KUOPIO, FINLAND. Atherosclerosis is a disease of the arteries in which fatty, often calcified deposits develop on the inside of the arterial wall (intima) and eventually cause blockages that lead to cardiovascular disease (angina, heart attack and stroke). The progression of atherosclerosis can be followed by measurement of the thickness of the intima with ultrasonography.
Finnish researchers reported about 3 years ago that supplementing with a combination of vitamin C and vitamin E markedly reduced the increase in intima thickness. The researchers now report the results of a further 3 years of follow-up. The study involved 440 men and women between the ages of 45 and 69 years. All participants had cholesterol levels at or above 5.0 mmol/L (193 mg/dL) and both smokers and non-smokers were included. The participants were randomized into two groups – one receiving 136 IU of natural vitamin E (d-alpha-tocopherol) and 250 mg of slow-release vitamin C (ascorbic acid) twice daily with meals, the other receiving placebos.
The researchers observed an average annual increase in intima thickness of 0.014 mm in the placebo group as compared to 0.010 mm in the supplement group corresponding to a substantial 25% treatment benefit. Further analysis showed that the benefit was limited to male participants. Here the treatment benefit was 37% as compared to an insignificant 14% among women. The benefit of supplementation was greatest among participants with low baseline levels of vitamin C and among those with existing plaques in the carotid artery. Plasma levels of vitamin E and vitamin C increased by 57% and 38% respectively over the 6 years of supplementation.
The researchers emphasize that vitamins C and E must be taken together as vitamin C is needed for regeneration of vitamin E. It would also appear that it may be crucial to use natural vitamin E (d-alpha-tocopherol) rather than synthetic (dl-alpha-tocopherol) in order to achieve the desired effect. They point out that the treatment effect among participants who had carotid plaques at baseline was more than 50%. This is comparable to the effect of the most effective cholesterol-lowering drugs (statins), but with no adverse effects and at a much lower cost. Researchers at the UC Davis Medical Center suggest that the optimum regimen may well be 600-800 IU/day of natural vitamin E plus 500 mg/day of vitamin C.