Research has found Coenzyme Q10 supplements to have a number of health benefits including treating heart failure, lowering inflammation, reducing oxidative stress, improving symptoms in chronic fatigue syndrome, fibromyalgia and much more.
Coenzyme Q10 (CoQ) is an essential component of the mitochondrial electron transport chain and an antioxidant in plasma membranes and lipoproteins. It is endogenously produced in all cells by a highly regulated pathway that involves a mitochondrial multiprotein complex.
Having personally experienced plasma Coenzyme Q10 deficiency, I know the role that the likes of secondary Coenzyme Q10 deficiency can play in causing various health problems such as chronic fatigue and major depression.
I have also experienced some significant health benefits such as increased energy, improved exercise capacity, reduced depression and less shortness of breath on exertion from taking Coenzyme Q10 supplements regularly and CoQ10 firmly remains one of my favorite nutraceuticals.
Anyway let’s take a look at the current scientific research and evidence-based health benefits of Coenzyme Q10.
Coenzyme Q10 & Heart Failure
Myocardial tissues of cardiovascular disease (CVD) patients are reported to be deficient in CoQ10.
In patients with congestive heart failure, myocardial CoQ10 content tends to decline as the degree of heart failure worsens. 
A 2-year treatment with CoQ10 (300 mg/day) as adjunctive therapy in a randomized, controlled multicenter trial affecting 420 patients suffering from chronic heart failure (Q-SYMBIO trial) demonstrated an improvement in symptoms and reduction in major cardiovascular events (Mortensen et al., 2014).
The systematic review concluded:
Evidence suggests that the CoQ10 supplement may be a useful tool for managing patients with heart failure. 
Coenzyme Q10 Lowers Inflammatory Biomarkers
Inflammation plays a key role in the development of most chronic degenerative diseases, especially cardiovascular disease.
A systematic review and meta-analysis published in 2017 evaluated the effects of coenzyme Q10 (CoQ10) supplementation on inflammatory mediators including C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by analyzing published randomized controlled trials (RCTs).
The systematic review/meta-analysis concluded:
In conclusion, this meta-analysis of RCTs suggests significant lowering effects of CoQ10 on CRP, IL-6 and TNF-α. 
Coenzyme Q10 Reduces Oxidative Stress
Coenzyme Q10 supplementation has been shown to reduce oxidative stress markers in a number of different patient groups including autism spectrum disorder, coronary artery disease, and individuals with relapsing-remitting multiple sclerosis.
Oxidative stress is defined as a disturbance in the balance between the production of reactive oxygen species (free radicals) and antioxidant defenses. Much like chronic inflammation, oxidative stress also plays a key role in the development of atherosclerosis and most other major degenerative diseases.
Coenzyme Q10 is an intracellular antioxidant that protects the membrane phospholipids, mitochondrial membrane protein, and low-density lipoprotein-cholesterol (LDL-C) from free radical-induced oxidative damage. 
Based on the results, high doses of CoQ10 can improve gastrointestinal problems and sleep disorders in children with ASD’s(Autism Spectrum Disorders) with an increase in the CoQ10 of the serum. We concluded that the serum concentration of CoQ10 and oxidative stress could be used as relevant biomarkers in helping the improvement of ASDs. 
Present study suggests that CoQ10 supplements at a dose of 500 mg/day can decrease oxidative stress and increase antioxidant enzyme activity in patients with relapsing–remitting MS. 
Coenzyme Q10 supplements at a dose of 150 mg can decrease oxidative stress and increase antioxidant enzyme activity in patients with coronary artery disease(CAD). A higher dose of coenzyme Q10 supplements (>150 mg/d) might promote rapid and sustainable antioxidation in patients with CAD. 
Coenzyme Q10 Deficiency & Chronic Fatigue Syndrome/ME
Coenzyme Q10 deficiency has been shown to play a role in the pathophysiology of Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and that symptoms such as chronic fatigue, autonomic and neurocognitive symptoms, may be in part caused due to CoQ1o depletion.
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a medical illness characterized by disorders in inflammatory and oxidative and nitrosative (IO&NS) pathways.
The study published 2009 in the Neuro Endocrinology Letters didn’t only find that Coenzyme Q10 deficiency plays a role in the pathophysiology of ME/CFS, but that lower levels of CoQ10 are another risk factor explaining the early mortality in ME/CFS due to cardiovascular disorder.
The study concluded:
Our results suggest that patients with ME/CFS would benefit from CoQ10 supplementation in order to normalize the low CoQ10 syndrome and the IO&NS disorders.
The findings that lower CoQ10 is an independent predictor of chronic heart failure (CHF) and mortality due to CHF may explain previous reports that the mean age of ME/CFS patients dying from CHF is 25 years younger than the age of those dying from CHF in the general population. 
Statin-Induced Coenzyme Q10 Depletion
Hydroxyl-methylglutaryl coenzyme A reductase inhibitors or statins interfere with the production of mevalonic acid, which is a precursor in the synthesis of Coenzyme Q10.
Studies have routinely shown that statin drugs result in lower Coenzyme Q10 levels in both serum and muscle tissue.
Statin-induced CoQ10 depletion is well documented in animal and human studies with detrimental cardiac consequences in both animal models and human trials.
A 2010 study published in The Ochsner Journal concluded:
Given the low risk of toxicity and the potential benefit in treating statin-induced myopathy, a trial of 200 mg of coenzyme Q10 daily should be considered for these patients. 
Coenzyme Q10 for the treatment of heart failure: a review of the literature
 Coenzyme Q10 in the treatment of heart failure: A systematic review of systematic reviews.
 Effects of coenzyme Q10 supplementation on inflammatory markers: A systematic review and meta-analysis of randomized controlled trials.
 The Relationship between Coenzyme Q10, Oxidative Stress, and Antioxidant Enzymes Activities and Coronary Artery Disease
 Coenzyme Q10 supplementation reduces oxidative stress and decreases antioxidant enzyme activity in children with autism spectrum disorders.
 Coenzyme Q10 supplementation reduces oxidative stress and increases antioxidant enzyme activity in patients with relapsing–remitting multiple sclerosis
 Coenzyme Q10 supplementation reduces oxidative stress and increases antioxidant enzyme activity in patients with coronary artery disease.
 Coenzyme Q10 deficiency in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is related to fatigue, autonomic and neurocognitive symptoms and is another risk factor explaining the early mortality in ME/CFS due to cardiovascular disorder.
 Coenzyme Q10 and Statin-Induced Mitochondrial Dysfunction
 The clinical use of HMG CoA-reductase inhibitors and the associated depletion of coenzyme Q10. A review of animal and human publications.
 Coenzyme Q10 Supplementation in Aging and Disease
The information in this article has not been evaluated by the FDA and should not be used to diagnose, cure or treat any disease, implied or otherwise.