This article in Nutrients. 2013 May 8;5(5):1531-43. doi: 10.3390/nu5051531 discusses the effects of a diet rich in folic acid, folic acid, or 5-MHTF (a type of folic acid) on patients with increased homocystine levels.
The study was double blind each group either received a diet with 200 mcg of folate, 200 mcg of folic acid, 200 mcg of 5-MTHF, or a placebo.
Reductions in homocysteine were seen in the diet group, the folic acid group and the 5MTHF of around 20%.
It would appear that all of these methods is an effective way of reducing homocystine.
Read More at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3708334/