Coenzyme Q10 Is Good for More Than Just Your Heart

This heart-healthy antioxidant may be good for brain health too 
By Aaron W. Jensen, Ph.D.

Do you ever feel completely spent - totally exhausted because you've been going nonstop for days? You need a good long rest to allow yourself to recover and become reenergized. However, not all of yourself gets a rest. Think about it - your heart never stops beating (a good thing, if you want to stay alive), and your brain too has to keep on working even while you're asleep.

Your heart is a true workhorse. Every second of your life, this unique muscle (about the size of your clenched fist) contracts and supplies all the tissues of your body with nutrient-rich, life-preserving blood. Let's do some math: about 60 contractions per minute x 60 minutes per hour x 24 hours per day = 86,400 contractions per day. No doubt about it, that's a lot of work! And because your heart works constantly, it needs a constant energy supply.

A deficiency of CoQ10 in the 
mitochondria of Parkinson's 
patients is related to the disease 
process; supplementation may 
provide significant improvement.

The intense work performed by your brain is perhaps more difficult to appreciate. This organ, which weighs about 3 pounds (about 1.5% of your body weight), consumes about 20% of your body's oxygen intake. Oxygen is required for cellular respiration - the process in the brain (as well as the rest of the body) that converts glucose from your food into usable chemical energy. Why does your brain require so much energy? Because it is constantly controlling both voluntary and involuntary functions throughout the rest of your body, 24 hours a day, 7 days a week, month after month, year in and year out.

Coenzyme Q10 Is Vital for Energy

One important molecule that allows these organs to work nonstop is coenzyme Q10(often abbreviated CoQ10). This compound is found in every cell of your body - in the tiny organelles called mitochondria - and it participates in the production of cellular energy. The most active cells in the body (such as those of the brain and the heart) contain the most mitochondria, which means that they need the most CoQ10 to power them. Without adequate CoQ10, these hard-working organs may not perform optimally. This has been well documented for heart function, and recent research has demonstrated that CoQ10 is good for brain health too - especially in slowing the progression of at least one of the brain diseases associated with aging.

Parkinson's Disease Impairs Bodily Movement

Parkinson's disease (PD) is a neurological disorder that afflicts about 1% of American adults over the age of 65. The disease results from a loss of specific motor-control neurons (nerve cells), called dopaminergic neurons, from discrete locations in the brain. Neural signals that govern muscle movement and function are compromised, causing a breakdown in those circuits. The mind, however, remains unaffected, so the victims are able to think as clearly as ever and are well aware of their condition. (This contrasts starkly with Alzheimer's disease, in which the victims basically lose their minds and seem happily unaware of it).

The visible symptoms of Parkinson's include muscle tremors (often characterized by a "pill-rolling" movement, so called because of a constant rubbing of the thumb against the forefinger), slowed movement, muscular rigidity, and postural disturbance. Little is known about the origin of the disease, which frustrates effective treatment and makes prevention difficult.

CoQ10 Slows the Progression of Parkinson's

The Parkinson Study Group - a consortium of 13 research institutions throughout the United States - is attempting to identify effective therapies for treating the early signs of PD. This august group has made great progress and recently published an article in the Archives of Neurology demonstrating that CoQ10 supplementation slows the progression of PD in its early stages.1 That news is especially welcome, as no other treatment (pharmaceutical or otherwise) had previously been shown to do this. Hail CoQ10!

All Brain Diseases Are Not the Same

Parkinson's disease, Alzheimer's disease, Huntington's disease, and Lou Gehrig's disease (also called amyotrophic lateral sclerosis, or ALS), are some of the better-known degenerative neuronal diseases. In each of them, discrete regions of the brain and central nervous system degenerate and become dysfunctional with time.

The manner in which the brain is wired internally, as well as its myriad connections to motor neurons, is vastly complex, and slight alterations within this intricate system can have devastating results. Many degenerative disorders occur because there is a change in cellular signals used to communicate between neurons, via molecules called neurotransmitters. Changes in the function, release, level, or metabolism of these crucial signaling molecules (of which there are many different types) influence how the brain performs its many tasks.

In Parkinson's disease, the neurotransmitter dopamine is depleted, and this interferes with appropriate responses from muscle tissues. The function of acetylcholine is perturbed in Alzheimer's disease, inhibiting the essential transfer of information between neurons involved in cognition. Huntington's disease is characterized by a loss of gamma-aminobutyric acid (GABA), a neurotransmitter essential to integrating motor and mental functions. Lou Gehrig's disease results from altered metabolism of the neurotransmitter glutamate, which leads to motor-neuron degeneration and loss of motor function.

Clearly, these diseases are different in origin. Describing their causes simply in terms of changes in neurotransmitters is an oversimplification, but it helps to illustrate how diseases that afflict the same organ (the brain) can have very different clinical symptoms.

The researchers recruited 80 patients in the early stages of PD (early enough that they did not yet require treatment for their disability) to participate in the study. The patients were randomly assigned to one of four groups, receiving either placebo or 300 mg, 600 mg, or 1200 mg of CoQ10 per day; in addition, each group received 1200 IU of vitamin E per day. The patients' functional decline was monitored over the next 16 months, using the Unified Parkinson Disease Rating Scale (UPDRS). Included in this testing system are a mental score, a motor score (for muscle function), and a rating on activities of daily living (ADL) - a measure of one's ability to perform routine daily tasks, such as personal hygiene, food preparation, and just getting around.

CoQ10 Deficiency May Be Related to Parkinson's

The exciting result of this research is that all three of the CoQ10 doses decreased the rate of functional decline in the Parkinson's patients, based on their total UPDRS score, with the greatest effect being observed at the highest dosage, 1200 mg/day.* The results of all the individual components of the UPDRS score were more favorable in the CoQ10 groups than in the control group, and all showed a trend toward decreased functional decline. The strongest response was found in the ADL test, and it was dose-dependent, with the highest dose producing the statistically most significant response. The mental score also showed improvement with increasing dosage.

*The doses of CoQ10 used in this study were much higher than those used in other clinical studies. For example, an effective dose used in many heart disease studies ranges from 50 to 200 mg/day. The most likely explanation for the difference in dosage requirements is that CoQ10's access to the brain is impeded somewhat by the blood-brain barrier (a brain-capillary membrane that protects the brain from most molecular invaders). Thus, higher blood levels of CoQ10 may be required for this nutrient to reach the brain than to reach the heart, which has no such barrier.

Although CoQ10 provided significant benefits to the Parkinson's patients, they were not immediate. After 1 month, the 1200-mg/day group showed a benefit in the ADL test. It took 4 months of daily treatment, however, before a clear separation emerged between the 1200-mg/day group and the control group in the total UPDRS score, and 8 months before such a separation emerged between the 300- and 600-mg/day groups and the control group. At the end of the 16-month trial, the change in total UPDRS score was most significant in the 1200-mg/day group.

"CoQ10 may also protect against 
other brain diseases associated 
with aging and the slowdown in 
mitochondrial function." 

The results of this study support the hypothesis that a deficiency of CoQ10 in the mitochondria of Parkinson's patients is related to the disease process and that correcting this deficiency through long-term supplementation may provide a significant measure of improvement. It should also be noted that CoQ10 treatment was well tolerated by the patients, although the incidence of mild adverse events was higher in the treatment groups than in the control group.

Free Radicals - The Price We Pay for Energy

We know that mitochondria are essential for chemical energy production in the brain (and throughout the body), but there is a price to pay for this energy. It may surprise you to learn that mitochondria produce huge quantities of free radicals, those destructive, oxidative molecular species that are implicated in many degenerative processes, including aging itself. And the cells that require the most energy, such as neurons in the brain, produce the most free radicals.

But if free radicals are so harmful, why would our mitochondria produce them? Let's be clear - this is not something the body wants to have happen, it's just an inevitable consequence of the chemistry of cellular energy production (much like the production of noxious carbon monoxide and nitric oxide as byproducts of gasoline combustion in automobiles).

CoQ10 Is an Important Antioxidant

The way that the body's cells guard against free radical damage is to amass an arsenal of free radical fighters - molecules called antioxidants. It happens that CoQ10 is a potent antioxidant, along with four others that are particularly important for protecting our cells: glutathione, lipoic acid, vitamin C, and vitamin E.* All these compounds play important roles in attacking and neutralizing dangerous free radicals before they do too much damage to our cells.

*In addition to coenzyme Q10, all but one of these antioxidants can be taken as nutritional supplements. The one that can't is glutathione, which does not survive the digestive process. Our cells make abundant glutathione, however, which is fortunate because it is the most vital antioxidant of all.

Might CoQ10 play an important role in rejuvenating the brain and protecting against neuronal degeneration? Professor Lester Packer of UC Berkeley, a renowned antioxidant researcher, thinks so. He notes in his book The Antioxidant Miracle that CoQ10 protects brain cells under conditions of oxidative stress and that "CoQ10 may also protect against other brain diseases associated with aging and the slowdown in mitochondrial function."2 The implication is that CoQ10 may have far-reaching and beneficial effects on brain function.

CoQ10 Is Good for Your Heart

CoQ10 has been used in Japan to treat congestive heart failure - as an approved drug, no less - since 1974. Clearly, there is sound scientific evidence to support its use for this disease, in which the heart pumps much less efficiently than it should, causing an accumulation of fluid in the lungs and other parts of the body. In addition, there is nearly 40 years of research supporting the beneficial role of CoQ10 in cardiomyopathy, a distinct type of heart failure due to an abnormally enlarged or stiffened heart that is restricted in its ability to pump blood.

The heart-healthy evidence for CoQ10 keeps piling up. Most recently, research has been published demonstrating that it lowers blood pressure.3 In this study, patients with high blood pressure (systolic pressure between 150 and 170 mm Hg) were administered 60 mg of CoQ10 and 150 IU of vitamin E twice a day for 12 weeks. At the end of the study, the average reduction in systolic pressure in the CoQ10 treatment group was a significant 25.9 mm Hg. This is an important result, as individuals who are able to lower their systolic blood pressure are likely to enjoy improved cardiovascular health, with reduced risks for stroke, heart failure, and overall mortality.

CoQ10 Is Essential for Good Health

Because of its vital role in the electron transport chain - the biochemical pathway in mitochondria that allows the body's cells to convert food to energy - coenzyme Q10 is essential for normal cellular function. Knowing that, it's easy to see why this molecule is essential for the good health of all our organs. As we age, however, our blood levels of CoQ10 gradually decrease. This may help to explain why the incidences of heart disease and neuronal degeneration increase as the years tick away. To keep your heart and mind ticking in sync with the years, coenzyme Q10 may be just the ticket.


  1. Shults CW, Oakes D, Kieburtz K, et al. Effects of coenzyme Q10 in early Parkinson disease: evidence of slowing of the functional decline. Arch Neurol2002;59:1541-50.
  2. Packer L, Colman C. The Antioxidant Miracle. John Wiley & Sons, New York, 1999, pp 92-104.
  3. Burke BE, Neuenschwander R, Olson RD. Randomized, double-blind, placebo-controlled trial of coenzyme Q10 in isolated hypertension. South Med J2001;94:1112-7.

Dr. Jensen is a cell biologist who has conducted research in England, Germany, and the United States. He has taught college courses in biology and nutrition and has written extensively on medical and scientific topics.