One of the best things about this blog has been getting feedback from others. Recently, a commenter from the UK (thanks Emily!) pointed me to the PONTI (Prevention Of Neural Tube defects by Inositol) study. I’d never even heard of inositol before! Apparently some researchers think that inositol supplementation (on top of folic acid) may help to prevent neural tube defects.
As we’ve already discussed, folic acid is really powerful in reducing the number of NTD-affected pregnancies, but it does not eliminate them. One article suggests that “30–50 % of NTDs are not folate preventable. . . .”
Apparently, scientists have known for a while that inositol (here myo-inositol) prevents folate-resistant neural tube defects in mice:
They theorized this would be true in humans as well. A 2002 article reported that a woman with two nueral tube defect pregnancies (even with folic acid supplementation, ie. FA-resistant) used 500mg inositol with her third pregnancy, and had a healthy baby without any side effects to mom or baby:
Here’s another study noting no side effects to mom or baby with inositol:
And here’s one that suggests myo-inositol might be helpful in avoiding gestational diabetes:
In 2006, the PONTI study researchers noted that inositol helped to prevent NTDs in mice that were “folic acid resistant”: “We found that inositol prevents NTDs in a FA-resistant mouse model. Moreover, serum inositol is lower in mothers and children with NTDs. Pre-clinical animal testing, and limited testing in humans, suggest that inositol therapy is safe in pregnancy.”
Here’s the information about the PONTI study (which has been completed). Women with a history of a neural-tube affected pregnancy and were planning to become pregnant were given 5mg of folic acid (the standard UK supplement for pregnancies at high risk of NTD) and either 1 g inositol or a placebo.
Another study out of the Washington University has also found that, in mice, there is a link between inositol metabolism and NTDs:
Okay, before we go any further, what the hell is inositol? There are actually nine forms of inositol, although only two forms were discussed in any of the literature I reviewed: myo-inositol [the most widely-occurring in nature] and D-chiro-inositol.
Inositol was once considered a member of the vitamin B complex (formerly B8), but that’s no longer true.
Myo-inositol and D-chiro-inositol are chiral epimers of one another—they have the same chemical formula and weight, but different chemical structure. (Like your right and left hand, they are mirror images of one another but they do not have the same structure. Hmm, all that high school and college chemistry is coming in handy.) Some scientists think that your body makes D-chiro-inositol from myo-inositol. SO, if you are unable to convert D-chiro-inositol from myo-inositol, a D-chiro-inositol supplementation may help you. Other people who make the conversion, but with less than optimal efficiency, may benefit from large doses of myo-inositol. People in the middle may benefit from some of each. At the end of the day, though, people who need inositol are likely to see positive results from either one:
It can be purchased as an over the counter supplement in the US (not regulated by the FDA):
http://www.amazon.com/Jarrow-Formulas-Inositol-Powder-227g/dp/B0013OUKPC/ref=sr_1_1?s=hpc&ie=UTF8&qid=1445270219&sr=1-1&keywords=Inositol (226g powder of Myo-inositol for $15)
http://www.amazon.com/D-Chiro-Inositol-30-Caps/dp/B00HS41DSY/ref=sr_1_3?s=hpc&ie=UTF8&qid=1445270300&sr=1-3&keywords=D-chiro-inositol#customerReviews(D-chiro-inositol – expensive! 30 300mg tablets are $15, which means 3 mos of 900mg (just under 1g) would be $126)
http://www.amazon.com/Solgar-Inositol-Vegetable-Capsules-Count/dp/B00129AI6O/ref=sr_1_3?ie=UTF8&qid=1445270138&sr=8-3&keywords=Inositol+500+mg+Vegetable+Capsules+solgar (vegetarian, unclear what form)
Inositol has been studied as a treatment for PCOS, with findings that myo-inositol alone and myo-inositol along with D-chiro-inositol were both helpful, with the combination being particularly good.
Some amazing woman went through in amazing detail the use of inositol for PCOS:
It appears there are no results for the PONTI study yet:
I sent them an email to see if they would share their early results, but I’m not holding my breath. (ponti@ich.ucl.ac.uk) But there are a number of blogs (mostly from women in the UK, it appears) that suggest their doctors are proscribing inositol after a pregnancy has been affected with an NTD.
The dosage recommendation appears to be 1g of inositol (along with 5mg folic acid) for the first 12 weeks.
One study suggests that D-chiro-inositol is more effective than myo-inositol in preventing folate-resistant mouse neural tube defects:
So, am I going to take inositol? Hell yes I am. I have calls in to both my fertility doctor and my regular OB before I start it, but unless they give me some really damn convincing arguments why I should not take this, I am going to do it.
Fab post! I was instructed to take 1g on top of 5mg of folic acid. When I contacted the trial, they stated results were encouraging and we're going to expand it to a full sized study.
ReplyDeleteI take myo.
Hopefully the fab info you posted will help someone else
Xx