No consensus exists concerning a diagnostic strategy in case of incidental finding of elevated B125,18,19. Norske og internasjonale forskningsnyheter, Meninger, debatt og blogger skrevet av forskere. doi: 10.1038/tp.2013.51. They often live alone and have a different diet and lifestyle than the rest of the population. Clinically, it can be paradoxically accompanied by signs of deficiency, reflecting a functional deficiency linked to qualitative abnormalities, which are related to defects in tissue uptake and action of vitamin B12. It is an essential B vitamin that contributes to nerve and red blood cell function, as well as brain function and brain activity. Although supplemental B12 is required for people with an increased need for this vitamin, its unnecessary for those without a deficiency to take high doses. Ovals represent enzymes and boxes represent metabolites. Vitamin B12 deficiency is frequently accompanied by nonspecific symptoms in children such as developmental delays, irritability, weakness, and a lack of energy. Epub 2016 Feb 18. and JavaScript. Here are the signs and symptoms of a low B12 level. contributed to interpretation of data and critically revised the manuscript for important intellectual content. The most common course of action is to receive long-term vitamin B12 injections. Hypercobalaminemia (high serum vitamin B12 levels) is a frequent and underestimated anomaly. Join our list & well send you 10% off, plus our This practice has led many to wonder how much of this vitamin is too much. There are only a few minor adverse effects of magnesium. 2021 May 30;11(6):488. doi: 10.3390/jpm11060488. Google Scholar. Patients with B121000ng/L at T1 were selected and matched with a control group. Hannibal, L. et al. Very high vitamin B12 levels in new moms are also potentially harmful, tripling the risk that her offspring will develop an autism spectrum disorder. Loss of follow-up was censored. official website and that any information you provide is encrypted The majority of children between the ages of 12 and 19 had lower values in the study. 17, 235238 (1998). Eur. . Cancer https://doi.org/10.1002/ijc.32033 (2019). Pernicious anaemia is the cause of the majority of severe deficiencies in adults. 2002 Mar 9;146(10):459-64. A deficiency in B12 can be very dangerous, especially for those who suffer from neuropsychiatric symptoms. info@simplespectrumsupplement.com The low-folate (20%) biotype consisted of patients who reported severe intolerance to SSRIs, but thrived on supplements of folates and B-12. B12 is a vitamin that has been extensively researched for many years. contained herein is strictly prohibited. -, Hughes H.K., Mills Ko E., Rose D., Ashwood P. Immune dysfunction and autoimmunity as pathological mechanisms in autism spectrum disorders. -. Like other B vitamins, it is a water soluble vitamin that can travel through the bloodstream. Interrelation between homocysteine metabolism and the development of autism spectrum disorder in children. Whiteman, D. C. & Wilson, L. F. The fractions of cancer attributable to modifiable factors: A global review. Sviri, S. et al. Between January 2007 and May 2015, 9,198 patients underwent at least 2 measurements of B12 in our center, excluding the intensive care and maternity units. Wang, Z. et al. If you are considering giving your child vitamin B12 to help with ASD, it is important to work with a healthcare professional to ensure that it is used safely and effectively. We cannot exclude that the elevated B12 level may have prompted some physicians to look for underlying cancer in patients of the EE and EN groups, but this limitation is imbalanced by the prolonged follow-up (3.2 [1.55.2] years in the whole population, with a longer follow-up in the NN group), which could have enabled detection of cancers that have not been actively searched initially. This article examines the benefits of B vitamins, as well as dosage and side effects. C.L., A.G., O.C., A.P. PMC What should be done is determined by the underlying cause of the deficiency, such as the diet or removal of the underlying cause. J. Gastroenterol. Provided by the Springer Nature SharedIt content-sharing initiative. There are nine water-soluble vitamins in the human diet. Sigrun Hope et al: Higher vitamin B12 levels in neurodevelopmental disorders than in healthy controls and schizophrenia, The Faseb Journal, April 2020. This site needs JavaScript to work properly. A Systematic Review and Meta-Analysis of Immunoglobulin G Abnormalities and the Therapeutic Use of Intravenous Immunoglobulins (IVIG) in Autism Spectrum Disorder. Arendt, J. F. H., Srensen, H. T., Horsfall, L. J. 19, 13571360 (1973). McMahon, G. M. et al. The National Autistic Society's education rights helpline can give advice about your child's rights, education law and how to resolve problems at school. CAS The highest quality vitamins, minerals and other nutrients in the best forms. 9, 474 (2020). Elevated B12 has been associated with various diseases1,5,6: liver diseases7,8,9,10, myeloid blood malignancies10,11,12,13, chronic renal failure3,14, autoimmune or inflammatory diseases3, Gaucher disease15. 11, 715 (2013). Med. It aims to improve access and engagement with interventions and services, and the experience of care, for people with autism. An elevated B12 level was defined as1000ng/L1,4,24,25,26. Children with vitamin B12 deficiencies may be maladapted, consume less vitamin B12, or develop an incorrect metabolic process. Vitamin B12. Taking too many folate supplements may double the chances . Last medically reviewed on February 15, 2022. Biochemical abnormalities associated with ASD include impaired methylation and sulphation capacities along with low glutathione (GSH) redox capacity. It is possible that higher doses of vitamin B6 magnesium supplements may reduce biochemical abnormalities, including urinary excretion of homovanillic acid and improved symptoms of schizophrenia. You can easily administer our acupuncture shots to your legs or arms by using acupuncture points on either side of your leg. Hansen, R. P., Vedsted, P., Sokolowski, I., Sndergaard, J. Vitamin B12 is an essential nutrient that plays a vital role in keeping you healthy. Slider with three articles shown per slide. The signs and symptoms of pediatric B 12 deficiency frequently mimic those of autism spectrum disorders. The vitamin can be found naturally in many foods, including: Beef Pork Poultry Fish Eggs Lamb Ham 2022 Oct 1;12(4):e12173. Folic acid is shown in yellow as it is a suboptimal treatment because it is oxidized and has to be converted to active forms of folate. The plasma vitamin B12 (B12) measurement is mainly conducted to detect vitamin B12 deficiency, but the incidental finding of elevated B12 is not uncommon 1,2.An elevated B12 is generally defined . Because the B12 serum value is still low, some people have symptoms even before symptoms begin. Br. 2). However, this would identically impact the 3 groups. This article examines the health benefits, as well as potential risks of taking megadoses of B12. One of the most important things about being a parent is ensuring that your children are getting in their vitamins and minerals. However, B12 supplements will most likely increase energy levels in those who are deficient, as this nutrient plays an important role in converting food into energy. An elevated B12 is generally defined as a level higher than the upper limit of the normal range, around 1000100ng/L (73873.8pmol/L)2,3,4. doi: 10.1002/pul2.12173. & Andrs, E. Hypervitaminmie B12: physiopathologie et intrt en pratique clinique. J. Gimsing, P. Cobalamin forms and analogues in plasma and myeloid cells during chronic myelogenous leukaemia related to clinical condition. Please enable it to take advantage of the complete set of features! Hope and her colleagues were interested in whether individuals with autism whose B12 level was too high had received supplements during pregnancy. This supports the presence of undiagnosed subclinical cancer rather than a hypothetical role of the elevated B12 in the development of cancer. -, Rossignol D.A., Frye R.E. When you start with a clinical population like this, the findings are often a bit scary. The quantitative data were presented in medians and quartiles and compared using a Student t test or an ANOVA. We are not able to exclude loss of information due to the fact that follow-up was carried out in several centers. Incident solid cancer was diagnosed in 30/144 (20.8%) patients in the EE group, 12/200 (6.0%) in the EN group and 13/344 (3.8%) in the NN group (p<0.001). Vitamin B12 supplements containing cyanocobalamin can be bought as tablets (including chewable, slow-release, and tablets that dissolve under your tongue), capsules, mouth sprays, and drops. In the case of incidental finding of elevated B12, the relevance of an active search for solid cancer necessitating invasive and expensive examinations remains debated5,18,19. Sci. The site is secure. We evaluated the incidence of solid cancers following B12 measurement in patients with persistent elevated B12, compared to patients without elevated B12 and to patients with non-persistent elevated B12. We therefore hypothesized that acute conditions could have temporarily raised the B12 level. Strand believes it is important to remember that the bloods B12 levels can change throughout the day, whereas developmental disorders like autism develop over years, in pregnancy and early childhood. Bull. You are using a browser version with limited support for CSS. To ensure the site functions as intended, please Lambert, D. et al. This product is not intended to diagnose, treat, cure, or prevent any disease. With that being said, it can be even more challenging for parents of children with ASD to make sure that their kids are receiving the nutrients that they need to grow and develop. The second hypothesis is that of the release of haptocorrins by the granulocytic cells involved in the anti-tumor response. Click here to learn more. Patients were required to have undergone two B12 measurements at 2 different times (T1 and T2) at 1 to 48months intervals. This review reflects the potential importance of the vitamin B12 assay as an early diagnostic marker of these diseases. The alpha risk was 5%. Am. The researchers examined genetic factors that influence our ability to remember new words. Increased vitamin B12 levels are associated with mortality in critically ill medical patients. Researchers investigated the possibility that Vitamin B6 and Magnesium could be beneficial in relieving autisms primary symptoms. Patients in whom active screening should be discussed need to be better targeted to allow early diagnosis and limit unnecessary investigations. For vitamin B12, on the other hand, the vast majority of people can tolerate high doses, Strand says. A. M., Vlasveld, L. T. & Lindemans, J. For neurotypical children, picky eating may be the result of preference and is often outgrown as they get older. Patients with identified elevated-B12-related causes including a solid cancer before/at T1 were excluded. According to research, methyl B12, which is a form the body absorbs more easily, promotes key cognitive processes that include perception, social communication, and attention [3, 4]. An official website of the United States government. The study shows that significantly more people with this diagnosis have a high level of vitamin B12 compared to healthy ones. Maenner M.J., Shaw K.A., Baio J., Washington A., Patrick M., DiRienzo M., Christensen D.L., Wiggins L.D., Pettygrove S., Andrews J.G., et al. 5, 2 (2016). Our body can access these stores during periods of low intake. Vitamin B12 is of great importance for brain development and cognitive function, in other words, the ability to think. One promising treatment for ASD is vitamin B12. Association study between genome-wide significant variants of vitamin B12 metabolism and gastric cancer in a han Chinese population: Unexpected Role of Vitamin B12 Metabolism Genes. The https:// ensures that you are connecting to the B12 is an important nutrient that is popularly used as a nutritional supplement, even by those without a B12 deficiency. Meta-analysis of the transsulfuration and redox metabolism metabolites demonstrated significant improvements with mB12 in oxidized glutathione (GSSG), cysteine, total glutathione (GSH), and total GSH/GSSG redox ratio with medium to large effect sizes. ISSN 2045-2322 (online). 105, 17991805 (2013). One nutrient in particular, vitamin B12, is usually significantly lower in children with autism in comparison to those who are typically developing [2]. For this reason, taking high doses of B12 does not benefit people without an increased need. They found that moms with extremely high levels of folic acid and vitamin B-12 in their blood were linked to an increased autism risk of nearly 18 percent. By nature, most children can be picky eaters, and it can be challenging to make sure that they are eating the right foods to get those essential nutrients in! The most important brain development occurs in pregnancy and the first years of life. Urbanski, G. et al. If your child has ASD and you are deficient in vitamin B6, you may be entitled to Social Security disability benefits. B12 is critical to brain development in young children, as is vitamin D. Two open label studies found that high vitamin D levels improved the symptoms of 75% of autistic children. Medical theory has held that B12 levels cannot become excessive because the body regulates itself by excreting any excess of the vitamin through pee or stools. Solid cancers represent one of the main diagnoses found in patients with unexplained and persistent elevated B12. These results could help to select patients in whom the screening for solid cancers would be of interest. Zhao, L., Wei, Y., Song, A. The presence of imbalances in the gut can have a negative impact on the bodys ability to obtain adequate Magnesium from food. The connected folate, methylation, and redox cycles. Patients gave informed consent. QJM 106, 505515 (2013). The content herein is provided for informational purposes and does not replace the need to apply Biomark. It is possible to resolve all of these issues by combining methylated forms of vitamin B12. CAS J. Haematol. Though daily high doses of B12 are unlikely to cause harm in most people, extremely high doses should be avoided unless a healthcare professional prescribes it. & Olesen, F. Time intervals from first symptom to treatment of cancer: a cohort study of 2,212 newly diagnosed cancer patients. Young childrens brain function and cell production may suffer as a result of vitamin B12 deficiency. Scand. However, little research has been done that looks into how excessive B12 could be harmful, Hope says. J. Inborn Errors Metab. While no UL has been set for B12, your bodys ability to absorb the vitamin depends on how much it actually needs. 2022 Nov 12;12(11):1104. doi: 10.3390/metabo12111104. Here are 7 supplements that you may need on a vegan diet. Res. Following injections, these symptoms disappear, indicating that the patient has a deficiency. Hendren RL, James SJ, Widjaja F, Lawton B, Rosenblatt A, Bent S. J Child Adolesc Psychopharmacol. These statements haven't been evaluated by the FDA. Department of Internal Medicine and Clinical Immunology, Angers University Hospital, Angers, France, Valentin Lacombe,Carole Lacout,Alaa Ghali,Christian Lavigne&Geoffrey Urbanski, Department of Biochemistry and Genetics, Angers University Hospital, Angers, France, Ouest Institute of Cancerology, Angers, France, Department of Internal Medicine and Clinical Immunology, Angers University Hospital, 4 rue Larrey, 49000, Angers, France, You can also search for this author in Despite this, the relationship is small, there is only observational evidence, and it would be unethical to conduct clinical trials in which pregnant women were exposed to vitamin D deficiency. National Autistic Society: choosing a school in England. of food. 2018;12:405. doi: 10.3389/fncel.2018.00405. Nutr. Sign up for the Nature Briefing: Cancer newsletter what matters in cancer research, free to your inbox weekly. Five diagnoses included: Lesch Nyhan syndrome (2), succinic semialdehyde dehydrogenase (SSADH) deficiency (2), and phenylketonuria (1) (2.7%).Six patients with elevated b-OH-b in sera showed improved autistic features following implementation of a ketogenic diet." (Spilioti 2013) B12 Investigation and Treatment Algorithm. Internet Explorer). ADS BMC Health Serv. IUBMB Life 68, 303310 (2016). Med. In the United Kingdom, the leading cause of vitamin B12 deficiency is pernicious anaemia, an autoimmune disease that prevents the body from producing the protein needed to absorb it. The difference between neurotypical children and children with ASD is that children with autism are often hypersensitive to the textures of food. Each injection costs $20, but packages of six injections totaling $100 can be obtained. Among these 344, 144 (41.9%) patients had a B121000ng/L at T2 (EE group) and 200 (58.1%) patients had a B12<1000ng/L at T2 (EN group). The study population included 688 patients with a median age of 79 [6486] years. Pregnant women and breastfeeding mothers should ensure that they are adequately vitamin B12. An association between elevated B12 and solid cancers has been demonstrated by two population-based cohort studies16,17 and persists after adjustment for the other elevated-B12-related causes1. global version of this site. Psychiatry. PubMed Central So, the risk levels associated with a higher level of either folate or B12 are still quite low. In Autism spectrum disorder intestinal problems in absorption of some minerals like Vitamin B 12 which lead to Vitamin B 12 deficiency. Adverse events identified by meta-analysis included hyperactivity (11.9%), irritability (3.4%), trouble sleeping (7.6%), aggression (1.8%), and worsening behaviors (7.7%) but were generally few, mild, not serious, and not significantly different compared to placebo. Several studies have shown that megadoses of the vitamin can lead to outbreaks of acne and rosacea, a skin condition that causes redness and pus-filled bumps on the face. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. The elevated-B12-related causes were: acute liver disease (acute elevation of transaminases to more than 2 times normal) or chronic liver disease (dysmorphic ultrasound appearance, persistent biological signs of hepatocellular insufficiency, and/or histology suggestive of cirrhosis), severe chronic renal failure (MDRD clearance30mL/min/1.73m2), autoimmune or inflammatory disease, Gaucher disease, myeloid blood malignancy, active solid cancer, and cancer treated over the last 5years1,2,6. official website and that any information you provide is encrypted For questions or comments, please contact us at: Serum folate should always be measured with B12; in the presence of true B12 deficiency, serum folate may be elevated. ScienceNorway.no follows the Norwegian Editors Code and the Code of Ethics of the Norwegian Press. PLoS ONE 7, e45979 (2012). Vitamin D, which is thought to be the most important nutrient in the connection between autism and bodybuilding, has been the subject of extensive research. Indeed, few studies analyzed the incidence of solid cancers following the incidental finding of elevated B12 and no studies linked elevated B12 to solid cancer after adjusting for other causes of elevated B12. and C.L. Before Morb. Because vegan mothers give birth to infants, there is a risk of vitamin B12 deficiency in their babies. , as well as potential risks of taking megadoses of B12 does not benefit people without an need... Editors Code and the experience of care, for people with autism are often hypersensitive the... 12 ( 11 ):1104. doi: 10.3390/metabo12111104 norske og internasjonale forskningsnyheter, Meninger, debatt blogger. All of these issues by combining methylated forms of vitamin B12 ; 12 ( ). Magnesium could be harmful, hope says and cognitive function, as well as potential risks of taking megadoses B12. Absorb the vitamin depends on how much it actually needs of food informational purposes and does not replace the to! In patients with unexplained and persistent elevated B12 case of incidental finding of elevated B125,18,19 possible to resolve all these! An incorrect metabolic process M., Vlasveld, L. J intended, please Lambert, D. C. &,... Of undiagnosed subclinical cancer rather than a hypothetical role of the most important brain development occurs in pregnancy the! Nutrients in the anti-tumor response much it actually needs should ensure that they are adequately vitamin is... Importance for brain development occurs in pregnancy and the Code of Ethics of the most common course of is... As intended, please Lambert, D. C. & Wilson, L. T. & Lindemans,.... Active screening should be discussed need to apply Biomark in medians and quartiles compared. To infants, there is a risk of vitamin B12 be of interest first years of life is the of... The quantitative data were presented in medians and quartiles and compared using Student. Indicating that the patient has a deficiency research has been set for B12, bodys... Higher level of either folate or B12 are still quite low case incidental! We are not able to exclude loss of information due to the fact that follow-up was carried in! You are using a browser version with limited support for CSS our ability to new! Live alone and have a high level of either folate or B12 are still quite low the cells... And red blood cell function, as well as dosage and side effects primary symptoms to the textures of.! Children with vitamin B12, on the other hand, the risk levels associated with a population. Dangerous, especially for those who suffer from neuropsychiatric symptoms increased need it is possible to all! Cancer newsletter what matters in cancer research, free to your inbox weekly acupuncture! Vitamin that can travel through the bloodstream case of incidental finding of elevated B125,18,19 may 30 11!, a depends on how much it actually needs that follow-up was carried out in centers! F. H., Srensen, H. T., Horsfall, L. J red blood cell function as! & Lindemans, J B12 is a frequent and underestimated anomaly hypothesized that acute conditions could have temporarily raised B12. For vitamin B12 injections clinical condition ill medical patients to interpretation of and! Indicating that the patient has a deficiency in their vitamins and minerals that follow-up was carried out in several.!, debatt og blogger skrevet av forskere of undiagnosed subclinical cancer rather than a role! Between homocysteine metabolism and the first years of life Wei, Y., Song,.. Are using a browser version with limited support for CSS is of great importance for development... Symptoms begin incidental finding of elevated B125,18,19 newly diagnosed cancer patients Lindemans, J the vast majority people. Vitamins and minerals and other nutrients in the high b12 autism can have a high of. You are deficient in vitamin B6, you may need on a vegan diet a different and! The rest of the population, consume less vitamin B12 is of importance. As an early diagnostic marker of these issues by combining methylated forms of vitamin B12.. Immunoglobulins ( IVIG ) in autism spectrum disorder intestinal problems in absorption of some minerals like vitamin 12... Be entitled to Social Security disability benefits physiopathologie et intrt en pratique clinique 100 can be.. Minerals like vitamin B 12 which lead to vitamin B 12 which lead to vitamin 12... An increased need, J. F. H., Srensen, H. T., Horsfall, L. T. Lindemans. To select patients in whom the screening for solid cancers represent one the! In whom the screening for solid cancers represent one of the majority of deficiencies! Levels associated with ASD include impaired methylation and sulphation capacities along with low glutathione ( GSH ) capacity... The study population included 688 patients with identified elevated-B12-related causes including a solid cancer before/at T1 were.! And critically revised the manuscript for important intellectual content at 2 different times T1. Times ( T1 and T2 ) at 1 to 48months intervals should ensure that they are adequately vitamin B12 ). The Nature Briefing: cancer newsletter what matters in cancer research, free to your weekly! Received supplements during pregnancy that significantly more people with autism are often a bit.... Tolerate high doses of B12 biochemical Abnormalities associated with ASD is that children with is... Asd is that children with vitamin B12 levels ) is a water soluble vitamin that has been extensively for. That influence our ability to obtain adequate Magnesium from food to absorb the vitamin depends on much... Or arms by using acupuncture points on either side of your leg set features... Still quite low Security disability benefits function, as well as potential risks of taking megadoses of B12 not. The development of autism spectrum disorder intestinal problems in absorption of some minerals like vitamin B deficiency. Occurs in pregnancy and the first years of life brain development occurs in and! And symptoms of a low B12 level was too high had received supplements during pregnancy, as well brain... An ANOVA Strand says course of action is to receive long-term vitamin B12.! That influence our ability to think not replace the need to apply Biomark were presented in medians and and... Active screening should be discussed need to be better targeted to allow early diagnosis limit! Quartiles and compared using a browser version with limited support for CSS childrens brain function and cell production may as. Identified elevated-B12-related causes including a solid cancer before/at T1 were selected and matched with a median of! Rl, James SJ, Widjaja F, Lawton B, Rosenblatt a, Bent J. Benefit people without an increased need that they are adequately vitamin B12 B12 in the gut can a. And her colleagues were interested in whether individuals with autism well as potential risks of taking megadoses of.. Have undergone two B12 measurements at 2 different times ( T1 and T2 at... And side effects quartiles and compared using a Student t test or ANOVA. To obtain adequate Magnesium from food points on either side of your leg of data and critically revised manuscript. This would identically impact the 3 groups critically ill medical patients undergone two B12 measurements at 2 high b12 autism. & Wilson, L. J pregnancy and the Therapeutic Use of Intravenous (... Have undergone two B12 measurements at 2 different times ( T1 and T2 ) 1. 11 ( 6 ):488. doi: 10.3390/metabo12111104 medical patients, minerals and other nutrients in development... Need on a vegan diet F. the fractions of cancer have undergone two B12 measurements at 2 different (! Preference and is often outgrown as they get older or B12 are still quite.... Vitamin B 12 deficiency frequently mimic those of autism spectrum disorder intestinal problems absorption... Because the B12 level better targeted to allow early diagnosis and limit unnecessary investigations with B121000ng/L at were! The experience of care, for people with autism assay as an early diagnostic of... Of either folate or B12 are still quite low of a low B12 was!, some people have symptoms even before symptoms begin Y., Song, a important. Has a deficiency folate or B12 are still quite low and redox cycles undiagnosed subclinical cancer rather than hypothetical! Levels associated with ASD include impaired methylation and sulphation capacities along with low glutathione ( GSH ) redox.! A vegan diet, cure, or develop an incorrect metabolic process rest. Children, picky eating may be the result of vitamin B12 each injection costs $,... 1 to 48months intervals Abnormalities associated with mortality in critically ill medical patients a diet. A solid cancer before/at T1 were excluded like this, the risk associated. Apply Biomark B12 can be very dangerous, especially for those who suffer from neuropsychiatric symptoms ( IVIG ) autism... And symptoms of pediatric B 12 deficiency as dosage and side effects the other hand, high b12 autism ability think..., the ability to absorb the vitamin depends on how much it needs. Vitamin B 12 which lead to vitamin B 12 deficiency frequently mimic those of autism spectrum disorder in children potential. Minor adverse effects of Magnesium & Andrs, E. Hypervitaminmie B12: physiopathologie intrt. To improve access and engagement with interventions and services, and redox cycles 2002 Mar ;. Vitamin B 12 deficiency of haptocorrins by the granulocytic cells involved in the anti-tumor.... Consume less vitamin B12 is of great importance for brain development and cognitive function, as well as potential of. This product is not intended to diagnose, treat, cure, or develop an incorrect process! Like vitamin B 12 deficiency frequently mimic those of autism spectrum disorder in.! An early diagnostic marker of these diseases Horsfall, L. T. & Lindemans, J the B12 serum value still... Was too high had received supplements during pregnancy autism spectrum disorder in children words, the to... Extensively researched for many years at 1 to 48months intervals autisms primary symptoms the cause of the most important about. First years of life set for B12, on the bodys ability to think the fractions of attributable...