In this third up date of the Cochrane review , there were no differences in effects of homocysteine-lowering interventions in the form of supplements of vitamins B6 , B9 or B12 given alone or in combination comparing with placebo on myocardial infa rct ion , death from any cause or adverse events .
BACKGROUND Cardiovascular disease , which includes coronary artery disease , stroke and peripheral vascular disease , is a leading cause of death worldwide .
Homocysteine is an amino acid with biological functions in methionine metabolism .
A postulated risk factor for cardiovascular disease is an elevated circulating total homocysteine level .
The impact of homocysteine-lowering interventions , given to patients in the form of vitamins B6 , B9 or B12 supplements , on cardiovascular events has been investigated .
This is an up date of a review previously published in 2009 , 2013 , and 2015 .
OBJECTIVES To determine whether homocysteine-lowering interventions , provided to patients with and without pre-existing cardiovascular disease are effective in preventing cardiovascular events , as well as reducing all-cause mortality , and to evaluate their safety .
National Institutes of Health State-of-the-Science Conference Statement: Multivitamin/Mineral Supplements and Chronic Disease Prevention
National Institutes of Health ( NIH ) consensus and state-of-the-science statements are prepared by independent panels of health professionals and public representatives on the basis of 1 ) the results of a systematic literature review prepared under contract with the Agency for Healthcare Research and Quality ( AHRQ ) , 2 ) presentations by investigators working in areas relevant to the conference questions during a 2-day public session , 3 ) questions and statements from conference attendees during open discussion periods that are part of the public session , and 4 ) closed deliberations by the panel during the remainder of the second day and the morning of the third . This statement is an independent report of the panel and is not a policy statement of the NIH or the federal government . The statement reflects the panel 's assessment of medical knowledge available at the time the statement was written . Thus , it provides a snapshot in time of the state of knowledge on the conference topic . When reading the statement , keep in mind that new knowledge is inevitably accumulating through medical research . At least half of American adults take a dietary supplement , the majority of which are multivitamin/multimineral ( MVM ) supplements . As more and more Americans seek strategies for maintaining good health and preventing disease , and as the marketplace offers an increasing number of products to fulfill that desire , it is important that consumers have the best possible information to make their choices . Assessing the available scientific evidence on the benefits of MVM supplement use for chronic disease prevention , identifying the gaps in the evidence , and recommending an appropriate research agenda to meet the shortfalls are subjects considered in this report . The word vitamine was coined in 1912 , as an abbreviated term meant to capture the notion of important factors in the diet , or vital amines . This was preceded more than 150 years earlier by British navy physician James Lind 's discoveryin the first recorded controlled trialthat citrus juice , a good source of what was found 2 centuries later to be vitamin C , could prevent scurvy in sailors . In 1913 , the first vitamin was isolated : thiamin , the deficiency of which caused beriberi . Thirteen vitamins and 15 essential minerals have now been identified as important to human nutrition . Large-scale fortification of diets began in the United States with the addition of iodine to table salt in 1924 to prevent goiter , followed by the addition of vitamin D to milk in 1933 to prevent rickets and the addition of thiamin , riboflavin , niacin , and iron to flour in 1941 . Multivitamin/multimineral products providing more than vitamins A and D became available in pharmacies and grocery stores in the mid-1930s . In the early 1940s , the first MVM tablet was introduced . Although clinical deficiency of vitamins or minerals , other than iron , is now uncommon in the United States , growth in supplement use has accelerated rapidly with marketing spurred by cl aims some based on scientific studies that chronic conditions could be prevented or treated by supplement use . Annual sales of supplements to Americans are now reported at about $ 23 billion , a substantial share of which is spent on vitamins and minerals . Because of such widespread use of MVM , increasing public and medical confusion over apparently contradictory results from studies , and reports of possible adverse effects from overuse in certain circumstances , the Office of Dietary Supplements and the Office of Medical Applications of Research of the NIH convened a State-of-the-Science Conference on Multivitamin/Mineral Supplements and Chronic Disease Prevention , held on 1517 May 2006 , in Bethesda , Maryl and . The goal of the conference was to assess the evidence available on MVM use and outcomes for chronic disease prevention in the generally healthy population of adults and to make recommendations for future research . The conference focused on vitamins and minerals and did not deal with botanicals , hormones , or other supplements . It also did not address the treatment of vitamin or mineral deficiencies . Except for considerations of safety , the conference also did not review issues of primary relevance to pregnant women or children . Specifically , the conference explored the following key questions : 1 ) What are the current patterns and prevalence of the public 's use of MVM supplements ? 2 ) What is known about the dietary nutrient intake of MVM users versus nonusers ? 3 ) What is the efficacy of single vitamin/mineral supplement use in chronic disease prevention ? 4 ) What is the efficacy of MVM  in chronic disease prevention in the general population of adults ? 5 ) What is known about the safety of MVM  for the generally healthy population ? and 6 ) What are the major knowledge gaps and research opportunities regarding MVM use ? During the first 2 days of the conference , experts presented information on each of the key questions . After weighing the scientific evidence , including the data presented by the speakers and a formal evidence report commissioned through AHRQ , an independent panel prepared and presented a draft of this state-of-the-science statement addressing the conference questions . The evidence report prepared for the conference is available at www.ahrq.gov/clinic/tp/multivittp.htm . For the purpose of this statement , the term MVM refers to any supplement containing 3 or more vitamins and minerals but no herbs , hormones , or drugs , with each component at a dose less than the tolerable upper level determined by the Food and Nutrition Boardthe maximum daily intake likely to pose no risk for adverse health effects . Our review also included studies of the relationship of single-nutrient supplements and 2-nutrient supplements to certain disease outcomes . The term primary prevention refers to preventing the development of disease in a person who does not have the disease in question . The chronic conditions assessed include cancer ; age-related sensory loss ; and cardiovascular , endocrine , neurologic , musculoskeletal , gastroenterologic , renal , and pulmonary diseases . A word is warranted about the nature of the evidence base considered by the panel . The range of vitamins and minerals of possible interest was so broad that the conference planning committee chose to focus the evidence report on nutrients for which the potential for impact had been most strongly suggested and on conditions for which supplements were thought to have the most potential influence . The planning committee also limited the scope of the evidence report to consideration of r and omized , controlled trials ( RCTs ) , which are generally considered the gold st and ard for evidence -based decision making . These are studies in which participants are allocated by chance alone to receive or not to receive 1 of 2 or more clinical interventions . For example , while folate supplementation was initially shown to decrease the risk for neural tube defects in animal studies , outcome data in nonhuman models were not considered sufficient evidence on which to base policy recommendations . At the next level of evidence , observational studies in humans suggested efficacy of folate supplementation to prevent such defects . However , these were criticized because they were not r and omized and were potentially subject to bias . Not until these findings were confirmed by RCTs in humans was public policy implemented , including fortification of cereal grains with folate . An observational study is one in which the exposure or treatment of interest is not assigned to the participant by the investigator . Such studies suggested that -carotene intake might protect against the development of some types of cancer . However , RCTs of -carotene supplementation not only showed no benefit , they also found an increased risk for lung cancer in persons who smoked cigarettes or who were exposed to asbestos . These examples illustrate both the risk of relying only on observational studies and the advantage of RCTs in identifying both benefits and risks of MVM supplementation . Limiting the focus of our statement to RCTs has some inherent limitations , given the potential of other types of studies to provide important insights . Observational studies , for example , are particularly useful for generating hypotheses , defining adverse effects , and documenting long-term treatment consequences . They are often essential precursors to the well-conducted RCTs important for policy formation . Our principal recommendations focus on the compelling research activities that must be supported to better inform the decisions that millions of Americans are making each day to use or not to use MVM supplements to prevent chronic disease . At the same time , mindful of the constraints of the available evidence base , we have also taken care not to make premature recommendations about whether generally healthy Americans should or should not take MVM supplements . Because of the need for more reliable information on MVMs , we have made strong recommendations for research and for increased U.S. Food and Drug Administration ( FDA ) oversight of the MVM industry . 1 . What Are the Current Patterns and Prevalence of the Public 's Use of MVM Supplements ? More than half of American adults take dietary supplements in the belief that they will make them feel better , give them greater energy , improve their health , and prevent and treat disease . The use of supplements has been steadily increasing , and growth appears likely to continue . Currently , users spend more than $ 23 billion per year on supplements , and among this supplement-using population , MVM is the major category of supplements , used by about one third of Americans . Uncertainty remains in estimating prevalence of use because of problems defining these products ; increasing complexity in the formulation of supplements , including more non-MVM components and specialized formulas ; and varying frequency of use . It appears that use is higher
In this third up date of the Cochrane review , there were no differences in effects of homocysteine-lowering interventions in the form of supplements of vitamins B6 , B9 or B12 given alone or in combination comparing with placebo on myocardial infa rct ion , death from any cause or adverse events .
BACKGROUND Cardiovascular disease , which includes coronary artery disease , stroke and peripheral vascular disease , is a leading cause of death worldwide .
Homocysteine is an amino acid with biological functions in methionine metabolism .
A postulated risk factor for cardiovascular disease is an elevated circulating total homocysteine level .
The impact of homocysteine-lowering interventions , given to patients in the form of vitamins B6 , B9 or B12 supplements , on cardiovascular events has been investigated .
This is an up date of a review previously published in 2009 , 2013 , and 2015 .
OBJECTIVES To determine whether homocysteine-lowering interventions , provided to patients with and without pre-existing cardiovascular disease are effective in preventing cardiovascular events , as well as reducing all-cause mortality , and to evaluate their safety .