The findings underline the potential protective effect of vitamin E on heart health, which remains disputed by inconsistent findings. But they also found the vitamin-like substance CoQ10 to reduce an inflammation marker by a further 20 per cent.
Inflammation and oxidative stress are key factors in the development and progression of vascular diseases, including heart disease, the world's biggest killer.
The US and Australian researchers tested the combination supplement over a two-week period on 21 baboons that had previously been fed a high-fat, high-cholesterol diet for seven weeks.
The vitamin E (DL-alpha tocopheryl acetate) reduced blood levels of C-reactive protein, a well-established marker for inflammation, from 0.91 to 0.43 mg/dL, a 53 per cent reduction.
Additional supplementation of 2g CoQ10 per kg diet, donated by the leading supplier Kaneka, further reduced serum CRP by nearly 70 per cent, reveals the study in this month's American Journal of Clinical Nutrition (vol 80, no 3, pp 649-655).
Such findings have also been shown in a trial on mice.
"This result is remarkable given that the baboons did not have any inflammatory condition at the time of the study and the two-week high-fat, high cholesterol diet did not initiate a significant inflammatory response," reported the researchers.
"In light of the fact that elevated CRP has been associated with vascular dysfunction which is in turn associated with cardiovascular disease, the results from our study suggest an anti-inflammatory effect of dietary supplementation with vitamin E plus CoQ10," they added.
The study is limited by the small number of animals involved. In addition, extrapolation of the results to humans is problematic : there are some differences in metabolic profiles, noted the researchers.
However it is one of the first to show that co-supplementation of vitamin E with CoQ10 may achieve better protection against inflammation-related vascular diseases.
The body's manufacture of CoQ10 begins to drop after the age of about 20, leading to its investigation in age-related disease. It has been shown to help prevent Parkinson's and is also thought to prevent skin ageing, significantly boosting demand in recent years to more than $200 million across the US alone.
DSM Nutritional Products yesterday presented an Innovation Award to a group of scientists involved in developing what it claimed was the world's first formulation of CoQ10 that can be pressed into tablets.
US multivitamin brand One-Source was first to use the product, followed by Perrigo and Walmart in May 2004. Additional formulations for food are in the pipeline.