Juvenon Health Journal 2014 – June 2014, No. 5
According to U.S. News and Report, Coenzyme Q10 (or CoQ10 for short) is the third most popular supplement in the United States. CoQ10 supplementation is prescribed by many doctors for treating or preventing a range of conditions from headache relief to Parkinson’s disease.
Today, CoQ10 is a $700 million global business. Over 6 million North Americans consume CoQ10 daily. It is not only marketed as an antioxidant, but also as an anti-ageing compound, a therapy for heart health and a prophylactic against the toxicity of statin drugs. Doctors are both recommending and prescribing CoQ10 for these and other conditions under the assumption that the supplement is beneficial to mitochondrial health.
But is this theory wrong? Given CoQ10’s popularity, one would assume there’s copious research to support these important health claims. However, there is no real evidence that CoQ10 supplementation does what doctors think it does. In this month’s Juvenon Health Journal we expose the truth about this popular supplement.
Understanding Coenzyme Q10
Coenzyme Q10 is a critical biological compound, which plays a central role in cellular bioenergy generation and its regulation. It can be found in most cells of the body with the highest concentrations found in the cells of your heart, kidneys, liver and the most metabolically active and mitochondrially rich tissues.
CoQ10’s mystique as a nutritional supplement surely stems from its presumed association with the mitochondria. Its physiological mechanisms seem to include presumed antioxidant effects in addition to its well-characterized role as a cofactor in multiple metabolic energy pathways.
CoQ10 plays a central role in cellular bioenergy generation and its regulation. In our bodies, CoQ10 functions as an electrical component in our mitochondria. If it sounds pretty important, it is.
CoQ10: Your Mitochondria’s Battery
Recall that protein complexes within our mitochondria biochemically convert nutritional fuels into electrical charges and ultimately, Adenosine Triphosphate, the biological currency of energy. These protein complexes, known as the electron transport chain (ETC) are always anchored within the mitochondrial membrane, the layered lipid sheets that form the overall structure of the mitochondria. These lipid membranes form the physical features of cells and also serve to anchor proteins and protein complexes. In its native function, CoQ10 resides within the lipid membrane layer of the mitochondria and functions to move electrical charges between components of the ETC.
In this fashion, CoQ10 functionally resembles a very small battery. Or, perhaps more accurately, a capacitor, which means that it can temporarily hold electrical charges and also participate as an antioxidant. As it turns out, the most important aspect of CoQ10 as a nutritional supplement isn’t its bioelectrical function, but its molecular nature. CoQ10 is very lipophilic– meaning ‘oil like’. Lipophilic molecules dissolve in oil, while hydrophilic molecules dissolve in water. Very few molecules do both.
Exposing The Supplementation Theory Flaw
CoQ10 is a cofactor, which means that it is a required factor for proper enzymatic activity. However, CoQ10 is not a required nutrient and thus not actually a vitamin. In fact, the body synthesizes and recycles natural CoQ10 rather efficiently.
One interesting twist of biochemistry is that the natural CoQ10 in your body is made by the same metabolic machinery that also synthesizes cholesterol. Indeed chronic use of statin drugs seems to lower natural CoQ10 levels. So there is some rationale behind its co-administration with statins. But, does dietary supplementation of such a specific biochemical really help out the native metabolic pathways in which it typically functions?
Since CoQ10 is synthesized in every cell, in close locational relation to the actual mitochondrial machinery that utilize it, is there any reason at all to think that the CoQ10 you take is absorbed by the gut and finds its way to your mitochondria?
Indeed, a recent meta-analysis of a large array of CoQ10 clinical trials determined that there was no improvements in cardiac function, repair or mortality. The study pointed out that the only common ‘improvement’ was increased serum CoQ10 levels.
Are You Wasting Your Money on CoQ10?
CoQ10 is sold as a nutritional supplement and is intended to provide mitochondria with more antioxidants and electron shuttling power. Anecdotally, the supplement has been associated with improvements in free radical scavenging, cardiovascular function, diabetes, hypertension and much more. Of course, a lot of supplements are marketed with such claims.
The problem lies in bioavailability and takes us back to the oil-and-water concept. Most CoQ10 supplements show bioavailability of less than 15%. Eighty-five percent or more of the supplement just passes through the gut unabsorbed. Even with such low bioavailability, oral supplementation with CoQ10 is known to increase blood and lipoprotein concentrations of CoQ10 in humans.
Of course, it has to be absorbed and transported within the bloodstream via lipoproteins — microscopic oil vesicles — since it does not dissolve in water. However, to date, there is no evidence that orally supplemented CoQ10 ever makes it into other tissues beyond the bloodstream, let alone the mitochondria.
In addition to bioavailability being limited by its lipophilic nature, CoQ10 is also a relatively large and cumbersome molecule, which physiologically isn’t typically transported around the body. So, while CoQ10 is certainly a mitochondrial cofactor physiologically, nothing in the research suggests that it is a mitochondrial nutrient when taken as a supplement.
Possible CoQ10 Benefits
Indeed, much of the supposed healthy effects noted in clinical testing of CoQ10 seem likely due to its antioxidant function in the bloodstream. Much like vitamin E, CoQ10 may contribute to cardiovascular health simply by preventing some of the associated oxidative spoilage of lipoprotein vesicles — a completely passive side effect. CoQ10 is safe and relatively inexpensive. Despite the dearth of scientific evidence questioning its efficacy and marketing claims, many people do report improved well-being. CoQ10 is definitely safe enough for that task, but if you’re taking it for your mitochondria’s sake, you might think again.
How To Crack the Mitochondrial Barrier
If you are interested in your mitochondrial health on a molecular level, there are supplements that verifiably do become transported to the mitochondria. A vast body of research literature demonstrates that dietary lipoic acid and carnitine are rapidly absorbed and transported to tissues including passing the blood-brain-barrier. In tissues, these nutrients are readily taken into mitochondria and demonstrate improved mitochondrial function and positively associated clinical outcomes.
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