Having been doing quite well I have taken quite a sudden turn of dizziness and cognitive problems over the last 3 days. I am receiving 3 times a week B12 injections along with 5mg folic acid. I have also been taking Thorne Basic B complex. Levothyroxine 100/112.5 alternating.
What are the issues and symptoms from taking too much folic acid? I am concerned about methylation - I haven’t done any genetic testing, but I am autistic and it seems methylation is often a problem for autistic people. Folinic acid seems to be mentioned in papers about autism - I think this is different again?
Are folate tests subject to false highs with folic acid if methylation is poor? Recent test was 20 - so right at the top of the range (3-20) but I wasn’t given any advice to stop taking the folic acid. I’m in a bit of a black hole with the GPs - had just found a really good one but she is now on sick leave.
I might also post this on the Pernicious Anaemia group but I think this group has provided better methylation info in the past - I’m just struggling to find the right bits just now. A Facebook B12 group I’m in doesn’t allow discussion of methylation
I feel inclined to stop the folic acid and take methyl folate instead. Does that sound sensible?
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5 mg is a large dose available prescription only. Many people, including myself, can’t tolerate a dose as large as this. When I took it, I had dizziness, insomnia and agitation.
It had been prescribed by a neurologist. My GP stopped it and prescribed the OTC dose of 400 mcg. My folate levels rose very quickly.
Who prescribed for you? If Folate is at top of range I’m surprised you need it. Methyl folate will be ok at lower dose of 400 mcg.
Thank you. It was prescribed by a neurologist - my email to him has gone unanswered. I got the sense that he felt that as long as I was having frequent B12 injections that I should also take the folic acid. Interesting to hear it caused you dizziness too. I have had dizziness in the past when my folate and b12 were definitely low but I had felt it had got a lot better until this episode which is worse than ever!
Thanks, I think I will stop the separate folic acid and go with what is in the B complex.
If you are already taking a source of folate (as you say), I'm not convinced that taking 5 milligrams more makes any sense. Remember, that dose is very largely because doctors cannot prescribe any other dose - there are no lower-dose products that are available approved for prescribing.
This is from what I regard as a good quality and official USA site. (Being in the USA does affect some of the information but with a little thought, it is just as relevant here.)
The quite below is way beyond my understanding and experience but is offered as a potentially interesting and relevant reference.
Health Risks from Excessive Folate
Large amounts of folate can correct the megaloblastic anemia, but not the neurological damage, that can result from vitamin B12 deficiency. Some experts have therefore been concerned that high intakes of folate supplements might mask vitamin B12 deficiency until its neurological consequences become irreversible. Questions about this possibility still remain, but the focus of concern has shifted to the potential for large amounts of folate to precipitate or exacerbate the anemia and cognitive symptoms associated with vitamin B12 deficiency [2,85,148-153].
Concerns have also been raised that high folic acid intakes might accelerate the progression of preneoplastic lesions, increasing the risk of colorectal and possibly other cancers in certain individuals [1,3,60,80,81]. In addition, intakes of 1,000 mcg per day or more of folic acid from supplements during the periconception period have been associated with lower scores on several tests of cognitive development in children at age 4–5 years than in children of mothers who took 400 mcg to 999 mcg [154].
Intakes of folic acid that exceed the body’s ability to reduce it to THF lead to unmetabolized folic acid in the body, which has been linked to reduced numbers and activity of natural killer cells, suggesting that it could affect the immune system [5,155]. In addition, some scientists have hypothesized that unmetabolized folic acid might be related to cognitive impairment among older adults [156]. These potential negative health consequences are not well understood and warrant further research [1,9].
Studies have found unmetabolized folic acid in blood from children, adolescents, and adults [1,5,157,158]; breastmilk [159]; and cord blood from newborns [160,161]. Limited research suggests that single doses of 300 mcg or 400 mcg folic acid (a common amount in folic acid-containing supplements or servings of fortified foods, such as breakfast cereals) result in detectable serum levels of unmetabolized folic acid, whereas doses of 100 mcg or 200 mcg do not [162,163]. In addition, a dose-frequency interaction appears to occur in which smaller amounts of folic acid consumed more frequently produce higher unmetabolized folic acid concentrations than the same total dose consumed in larger, less frequent amounts [164].
Based on the metabolic interactions between folate and vitamin B12, the FNB established a UL for the synthetic forms of folate available in dietary supplements and fortified foods (Table 3) [2]. The FNB did not establish a UL for folate from food because high intakes of folate from food sources have not been reported to cause adverse effects [2]. Thus, unlike the RDAs, the ULs are in mcg, not mcg DFE. For folic acid, 1,000 mcg is equivalent to 1,667 mcg DFE because 0.6 mcg folic acid = 1 mcg DFE [11,164]. The ULs do not apply to individuals taking high doses of supplemental folate under medical supervision [2]
Thank you. I didn’t know that was all they could prescribe. My brain is a bit too befuddled to take in all that but the “some scientists have hypothesized that unmetabolized folic acid might be related to cognitive impairment among older adults” has stood out….I am going to stop taking it just now! Thank you
Further, the cost of folic acid from supermarkets is so low, it would be ridiculous for anyone in England not entitled to prescription charge exemption to get them prescribed!
Please have a look at blog.cytoplan.co.uk/nutrigenomics-and-autism/. The speaker in the blog:Nutrigenomics and Autism, is someone I have thought of consulting. If I remember correctly, both she and her son were very ill with M.E. I think her son is autistic. She was an intensive care nurse who broke away to a new career to find a way of regaining her health, and that of her son. Her son now has a degree and a very good job. She emphasises the importance of Vitamin B6 where autism is concerned, and discusses Folate and Vit B12, and the interplay between the 3 vitamins. It is about a lot more than these 3 vitamins, but if you read it I think you will find it interesting. It may explain why folate and B12 alone are causing you problems. There are other research papers you can google if you put , "autism and Vit B6" into the search box. You could also search "autism and Folate deficiency or B12 deficiency".
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