Study: Alzheimer's not prevented by antioxidants

So many sources tell us to take in more antioxidants--from green tea, from black tea, from fruit and vegetables, from supplements--but do they really make a difference? A paper published in Archives of Neurology suggests that, whatever else they might or might not do, extra antioxidants in the diet don't seem to make any difference for Alzheimer's disease biomarkers.

The reasoning between treating Alzheimer's disease with antioxidants is the spread of oxidative damage in the brain. A group of 78 people from the Alzheimer's Disease Cooperative Study (ADCS) Antioxidant Biomarker study, who had mild to moderate Alzheimer's disease, were given vitamin E, vitamin C, α-lipoic acid and coenzyme Q, a combination of antioxidants. The researchers tracked biomarkers in their spinal fluid.

"The combination of E/C/ALA did not affect CSF biomarkers related to αβ, tau or P-tau (which are related to AD)," the authors commented.

There was a drop in F2-isoprostane levels, a marker of oxidative stress in the brain, but along with this, there was an increase in decline in the Mini-Mental State Examination (MMSE), a measure of cognitive function. Though there may not be a definite connection, this raises a note of caution--as the researchers said, "It is unclear whether the relatively small reduction in CSF F2-isoprostane level seen in this study may lead to clinical benefits in Alzheimer's disease. The more rapid MMSE score decline raises a caution and indicates that cognitive performance would need to be assessed if a longer-term clinical trial of this antioxidant combination is considered."

The researchers concluded that the results do not support further clinical trial development of coenzyme Q in Alzheimer's disease. So, while it's important to keep eating your recommended five a day, don't look to it changing your chance of Alzheimer's disease. Keep doing the crosswords instead.

- read the release from Archives of Neurology
- see the abstract