In the brain, 1C metabolism plays an important role in methylation, the breakdown of fats, and DNA repair. 

Vitamin B12, folate (aka vitamin B9), and choline are all highly influential in these pathways—primarily through their role in the methylation of homocysteine to methionine. 

Now, studies link high amounts of circulating homocysteine in the blood to poor brain health and even Alzheimer’s disease, stroke, and vascular dementia (dementia from blood flow problems). 

So low intake levels of these nutrients (or poor absorption of them), can lead to high homocysteine levels and negatively impact the brain. 

While these nutrients are found naturally in the diet, this new review summarizes the important role of supplementation for additional health benefits.