Coenzyme Q10 (CoQ10)
Coenzyme Q10 helps to maintain a healthy cardiovascular system. There is evidence of CoQ10 deficiency in heart failure. Recently, CoQ10 plasma concentrations have been demonstrated as an independent predictor of mortality in chronic heart failure, CoQ10 deficiency being detrimental to the long-term prognosis of chronic heart failure. CoQ10 is available as medicine in several European countries, but is in these countries also available as a food supplement. Oxidation of the circulating LDL is thought to play a key role in the pathogenesis of atherosclerosis, which is the underlying disorder leading to heart attack and ischemic strokes and CHD. Studies in the last decade have demonstrated that the content of Ubiquinol in human LDL affords protection against the oxidative modifications of LDL themselves, thus lowering their atherogenic potency.
Supplementation of coenzyme Q10 has been found to have a beneficial effect on the condition of some sufferers of migraine headaches. So far, three studies have been done, of which two were small, did not have a placebo group, were not randomized, and were open-label, and one was a double-blind, randomized, placebo-controlled trial, which found statistically significant results despite its small sample size of 42 patients. Dosages were 150 to 300 mg/day.
Another recent study shows a survival benefit after cardiac arrest if coenzyme Q10 is administered in addition to commencing active cooling of the body to 90–93 degrees Fahrenheit (32–34 degrees Celsius).
There are several reports concerning the effect of CoQ10 on blood pressure in human studies.
A recent (2007) meta-analysis of the clinical trials of CoQ10 for hypertension reviewed all published trials of coenzyme Q10 for hypertension, and assessed overall efficacy, consistency of therapeutic action, and side-effect incidence. Meta-analysis was performed in 12 clinical trials (362 patients) comprising three randomized controlled trials, one crossover study, and eight open-label studies. The meta-analysis concluded that coenzyme Q10 has the potential in hypertensive patients to lower systolic blood pressure by up to 17 mm Hg and diastolic blood pressure by up to 10 mm Hg without significant side-effects.
Studies have shown that diseased gum tissue is deficient in CoQ10 compared to healthy gum tissue. Human clinical trials have suggested a link between oral administration of CoQ10 and improved gingival health, immune response in gum tissues, and a reversal of the diseased gum conditions. In addition to oral supplementation, topical application of CoQ10 on gum tissues has been shown to improve periodontitis and gingivitis conditions.
One study demonstrated that low dosages of coenzyme Q10 reduce oxidation and DNA double-strand breaks, and a combination of a diet rich in polyunsaturated fatty acids and coenzyme Q10 supplementation leads to a longer lifespan in rats. Coles and Harris demonstrated an extension in the lifespan of rats when they were given coenzyme Q10 supplementation. But multiple studies have since found no increase in lifespan or decrease in aging in mice and rats supplemented with coenzyme Q10. Another study demonstrated that coenzyme Q10 extends the lifespan of C. elegans (nematode).
Coenzyme Q10 concentrations in foods and dietary intake
Detailed reviews on occurrence of CoQ10 and dietary intake were published recently. Besides endogenous synthesis, CoQ10 is also supplied to the organism by various foods. However, despite the scientific community’s great interest in this compound, a very limited number of studies have been performed to determine the contents of CoQ10 in dietary components. The first reports on this issue were published in 1959, but the sensitivity and selectivity of the analytical methods at that time did not allow reliable analyses, especially for products with low concentrations. Developments in analytical chemistry have since enabled a more reliable determination of CoQ10 concentrations in various foods (Table below).