Coenzyme Q10 (CoQ10) and Heart–Metabolic Wellness: A Science-Based Overview

What Is CoQ10?

Coenzyme Q10, or CoQ10, is a naturally occurring compound found in the mitochondria of almost every cell in our bodies.

It is particularly concentrated in organs with high energy demands, such as the heart, liver, and muscles.

As consumers, we may see it labeled in different forms:

• Ubiquinone (oxidized form) or ubidecarenone (the World Health Organization’s official name for ubiquinone)
• Ubiquinol (reduced form)

Inside the body, the two forms of CoQ10 are constantly changing back and forth.

One form (ubiquinone) picks up energy in the form of electrons, then switches into the other form (ubiquinol), which delivers that energy to the cells.

After giving it away, it changes back (to ubiquinone) again.

This cycle keeps repeating to help your cells keep running.

 

CoQ10 and Health

CoQ10 contributes to the production of adenosine triphosphate (ATP), the molecule that fuels energy for cells.

It also acts as an antioxidant, supporting our body’s natural defenses against free radicals and helping keep our cells healthy.

Researchers have studied CoQ10 in relation to several aspects of wellness, including heart and metabolic health.

To understand this further, we comprehensively reviewed the best available human studies on the topic.

While we’ll go into the high-quality human studies in more detail soon, here’s the main takeaway from what researchers have found so far:

• Blood lipids and sugar: Findings are inconsistent. Some studies suggest possible support, but more research is needed.
• Blood pressure (BP): Evidence is more consistent in showing potential support for maintaining healthy systolic blood pressure (SBP).*

There are some ways how CoQ10 may support healthy BP:

• It helps the body maintain nitric oxide, a natural compound that keeps blood vessel working smoothly.
• By protecting blood vessel health, CoQ10 may help promote healthy blood flow and flexible blood vessels.

*Supporting healthy SBP is important because it may support our long-term heart health, as suggested by substantial research findings that have been generally consistent over the past few decades.[1],[2]

 

Natural Changes in CoQ10 Levels

Our bodies produce CoQ10 naturally, but levels tend to decline with age.

Lifestyle factors—such as ongoing stress, dietary patterns, or certain medications—may also affect CoQ10 status.

As a result, the body’s natural supply of CoQ10 may not always keep pace with its needs.

Because CoQ10 is important for energy and heart health, many people take it as a supplement to help support healthy energy levels and overall wellness.

 

CoQ10 From Food

Before looking at research on CoQ10 supplements, let’s first see how much of it we get from food.

CoQ10 is naturally found in many foods, both plant and animal.

Richer dietary sources include oily fish, like salmon, tuna, and sardines.

Plant foods like whole grains, nuts, and beans also contain CoQ10, but usually in much smaller amounts than animal foods.

Still, the actual amounts in food are quite low.

For example, to reach about 40mg of CoQ10, we would need to eat either:

• More than seven (7.3) pounds of boiled soybeans,
• Over a pound (1.3) pounds of sardine (5-6 small tins), or
• More than 4,000 cups of raw spinach leaves

Because it’s hard to get meaningful amounts through diet alone, supplements can offer a practical way to help maintain healthy CoQ10 levels in the body.

 

What Does Human Research Show?

As we did for berberine and bergamot, we comprehensively reviewed high-quality human studies on CoQ10.

These include published randomized controlled trials (RCTs)—studies that compare CoQ10 to a placebo or to other supplement ingredients—and look at markers like blood lipid, sugar, or pressure in people.

We also reviewed meta-analyses of RCTs, which combine findings from multiple studies to give a big-picture view of the overall evidence.

Because almost all published RCTs and meta-analyses to date have tested the ubiquinone form of CoQ10, that is our focus in this section.

We’ll be comparing ubiquinone and ubiquinol findings shortly below.

Our review identified several meta-analyses of human RCTs examining CoQ10 and measures across heart and metabolic health, summarized in the table below.

Table. Meta-analyses of Human RCTs on CoQ10 and Markers of Heart and Metabolic Health   

*There may be individual RCTs that overlap across the meta-analyses

**In the studies summarized, results showed a statistically significant difference between CoQ10 and the comparator group for at least one outcome measured in the review. This does not mean that all individuals will experience the same effect.

***HbA1c captures average blood sugar over the past 2-3 months, while fasting blood glucose provides a snapshot of blood sugar at a single point in time

Why would we like to see more evidence on CoQ10’s support for blood lipid markers?

• Results so far are mixed with different conclusions for different cholesterol and triglyceride markers across multiple meta-analyses

Why would we like to see more evidence on CoQ10’s support for blood sugar markers?

• Two of the three meta-analyses showed conflicting results between two key blood sugar measures: HbA1c and fasting blood glucose

Why do we think there is stronger evidence for CoQ10’s support of healthy SBP, even though more research would be valuable?

• The majority of scientific evidence suggest CoQ10 may support healthy SBP levels
• In these studies, supportive effects were often seen at daily intakes of 100–200 mg

 

Putting It Together

Taken together, the evidence suggests CoQ10 may support heart and metabolic health, with the most consistent findings for SBP.

For consumers seeking broader support across multiple markers of heart and metabolic health, CoQ10 may be helpful.

Because research on blood lipid (cholesterol / triglycerides) and sugar has shown mixed results, supplements that combine CoQ10 with other ingredients could offer additional support and value.

We encourage you to discuss with your healthcare providers and supplement manufacturers to find the approach that best suits your health needs.

 

Ubiquinone vs. Ubiquinol

Most CoQ10 supplements on the market contain ubiquinone, the oxidized form of CoQ10.

In the body, ubiquinone is converted into ubiquinol, the form that acts as an antioxidant.

Some supplements provide ubiquinol directly, which is often claimed to have higher absorption (“bioavailability”).

 

There are a few important points to keep in mind:

 

There Is Much More Research Available on Ubiquinone Than Ubiquinol

• A recent review (2023) looked at the evidence for CoQ10 and heart and blood vessel health. It found over 60 clinical trials using ubiquinone, compared to fewer than 5 with ubiquinol.[3]
• We did not find any meta-analyses focused only on ubiquinol and heart or metabolic health.
• We also did not find RCTs of ubiquinol specifically related to normal blood pressure.

 

High-quality Human Studies of Ubiquinol Show Mixed Findings

• Studies comparing absorption of ubiquinone and ubiquinol show inconsistent results—some suggest higher absorption of ubiquinol[4] while others do not.[5]
• Available clinical research has not shown a clear advantage of ubiquinol over ubiquinone or even placebo for supporting heart or metabolic health:
• One RCT found that ubiquinol may help support healthy blood vessel function compared to placebo.[6]
• Another RCT found no difference between CoQ10 and placebo for supporting healthy blood sugar and lipid levels.[7]
• There is also no reliable scientific evidence on how to convert doses between ubiquinone and ubiquinol.

 

What This Means for Consumers

For an overview, see Figure 1 below for a simple comparison of the two forms of CoQ10.

From a consumer’s perspective, ubiquinol involves more uncertainty—about dose, expected benefits, and value for money.

Because the evidence base is much larger for ubiquinone, and results for ubiquinol remain limited and mixed, we believe that ubiquinone currently appears to be the more reliable option for consumers seeking CoQ10 support.

That said, research on ubiquinol is still developing, and future studies may provide new insights.

We look forward to following the science and updating our perspectives as new evidence emerge. 

 

Figure 1. CoQ10 Forms Compared: Ubiquinone vs. Ubiquinol

 

 

Final Words

Scientific research on CoQ10 has been ongoing for several decades and continues to expand.

So far, studies suggest CoQ10 may help support aspects of heart and metabolic health, with the most consistent findings related to maintaining healthy blood pressure.

We hope this overview of CoQ10 provides a helpful introduction for those interested in learning more about CoQ10 and how it may fit into your overall approach to wellness.

Stay curious, stay well.

 

Sincerely,

Derek Tang, PhD, MS, BSPharm

Truth Full Health

Your Trusted Supplement Partner

 

Disclaimer: All blogged content is for informational purposes only and does not replace professional medical advice. Statements made about vitamins or supplements (officially called “dietary supplements”) have not been evaluated by the U.S. Food and Drug Administration (FDA). Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare provider before beginning any new supplement, diet, or lifestyle program. To comply with FDA and FTC requirements, we summarize published research for general educational purposes only and do not make disease-treatment claims or unsubstantiated statements about any product. We encourage readers to review the cited studies and to contact us with general questions; we cannot provide individualized medical advice.

 

[1] Title: Age-specific relevance of usual blood pressure to vascular mortality: a meta-analysis of individual data for one million adults in 61 prospective studies. First author: S. Lewington. Journal: The Lancet. Year of publication: 2002.

[2] Title: Pharmacological blood pressure lowering for primary and secondary prevention of cardiovascular disease across different levels of blood pressure: an individual participant-level data meta-analysis.
First author: K. Rahimi. Journal: The Lancet. Year of publication: 2021.

[3] Title: Comparison of Coenzyme Q10 (Ubiquinone) and Reduced Coenzyme Q10 (Ubiquinol) as Supplement to Prevent Cardiovascular Disease and Reduce Cardiovascular Mortality. First author: J-P. Fladerer. Journal: Current Cardiology Reports. Year of publication: 2023.

[4] Title: Comparison Study of Plasma Coenzyme Q10 Levels in Healthy Subjects Supplemented With Ubiquinol Versus Ubiquinone. First author: P. H. Langsjoen. Journal: Clinical Pharmacology in Drug Development. Year of publication: 2014.

[5] Title: Comparative Bioavailability of Different Coenzyme Q10 Formulations in Healthy Elderly Individuals.
First author: I Pravst. Journal: Nutrients. Year of publication: 2020.

[6] Title: Ubiquinol Ameliorates Endothelial Dysfunction in Subjects with Mild-to-Moderate Dyslipidemia: A Randomized Clinical Trial. First author: J Sabbatinelli. Journal: Nutrients. Year of publication: 2020.

[7] Title: Effect of Liquid Ubiquinol Supplementation on Glucose, Lipids and Antioxidant Capacity in Type 2 Diabetes Patients: A Double-Blind, Randomised, Placebo-Controlled Trial. First author: C Yen. Journal: British Journal of Nutrition. Year of publication: 2018.