
Wenzheng Hu ◽  
...  

Background: Elevated plasma total homocysteine (tHcy) level, a known risk factor for vascular disease, is reported to be an independent risk factor for cognitive impairment and Alzheimer’s disease (AD) in most studies. tHcy may also be associated with dementia with Lewy bodies (DLB).Objective: To investigate the association between plasma tHcy levels and DLB or AD.Methods: This is a case-control study including 132 DLB patients, 264 AD patients, and 295 age-matched healthy controls. We used multivariate logistic regression model to analyze the data with adjustments for confounding variables.Results: The highest tHcy tertile (&gt;13.9 μmol/L) was significantly independently associated with DLB [adjusted odds ratio (OR): 4.65, 95% confidence interval (CI): 1.95–11.10, P = 0.001] and AD (adjusted OR: 1.82, 95% CI: 1.02–3.23, P = 0.041) compared to the lowest tertile (&lt;10.7 μmol/L). The cumulative frequency plots showed a shift in the distribution of the tHcy concentrations to higher values in patients with DLB compared to AD. The mean tHcy levels were stable and not altered by the duration of cognitive impairment prior to the collection of blood samples from DLB patients.Conclusion: Elevated plasma tHcy levels were independently associated with DLB, and the association was stronger for DLB than for AD. The lack of a relationship between tHcy levels and symptom duration may refute these observed associations being a consequence of DLB, and future longitudinal studies will be required to confirm whether tHcy plays a causative role in DLB.


Nutrients ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2286 ◽  
Author(s):  
Diego Marcos-Pérez ◽  
María Sánchez-Flores ◽  
Stefania Proietti ◽  
Stefano Bonassi ◽  
Solange Costa ◽  
...  

Serum vitamin D deficiency is widespread among older adults and is a potential modifiable risk factor for frailty. Moreover, frailty has been suggested as an intermediate step in the association between low levels of vitamin D and mortality. Hence, we conducted a systematic review of the literature and meta-analysis to test the possible association of low concentrations of serum 25-hydroxyvitamin D (25(OH)D), a marker of vitamin D status, with frailty in later life. We reviewed cross-sectional or longitudinal studies evaluating populations of older adults and identifying frailty by a currently validated scale. Meta-analyses were restricted to cross-sectional data from studies using Fried’s phenotype to identify frailty. Twenty-six studies were considered in the qualitative synthesis, and thirteen studies were included in the meta-analyses. Quantitative analyses showed significant differences in the comparisons of frail (standardized mean difference (SMD)—1.31, 95% confidence interval (CI) (−2.47, −0.15), p = 0.0271) and pre-frail (SMD—0.79, 95% CI (−1.58, −0.003), p = 0.0491) subjects vs. non-frail subjects. Sensitivity analyses reduced heterogeneity, resulting in a smaller but still highly significant between-groups difference. Results obtained indicate that lower 25(OH)D levels are significantly associated with increasing frailty severity. Future challenges include interventional studies testing the possible benefits of vitamin D supplementation in older adults to prevent/palliate frailty and its associated outcomes.


2000 ◽  
Vol 46 (8) ◽  
pp. 1065-1071 ◽  
Author(s):  
Steinar Hustad ◽  
Per Magne Ueland ◽  
Stein Emil Vollset ◽  
Ying Zhang ◽  
Anne Lise Bjørke-Monsen ◽  
...  

Abstract Background: Plasma total homocysteine (tHcy) is a risk factor for cardiovascular disease. tHcy concentrations are partly determined by folate, cobalamin, and vitamin B6 status, and methylenetetrahydrofolate reductase (MTHFR) and other flavoenzymes are important for the biotransformation of these vitamins. This motivates the investigation of the possible relationship between riboflavin status and tHcy. Methods: The study had a cross-sectional design and included 423 healthy blood donors, ages 19–69 years. We determined plasma tHcy, serum folate, serum cobalamin, serum creatinine, and MTHFR C677T genotype. In addition, we measured riboflavin and its two coenzyme forms, flavin mononucleotide and flavin adenine dinucleotide, in EDTA plasma by capillary electrophoresis and laser-induced fluorescence detection. Results: Riboflavin determined tHcy independently in a multiple linear regression model with adjustment for sex, age, folate, cobalamin, creatinine, and MTHFR genotype (P = 0.008). tHcy was 1.4 μmol/L higher in the lowest compared with the highest riboflavin quartile. The riboflavin-tHcy relationship was modified by genotype (P = 0.004) and was essentially confined to subjects with the C677T transition of the MTHFR gene. Conclusions: Plasma riboflavin is an independent determinant of plasma tHcy. Studies on deficient populations are needed to evaluate the utility of riboflavin supplementation in hyperhomocysteinemia.


2007 ◽  
Vol 293 (2) ◽  
pp. F594-F600 ◽  
Author(s):  
Victor Vitvitsky ◽  
Anna Prudova ◽  
Sally Stabler ◽  
Sanjana Dayal ◽  
Steven R. Lentz ◽  
...  

Elevated plasma total homocysteine (tHcy) is an independent risk factor for ischemic heart disease and stroke. Epidemiological studies reveal that men have higher tHcy levels than women, but the mechanism underlying this sex-dependent difference is unknown. One route for intracellular disposal of homocysteine is catalyzed by cystathionine β-synthase (CBS). Renal function is known to be an important determinant of tHcy, and, in this study, we demonstrate that renal CBS expression and activity in mice diminished approximately twofold after castration, whereas ovariectomization was without effect. The higher renal CBS activity in males (22.7 ± 3.1 mmol cystathionine·h−1·kg kidney−1) vs. females (8.4 ± 3.4 mmol cystathionine·h−1·kg kidney−1, P ≤ 10−6) in C57Bl/6J mice was associated with lower plasma tHcy levels in males vs. females, and this difference was exacerbated in Cbs+/− mice (7.7 ± 1.9 μmol/l in males vs. 13.8 ± 6.4 μmol/l in females, P = 0.005). Surprisingly, mammals exhibit a diversity of regulatory patterns for kidney CBS, with females exhibiting lower CBS activity in mice, higher in rats and humans, and being indistinguishable from males in rabbit, hamster, and guinea pig. Our data suggest that testosterone-dependent regulation of human CBS in kidney may contribute to sex-dependent differences in homocysteine transsulfuration.


2011 ◽  
Vol 81 (5) ◽  
pp. 328-334 ◽  
Author(s):  
Oya Halicioglu ◽  
Sezin Asik Akman ◽  
Sumer Sutcuoglu ◽  
Berna Atabay ◽  
Meral Turker ◽  
...  

Aim: Nutritional vitamin B12 deficiency in infants may occur because the maternal diet contains inadequate animal products. Clinical presentations of the infants who had nutritional vitamin B12 deficiency were analyzed in this study. Subjects and Methods: Patients with nutritional vitamin B12 deficiency were enrolled in the study between 2003 and 2010. The diagnosis was based on a nutritional history of mothers and infants, clinical findings, hematological evaluation, and low level of serum vitamin B12. Results: Thirty children aged 1 - 21 months constituted the study group. Poverty was the main cause of inadequate consumption of animal products of the mothers. All infants had predominantly breastfed. The most common symptoms were developmental delay, paleness, apathy, lethargy, anorexia, and failure to thrive. Hematological findings were megaloblastic anemia (83.3 %), thrombocytopenia (30 %), and severe anemia (13.3 %). All of the mothers had low serum B12 levels; eight of them had megaloblastic anemia. Conclusion: The unusual clinical manifestations of vitamin B12 deficiency may also be seen apart from neurological and hematological findings. Nutritional vitamin B12 deficiency due to maternal deficiency might be a serious health problem in infants. Therefore, screening and supplementation of pregnant and lactating women to prevent infantile vitamin B12 deficiency should be considered.


2020 ◽  
Vol 90 (5-6) ◽  
pp. 535-552 ◽  
Author(s):  
Mahdieh Abbasalizad Farhangi ◽  
Mahdi Vajdi

Abstract. Backgrounds: Central obesity, as a pivotal component of metabolic syndrome is associated with numerous co-morbidities. Dietary factors influence central obesity by increased inflammatory status. However, recent studies didn’t evaluate the association between central obesity and dietary inflammation index (DII®) that give score to dietary factors according to their inflammatory potential. In the current systematic review and meta-analysis, we summarized the studies that investigated the association between DII® with central obesity indices in the general populations. Methods: In a systematic search from PubMed, SCOPUS, Web of Sciences and Cochrane electronic databases, we collected relevant studies written in English and published until 30 October 2019. The population of included studies were apparently healthy subjects or individuals with obesity or obesity-related diseases. Observational studies that evaluated the association between DII® and indices of central obesity including WC or WHR were included. Results: Totally thirty-two studies were included; thirty studies were cross-sectional and two were cohort studies with 103071 participants. Meta-analysis of observational studies showed that higher DII® scores were associated with 1.81 cm increase in WC (Pooled weighted mean difference (WMD) = 1.813; CI: 0.785–2.841; p = 0.001). Also, a non-significant increase in the odds of having higher WC (OR = 1.162; CI: 0.95–1.43; p = 0.154) in the highest DII category was also observed. In subgroup analysis, the continent, dietary assessment tool and gender were the heterogeneity sources. Conclusion: The findings proposed that adherence to diets with high DII® scores was associated with increased WC. Further studies with interventional designs are necessary to elucidate the causality inference between DII® and central obesity indices.


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