Vitamin E is a powerful antioxidant found in nuts, seeds, eggs, whole grain foods, spinach, avocado, salad dressing and vegetable oils.
The role of Vitamin E in reducing the risk of dementia has been the subject of a number of studies. In the July edition of “Archives of Neurology” the results of a long-term study carried out by the Erasmus Medical Centre in Rotterdam, Holland, revealed the effect of four dietary antioxidants on dementia risk. Over 5000 people aged 55+ (who did not have dementia at the onset of the study), were followed for 9+ years. The study focused the intake of Vitamin E and C, beta-carotene and flavonoids.
In a previous study, the Rotterdam group had found that higher dietary intakes of Vitamin E and C were associated with a lower risk of Alzheimer’s and dementia.
The results of this longer term study though, showed that it was those people who consumed the highest amount of Vitamin E that had 25% less risk of developing dementia compared to those who consumed the least. The dietary intakes of Vitamin C, beta-carotene and flavonoids were not associated with changes in dementia risk. This was an unexpected finding, given the previous positive association link found with Vitamin C.
What about the use of Vitamin E as a supplement ?
Many clinicians routinely give their elderly patients high doses of Vitamin E and often in only one form. Vitamin E is actually a family of eight natural compounds and the one most commonly used is alpha–tocopherol.
A Swedish study looked at the levels of all eight natural vitamin E compounds in the blood of over 200 subjects. Here they found that those with the highest blood level of all of the vitamin E family had a reduced risk of developing dementia. This risk was reduced by between 45 to 54% depending on the individual Vitamin E component level. Dr Mangialasche in this study noted that the protective effect of the vitamin appears to be related to the combination of the different forms, suggesting that it is the balance of the 8 compounds, which may have the most important neuroprotective effect.
Another study also looked at the role of dietary Vitamin E along with a combination of certain other nutrients which have also been associated with a lower risk of dementia and Alzheimer’s disease.
Columbia University NY revealed the results of a four year study of 200 subjects over the age of 65 (none of whom had dementia). They identified several dietary patterns with varying levels of 7 nutrients, previously associated with Alzheimer’s risk. These included saturated fats, monosaturated fats, omega 3 fatty acids, omega 6 fatty acids, Vitamin E, B12 and folate. One pattern in particular was found to be associated with a significantly lower risk of Alzheimer’s and this was noted to include a high intake of the following:
Salad dressing Nuts Fish Tomatoes, Poultry Fruits Cruciferous vegetables Dark green leafy vegetables
This is pretty much the basis of the Mediterranean diet, which has previously been associated with a lower risk of Alzheimer’s and dementia.
The authors noted that the nutrients in the low risk dietary pattern reflected the multiple pathways in the development of Alzheimer’s disease.
i.e • Vitamin B12 and folate help to reduce the body’s levels of homocysteine (a risk factor for Alzheimer's) • Vitamin E has a potent antioxidant effect • Fatty acids assist in normal brain cell membrane function.
So where does that leave us now?
It may well be that including a higher amount of vitamin E rich foods in our diet may have a modest effect on reducing dementia risk. Unfortunately we don't know yet, how much is to be recommended. Meanwhile eating whole foods in a healthy combination diet based on the Mediterranean model is probably the way to go. Further studies are likely to continue to evaluate dietary intake of antioxidants and how they may modulate the risk of dementia.
References: American Academy of Neurology (2008, April 17). Vitamin E May Help Alzheimer's Patients Live Longer. Johns Hopkins University Bloomberg School Of Public Health (2004, January 20). Vitamin Supplement Use May Reduce Effects Of Alzheimer's Disease. Francesca Mangialasche, Miia Kivipelto, Patrizia Mecocci, Debora Rizzuto, Katie Palmer, Bengt Winblad, Laura Fratiglioni. High plasma levels of vitamin E forms and reduced Alzheimer's disease risk in advanced age. Journal of Alzheimer's Disease, 2010 JAMA and Archives Journals (2010, July 13). Eating foods rich in vitamin E associated with lower dementia risk.