So what is CoQ10 and why should I care?

Coenzyme Q10, more commonly referred to as CoQ10, is a nutrient your body makes naturally and also gets from food. But more on that in a second.

When my cardiologist put me on a statin after my heart attack, the conversation was pretty short. Take this, it lowers your cholesterol, come back for your follow up. I walked out with a prescription and a vague sense that I was now officially a person who takes a statin (along with a couple of other meds).

It didn’t occur to me to understand HOW my statin worked, only that it did. Which was great news — I had pretty high cholesterol numbers so I needed it to work. But then my mother in law mentioned that I should look into taking CoQ10 if I was on a statin. Maybe you’ve seen it at the store in the heart health area and wondered what it was for. What I didn’t know was how my statin was affecting MY CoQ10, never mind that I should care if it did.

So what is CoQ10 exactly?

Your body makes CoQ10 naturally and also gets it from food. CoQ10 lives mainly in your mitochondria, which are essentially the power generators inside your cells. CoQ10 is one of the key players in converting the food you eat into ATP, the actual energy currency your body runs on. Your heart, which never gets a day off, is one of the most CoQ10-dependent organs you have. So is your skeletal muscle.

Beyond energy production, CoQ10 also acts as a fat-soluble antioxidant, helping protect cell membranes from oxidative damage.

Here’s where statins come in.

The part nobody mentions in the prescription handout

Statins work by blocking an enzyme called HMG-CoA reductase, which controls a critical step in something called the mevalonate pathway. That’s the biochemical chain your body uses to produce cholesterol. Block the pathway, less cholesterol gets made. Exactly as intended.

The problem is the mevalonate pathway doesn’t only make cholesterol. It also produces CoQ10. So when statins interrupt the pathway, CoQ10 production drops as a consequence. That’s not a flaw in the drug. It’s a predictable result of a drug working exactly as designed. The same mechanism doing the thing you want it to do is also doing this other thing.

How much does CoQ10 drop? Multiple studies have looked at this, and the answer depends on the statin type and dose. Most research shows circulating CoQ10 levels falling by roughly 25 to 40 percent, with some trials reporting larger reductions. That’s a meaningful drop for a nutrient your heart and muscles depend on.

A lot of cardiologists know this. Whether it comes up in a ten-minute appointment is another matter, and I’m not here to criticize anyone for that. There’s a lot to cover. But it’s worth knowing, and worth asking about.

What does that actually feel like?

Honestly, hard to say with certainty. Low CoQ10 isn’t something you might feel in a clean, obvious way. It doesn’t announce itself with a specific symptom you can point to. The symptoms, if you get them, could look a lot like other things: persistent fatigue, muscle discomfort, a general sense of running on less than full. Which also happens to describe what normal aging feels like, low magnesium levels feel like, and what some statin side effects feel like, and what the months after a cardiac event feel like. Separating the contributors is genuinely difficult.

That uncertainty is exactly why researchers have spent decades studying CoQ10 directly.

The most cited trial is Q-SYMBIO, published in JACC Heart Failure in 2014. It randomized 420 patients with chronic heart failure to either CoQ10 at 300mg per day or placebo for two years. The CoQ10 group had substantially lower rates of major adverse cardiovascular events and significantly lower all-cause mortality. Subsequent summaries report relative risk reductions in the low-40 percent range for major cardiovascular outcomes. It remains one of the largest and longest randomized CoQ10 trials in heart failure.

A 2024 meta-analysis in BMC Cardiovascular Disorders pooled 33 randomized controlled trials and found CoQ10 significantly reduced all-cause mortality and hospitalizations in cardiovascular disease patients. A separate GRADE-assessed review from Advances in Nutrition in 2022 found CoQ10 reduced systolic blood pressure by about 4 to 5 mmHg across patients with cardiometabolic disorders, with 100 to 200mg per day identified as the effective range.

That’s a reasonably solid body of evidence for something that doesn’t come up in most post-discharge conversations.

A note on form, because it matters

CoQ10 exists in two forms. Ubiquinone is the oxidized form, the one you’ll find in most generic supplements because it’s cheaper to produce. Ubiquinol is the reduced, active form your body actually uses. Both forms will raise CoQ10 levels in your body. The difference is in how efficiently your body gets there. That conversion from ubiquinone to ubiquinol tends to become less efficient with age and in people managing chronic conditions, which is why some clinicians favor ubiquinol for older patients.

I’m not a doctor, and this isn’t medical advice. But if CoQ10 is something you’re looking into, the form is worth paying attention to. Ask your doctor. Look at what the research actually uses.

At the end of the day, I find it a bit odd that this isn’t mentioned more routinely when statins are prescribed. Maybe it’s because the evidence in general populations is less clear-cut than in heart failure specifically, and doctors reasonably want to stay on solid ground. And some supposed statin-related side effects like muscle pain could be caused by a number of other factors and get blamed on a statin. What is generally accepted, based on clinical trials, is that CoQ10 supplementation has a good safety profile at typical studied doses, and raising circulating CoQ10 has been associated with better outcomes in several cardiovascular conditions. Whatever the reason, I think it’s worth knowing that the relationship between statins and CoQ10 exists, and worth having the conversation.

Because you only get one heart. ‘Til next time, Stephen.

Sources

Mortensen, S. A., et al. (2014). The effect of coenzyme Q10 on morbidity and mortality in chronic heart failure: Results from Q-SYMBIO, a randomized double-blind trial. JACC: Heart Failure, 2(6), 641–649. PMID: 25282031.

Xu, J., et al. (2024). Efficacy and safety of coenzyme Q10 in heart failure: A meta-analysis of randomized controlled trials. BMC Cardiovascular Disorders, 24(1), 592. PMID: 39462324.

Zhao, D., et al. (2022). Effects of coenzyme Q10 on blood pressure: A GRADE-assessed systematic review and meta-analysis. Advances in Nutrition, 13(6), 2180–2194. PMID: 36130103.

Qu, H., et al. (2018). The effect of statin treatment on circulating coenzyme Q10 concentrations: An updated meta-analysis of randomized controlled trials. European Journal of Medical Research, 23, 57. PMID: 30414615.

Kelly, P., Vasu, S., Gelato, M., McNurlan, M., & Lawson, W. E. (2005). Coenzyme Q10 improves myopathic pain in statin-treated patients. [Conference abstract]. (No PMID available.)