Results of a pilot study to provide evidence on the efficacy of vitamin B12 to normalise elevated homocysteine of vegetarians

Homocysteine can be remethylated through the major folic cycle path. It is recycled to methionine in a reaction catalyzed by the enzyme methionine synthase and is absolutely dependent on the essential vitamin B12 methylcobalamin (MeCbl). All other forms of vitamin B12 must be converted to MeCbl prior to their usage. This can prove to be problematic, particularly for the aged. Vegetarians are known to be susceptible to vitamin B12 deficiency, due to a lack of dietary animal produce, which can elevate plasma total homocysteine (tHcy). There is positive evidence that links elevated plasma (tHcy) with cardiovascular disease (CVD). The specific objective of the present study was to establish if supplementary MeCbl will optimise elevated levels of plasma tHcy of vitamin B12 deficient vegetarians

Efficacy of methylcobalam in to normalise elevated homocysteine of vitamin B12 deficient vegetarians: a double blind placebo control study

Vegetarians are known to be deficient in vitamin B12, due to a lack of dietary animal products,which can elevate plasma total homocysteine (tHcy). Elevated total tHcy can render vegetarians susceptible to cardiovascular disease (CVD).There are a limited number of published studies in relation to the efficacy of methylcobalamin to normalise plasma tHcy of vitamin B12 deficient vegetarians.The primary objective of the present study was to explore the relationship between supplementary oral methylcobalamin and levels of tHcy of vitamin B12 deficient vegetarians; to reduce the risk of developing primary CVD. A randomised double blind placebo controlled pilot study was conducted to monitor and analyse baseline and post treatment levels of plasma tHcy, 49 volunteer vegetarians were recruited to participate in this study. Statistical analysis employing SPSS software indicated that methylcobalamin reduced mean baseline plasma tHcy of 15.5 μmolL-1 (n=39) to a mean plasma tHcy level of 8.4 μmolL-1 (P < 0.001). In a second group that contained details of ten withdrawn participants, which was conducted on an ‘Intention to Treat’ (ITT) basis, indicated that methylcobalamin was shown to be reduced from a mean baseline plasma tHcy of 14.7 μmolL-1(n=49)to a mean plasma tHcy level of 9.1 μmolL-1 (P < 0.001).The findings of the study have the potential to alert vegetarians of the possible risk of becoming vitamin B12 deficient, and to help avoid the risk of developing homocysteine related CVD. The quality data obtained in the study will allow an accurate sample size to be calculated for a future definite clinical study

An investigation into the pragmatic diets of vegetarianism: the results of a pilot study

Published recommended various classifications of vegetarian diets are widespread across the globe, but few published articles if any report on the types of foods actually consumed by vegetarians in general. The primary objective was to elucidate this aspect of vegetarianism, analysis of food consumption over a fourteen day period, with respect to the various manifestations of vegetarianism, was undertaken in the form of a pilot study to indicate the contents of these diets as compared with recommended daily allowances (RDA) and adequate intake (AI) values. Five lactovegetarians, twenty lactoovovegetarians and fourteen vegans, were recruited. The study included a detailed analysis of the vegetarian participants’ diet, through the compilation of an individual diet diary. Statistical analysis employing Microsoft Excel software was conducted to determine the outcome of the vegetarians’ diets, with each mean nutrient and mean dietary energy value compared against RDA and AI. Analysis of the participants’ diet diaries indicated somewhat unexpectedly a failure to meet the RDA and AI for several important nutrients. Furthermore, the daily metabolizable energy level for all classifications of vegetarians was lower than the recommended AI for daily energy requirements. Whilst it is generally accepted that vegetarianism can lead to a healthy lifestyle, the findings of this research indicate that vegetarianism participants may be at risk of deficiency of certain nutrients that could potentially lead to chronic medical conditions. The statistical findings obtained in the study will allow an accurate sample size to be calculated for each important item for future large definitive studies

Efficacy of methylcobalamin to normalise elevated homocysteine of vitamin B12 deficient vegetarians: a double blind placebo control study

Vegetarians are known to be deficient in vitamin B12, due to a lack of dietary animal products, which can elevate plasma total homocysteine (tHcy). Elevated total tHcy can render vegetarians susceptible to cardiovascular disease (CVD). There are a limited number of published studies in relation to the efficacy of methylcobalamin to normalise plasma tHcy of vitamin B12 deficient vegetarians. The primary objective of the present study was to explore the relationship between supplementary oral methylcobalamin and levels of tHcy of vitamin B12 deficient vegetarians; to reduce the risk of developing primary CVD. A randomised double blind placebo controlled pilot study was conducted to monitor and analyse baseline and post treatment levels of plasma tHcy, 49 volunteer vegetarians were recruited to participate in this study. Statistical analysis employing SPSS software indicated that methylcobalamin reduced mean baseline plasma tHcy of 15.5 µmolL-1 (n=39) to a mean plasma tHcy level of 8.4 µmolL-1 (P < 0.001). In a second group that contained details of ten withdrawn participants, which was conducted on an ‘Intention to Treat’ (ITT) basis, indicated that methylcobalamin was shown to be reduced from a mean baseline plasma tHcy of 14.7 µmolL-1(n=49) to a mean plasma tHcy level of 9.1 µmolL-1 (P < 0.001). The findings of the study have the potential to alert vegetarians of the possible risk of becoming vitamin B12 deficient, and to help avoid the risk of developing homocysteine related CVD. The quality data obtained in the study will allow an accurate sample size to be calculated for a future definite clinical study

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

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 B12 can elevate homocysteine. Vegetarians are a group of the population who are potentially at greater risk of vitamin B12 deficiency than omnivores. This is the first systematic review and meta-analysis to appraise a range of studies that compared the homocysteine and vitamin B12 levels 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 B12 of 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 B12 did 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 B12 is animal products and those who choose to omit or restrict these products are destined to become vitamin B12 deficient. 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

Plasma Total Homocysteine and its Relationship with Cardiovascular Disease

Aims: The specific aim of this review was to compile the first systematic review of systematic reviews and meta-analyses from a range of studies that evaluates the evidence that elevated homocysteine may be a risk factor for CVD. Data Synthesis: 379 entries were identified by initial screening using set criteria revealing eleven meta-analyses, one systematic review, two systematic reviews/meta-analyses and ten other studies, between 1994 and 2013.These studies compared homocysteine levels and its relationship with twelve different types of CVD chronic conditions. Final methodological quality assessment was conducted independently using the instrument AMSTAR for the systematic reviews and meta-analyses. The remaining studies were assessed using data extraction tools from JBI QARI, Appendix 2 &amp; 4 packages. Conclusions: From the selected studies, 82.8% of the CVD conditions demonstrated that epidemiologic and clinical data strongly indicated that elevated homocysteine levels is a risk factor for primary CVD. 71.4% of the CVD conditions demonstrated that plasma tHcy can be employed as an independent biomarker. Despite 46.2% of the CVD conditions finding that reducing plasma tHcy lowers the risk of many CVD events, it remains unclear whether the reduction in plasma tHcy will reduce the risk of some CVD events; it is therefore considered prudent to take precautionary measures to aim for normal levels of homocysteine to avoid the risk of developing or exacerbating CVD. Moreover, it was shown that levels of homocysteine can be profoundly affected by diet, supplementation and lifestyle. The present study will help to clarify the present scientific understanding of this subject

Plasma total homocysteine and its relationship with cardiovascular disease

Aims: The specific aim of this review was to compile the first systematic review of systematic reviews and meta-analyses from a range of studies that evaluates the evidence that elevated homocysteine may be a risk factor for CVD. Data Synthesis: 379 entries were identified by initial screening using set criteria revealing eleven meta-analyses, one systematic review, two systematic reviews/meta-analyses and ten other studies, between 1994 and 2013.These studies compared homocysteine levels and its relationship with twelve different types of CVD chronic conditions. Final methodological quality assessment was conducted independently using the instrument AMSTAR for the systematic reviews and meta-analyses. The remaining studies were assessed using data extraction tools from JBI QARI, Appendix 2 & 4 packages. Conclusions: From the selected studies, 82.8% of the CVD conditions demonstrated that epidemiologic and clinical data strongly indicated that elevated homocysteine levels is a risk factor for primary CVD. 71.4% of the CVD conditions demonstrated that plasma tHcy can be employed as an independent biomarker. Despite 46.2% of the CVD conditions finding that reducing plasma tHcy lowers the risk of many CVD events, it remains unclear whether the reduction in plasma tHcy will reduce the risk of some CVD events; it is therefore considered prudent to take precautionary measures to aim for normal levels of homocysteine to avoid the risk of developing or exacerbating CVD. Moreover, it was shown that levels of homocysteine can be profoundly affected by diet, supplementation and lifestyle. The present study will help to clarify the present scientific understanding of this subject