Co-enzyme Q10 (CoQ10) is a vitamin-like substance present in most body cells, where it assists the generation of energy-rich molecules within the mitochondria, which act rather like your cells’ batteries. Cells which work the hardest – heart, skeletal muscle and liver cells for example – contain the most mitochondria and therefore need the most CoQ10.
After the age of 20, your blood levels of CoQ10 start to decrease for two reasons: you absorb dietary CoQ10 less efficiently, and the amount made in your cells start to decline. By the age of 40, the amount of CoQ10 present in heart muscle and artery lining cells is up to 32% lower than when you were in your 20s, for example.
Without CoQ10, cells cannot convert the energy hidden in food molecules into energy, so they function less efficiently. Muscle cells in artery linings are less able to dilate and contract to normalise blood pressure and, when levels become significantly low, heart muscle contraction can be impaired.
Research suggests that falling CoQ10 levels play a significant role in age-related medical conditions such as hypertension, coronary heart disease, heart attack and heart failure. Biopsies from patients with various forms of heart disease have shown that up to 75 per cent are deficient in CoQ10, and lower levels of CoQ10 are associated with more severe heart disease. As a result, some doctors in the United States and Japan use co-enzyme Q10 supplements to treat coronary heart disease and heart failure.
How co-enzyme Q10 lowers blood pressure
CoQ10 improves the elasticity and reactivity of artery walls. Adding 225 mg CoQ10 to existing anti-hypertensive drug regime was found to produce significant, gradual improvements in blood pressure in a group of 109 people with hypertension. Just over half (51%) were able to stop between one and three of their antihypertensive drugs (under the supervision of a cardiologist) within 4.4 month after starting CoQ10. Those whose heart contraction was assessed also showed a significant improvement in left ventricular wall thickness and function so heart pumping became more efficient. Only three per cent of patients required the addition of one antihypertensive drug.
Analysis of data from 3 trials, involving 96 people, found that coenzyme Q10 supplements taken by people with hypertension (blood pressure greater than 140/90 mmHg) reduced their readings, on average, by 11/7mmHg compared with inactive placebo. A larger analysis, which used data from 12 clinical trials, involving over 360 people, found that CoQ10 could reduce BP by up to 17/10 mmHg compared with placebo, without significant side effects. This included a cross-over trial, in which the same group of people took coenzyme Q10 or placebo for a period of time, then crossed over to take the other treatment (so they acted as their own controls). Their blood pressures were, on average, 11/8mmHg lower when they were taking the co-enzyme Q10 supplements than when they were taking the dummy treatment.
As well as making co-enzyme Q10 in your cells, you obtain small amounts from cell-based foods such as offal, meat, fish, whole grains, nuts and green leaves. Average daily dietary intakes are estimated at up to 5mg for meat eaters and 1mg daily for vegetarians.
The effect of statins
Statin drugs lower cholesterol levels by blocking an enzyme (HMG-CoA reductase) needed to synthesise cholesterol. This same enzyme is needed within cells to produce co-enzyme Q10 so levels fall quickly when you start take statin medicine – typically dropping by halve within two to four weeks. This may contribute to the muscle-related side effects some people experience when taking a statin (as may the fact that statins reduce vitamin D synthesis). Taking co-enzyme Q10 supplements (eg ubiquinol 100mg or ubiquinone 200mg) helps to maintain blood levels of this important muscle nutrient without affecting the cholesterol-lowering action of the statin.
Doses of co-enzyme Q10
Co-enzyme Q10 is available in two forms: ubiquinol, which is the most active, and ubiquinone which your cells must convert into ubiquinol before it can work. This conversion becomes increasingly less efficient with age, so if you are over the age of 40 it’s best to select the ubiquinol form.
The ‘body-ready’ ubiquinol is usually taken at a dose of 100mg per day.
Ubiquinone is usually taken at doses of 60mg to 200mg per day. Higher doses of 600mg per day have been used in clinical trials, but it is best to only take higher doses under medical supervision.
As it is oil soluble, supplements are best taken as gel caps in which the CoQ10 is dissolved in oil, and consumed with food to improve absorption. Co-enzyme Q10 appears to be a safe supplement with few side effects (apart from the lowering of blood pressure).
If your blood pressure is borderline or raised, self-monitoring is key to maintaining good control.
Click here for advice on choosing a blood pressure monitor to use at home.
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