Choline Benefits: January 2009 Archives

This month's American Journal of Clinical Nutrition had a number of new papers on the topic of pregnancy and choline consumption.

The paper seems to be an effort by Dr. Zeisel, professor at the University of North Carolina, to help increase the visibility of Choline with other researchers.

In the paper, Dr. Zeisel notes:

"Evidence is growing that optimal dietary intake of folate and choline (both involved in one-carbon transfer or methylation) is important for successful completion of fetal development. Significant portions of the population are eating diets low in one or both of these nutrients.

Folates are important for normal neural tube closure in early gestation, and the efficacy of diet fortification with folic acid in reducing the incidence of neural tube defects is a major success story for public health nutrition. Similarly, maternal dietary choline is important for normal neural tube closure in the fetus and, later in gestation, for neurogenesis in the fetal hippocampus, with effects on memory that persist in adult offspring; higher choline intake is associated with enhanced memory performance."

Importantly, he notes, there is a wide variation in the amount of choline that people have in their diet (typically a variation of 3 to 4 fold)  and that in several studies it has been shown that  25% of women got less than the 6.7 mg/kg levels that are considered minimal.  Add to this the fact that different genetic makeup of people, means that different people need different levels of choline - and as of yet, there is no way to test for these genetic variations (or SNPs) - so its impossible for a person to know if they are getting enough (or their baby is getting enough) choline.

In the paper, Dr. Zeisel notes that "Changes in dietary availability of methyl groups induces stable changes in gene methylation, altering gene expression and resulting phenotype...Many of the changes in neurogenesis (the improved memory, etc.) caused by altered availability of dietary choline or folate during pregnancy are probably mediated by altered DNA methylation."

Interestingly, recent research has shown that "stress" that mammals (including humans) is a very effective at de-methylating DNA - and this is believed to be one of the leading contributors to mental illness - because the de-methylation exposes unhealthy genes that are the ultimate cause of a significant portion of the cases of mental illness.

I expect to see much more research in the area of how choline and other methy-donor supplementation during pregnancy may help reduce the risk of mental illness later in life.  As I've mentioned elsewhere in this blog, data from rodent studies and choline are already showing that this seems to be the case.  

In a second paper in this issue of the journal, Dr. Zeisel poses the question of whether supplementation for women of key brain-related nutrients like Choline is something that should be considered more. 

As he states:

"during perinatal development in which specific nutrients are required for optimal development, and there is growing evidence that optimal dietary intake of these nutrients, which include iodine, docosahexaenoic acid, choline, and folate, is important. ... For some of the nutrients discussed, such as iodine and folate, the effects in humans are abundantly clear; for others, animal data are the most convincing. More human studies need to be conducted."

My understanding is that human studies are currently underway for choline and prenatal supplementation.  One researcher I had lunch with noted that its his belief (and he's been researching choline for the past decade) is that EVERY woman should supplement with as much choline as she can.  He thought the research (which now numbers over 40 studies on the impact of Choline on the brain, done over the past 25 years) was already that compelling (and I tend to agree with him).  He was also disappointed with the pace of research being done in this area, as it seems to be the one of the most important areas of nutritional and prenatal development today.

Other researchers are much more cautious - as Dr. Zeisel noted at the end of the paper:

"It is clear that the dietary manipulation of methyl donors (either deficiency or supplementation) can have a profound effect on reproductive outcome through epigenetic mechanisms. For this reason, it is important that expert panels carefully consider recommendations for dietary intake of methyl donors during pregnancy."

 
See the research papers here:

Importance of methyl donors during reproduction (Steven Zeisel), American Journal of Clinical Nutrition

Is maternal diet supplementation beneficial? Optimal development of infant depends on mother's diet

(Steven Zeisel), American Journal of Clinical Nutrition