Homocysteine & Dementia (2011)
This was a meta-analysis* of eight studies, involving almost 9,000 subjects. The results found that at 5 µmol/l increase in homocysteine level was associated with a 35% increase in incidence of dementia.
The researchers could not conclude that raised homocysteine is an actual cause. However, they did estimate that if it was causal, we could expect an approximate 20% reduction in risk of dementia from treatment with folic acid and B12.
Click here for the abstract
Homocysteine and dementia – a clear association. Wald, Kasturiratne, & Simmonds (2011). Alzheimer’s and dementia 7: 412-417
*Meta-analysis: a collation and analysis of a group of studies on the same topic