Co-enzyme Q10

Co-enzyme Q10 is present in all our cells. It has two major roles in our body.

  1. It is an integral part of the energy factories inside our cells, that are called mitochondria. It works by enabling oxygen to be broken down, producing energy as a result. As such it accounts for about 95% of our energy requirements, which means that it is pretty important for the correct functioning of our body, and especially our muscles.
  2. CoQ10 is also a powerful antioxidant that prevents fats being oxidised. Oxidised fats can cause inflammation, and a number of other problems. Unfortunately levels of CoQ10 decrease as we get older. Typically we have half the amount when we are 50 compared to when we are 20 years old. Whether this means we should supplement it is a pertinent question.

It is a fat soluble compound that exists in three forms: ubiquinol, semiquinone and ubiquinone. These three forms represent increasing states of oxidation. This ability to be in various oxidation states is the key to how it can act as both an effective anti-oxidant, and as an integral part of the energy creating machinery in our mitochondria.

Can it improve athletic performance?

There is some evidence that CoQ10 can help improve time to exhaustion in graded exercise tests. These improvements have been seen in young subjects (mean age 26), but are likely to be more impressive with older atheletes, who will have less CoQ10 in their muscle and heart tissues. The effects of CoQ10 supplementaton on athletic performance appear to be felt fairly quickly. One study reported improvements both within a few hours, and after 2 weeks of regular CoQ10 supplementation(1).

Can it improve health?

Co Q10 has been used for a number of conditions and could be considered as a potential supplement in the following situations.

Post heart surgery

Heart surgery can starve the heart muscle of oxygen. Restoration of the oxygen supply  (reperfusion) can cause oxidative damage from free radicals. It has been found that supplementation with CoQ10 (100-300mg/day) for a week, 2 weeks before surgery can reduce hospital stays and increase the efficiency of the heart pumping mechanism(1a).

Post heart attack

CoQ10 has been used immediately after major heart attacks in conjunction with total body cooling. The CoQ10 seemed to enhance survival quite significantly in a small group of 49 patients. 17 out of 25 CoQ10 patients survived for another 3 months compared to only 7 out of 24 in a placebo group(2).

Heart failure

The levels of CoQ10 in plasma in patients with congestive heart failure is lower than normal. This has led to a number of trials of CoQ10 in heart failure patients. Some have been positive(3) and other have shown little improvement(4). Virtually all heart failure patients are on a number of medications. Some of these medications interact with CoQ10 and so it is difficult to assess the usefulness of CoQ10 on its own.


The use of CoQ10 in hypertensive individuals does seem to lower systolic and diastolic blood pressure. Many studies have used doses ranging from 100-120mg day over a period of 2-3 months. The results have been quite consistent and show a reduction of around 17mmHg in systolic pressure and 10mmHg in diastolic pressure(5).


Like those with congestive heart failure, people with diabetes tend to have lower levels of coQ10 in their plasma. There is not much evidence that supplemental coQ10 changes blood sugar or insulin levels in diabetic patients. However, it could be useful when countering heart disease risk, which is greater for those with diabetes. For instance many diabetics have impaired flexibility of their arteries. One study has demonstrated that levels of coQ10 can partially relax arteries in diabetics using coQ10 supplementation at 200mg/day for 12 weeks(6).


CoQ10 has not been found to help particularly with female egg quality. However, it does help make sperm more motile. In particular, for men with low sperm motility and/or low levels of CoQ10 in their plasma, CoQ10 supplementation has been found to improve the shape of the sperm and their ability to swim to their destination(7).

Co Q10 and statin therapy

Very common drugs, known as statins are used to treat heart disease, and often to lower cholesterol even when heart disease is not present. Unfortunately statins have a number of side effects which can impact on the health of people taking them. One of these is muscle pain and weakness. In many who take statins these side effects can be quite severe. 

One of the reasons for this muscle pain is that statins lower the levels of CoQ10 in the plasma. One study supplemented people taking statins with 100mg/day of CoQ10 for a month. This produced a 40% reduction in a pain severity score system, used to assess levels of muscle pain(8).

If you take statins and suffer with muscle related symptoms, CoQ10 supplementation could prove worthwhile.

Testing for CoQ10 deficiency

It is possible to test for CoQ10 levels in the blood directly. I use Biolab for this test, and it is relatively cheap c. £25. Normal levels in the blood are 0.55-2.0mmol/l(9).

Should I supplement?

As with most supplements, it will normally only be effective for you if you are already deficient in CoQ10. This is more likely to be the case as you get older.

I would give it serious consideration if you are on statins, have high blood pressure, suffer with a mitochondrial disease, have diabetes or are a man wanting to improve your sperm motility. If you are an older athlete it may also be worth a try. Don't take without medical supervision if you are on blood thinning medication.

There are many companies that produce coQ10. They include: This lists the ingredients. Either 30mg or 100mg tablets. High absorption versions contain a black pepper extract, bioperine. Has free UK delivery. is another possibility. 60mg tablets with a high absorption formulation.

Look out for soft gels rather than powdered forms as these are more easily absorbed. Supplementation with CoQ10 has been found to be pretty safe with no serious side effects ever reported to date.

CoQ10 in food

CoQ10 can be found in foods containing fat, especially in organ meats and oily fish. Other meats are reasonable sources, and to some extent nuts and seeds also.



1a) (study 3)