According to a new review, vitamin E seems to play an essential role in reducing the risk of diseases related to high cholesterol levels such as atherosclerosis and Alzheimer’s disease.
The review analyzed the results of large trials evaluating the association between intakes and serum concentrations of vitamin E and rates of diseases related to the accumulation of excess cholesterol in blood vessels and brain (1). The analysis of nine large epidemiological studies showed that high vitamin E intake from food and/or supplements significantly decreased the risk of cardiovascular diseases such as coronary heart disease (risk reduction between 5 and 65 percent) and stroke (15-60 percent). In addition, several epidemiologic and clinical studies showed efficacy for vitamin E, alone or in combination with vitamin C, in preventing against cognitive disorders such as Alzheimer’s disease or treating symptoms. Among the different preventive and therapeutic strategies dietary alpha-tocopherol supplementation has been shown in some studies to exert positive effects in the brain.
The possible preventative role of vitamin E against diseases related to high levels of cholesterol in the blood (hypercholesterolemia) includes antioxidant activities, anti-inflammatory functions, regulation of the expression of genes involved in growth, apoptosis and inflammation, as well as modulation of the immune response. Alpha-tocopherol was identified as the major antioxidant present in human lipoproteins. At the protein level, it was shown to act as signalling molecule in the regulation of cell growth, inhibiting vascular smooth muscle cell proliferation – a key factor in the atherosclerotic process. Also Alzheimer’s disease has been linked to increased oxidative stress and oxidative damage potentially reduced by vitamin E. Excess brain cholesterol has been associated with increased formation and deposition of plaque, which may contribute to the risk and development of the disease.
The researchers concluded that there is a large body of evidence connecting the effects of oxidative stress and related signalling mechanisms with hypercholesterolemia-induced age-related diseases. On the basis of the previous results, vitamin E can be accepted as an important protective factor against such diseases.