Coenzyme Q10

What is coenzyme Q10?

Coenzyme Q10 is a fat-soluble compound required for the activity of enzymes involved in the energy production in the body cells ^[1]. Coenzyme Q10 is also called ubiquinone, because of its ubiquitous presence in the humans, animals, plants and microbes, and because it belongs to quinones – a group of fat-soluble compounds with a cyclic structure.

Coenzyme Q10 is a nonessential nutrient, which can be produced in your body, so you do not need to get it from foods in order to be healthy. No minimal dietary intake of coenzyme Q10 has been recommended by medical institutions ^[1].

Coenzyme Q10 Functions in the Human Body

Coenzyme Q10 (CoQ10) is ^[1]:

• Required for the conversion of energy from foods to energy-storing molecules ATP
• An antioxidant in the cell membranes and lipoproteins (molecules that transport fats in the blood)

Coenzyme Q10 is present in all body tissues, especially in the liver, pancreas, heart and blood vessels ^[1].

Foods High in Coenzyme Q10

Foods (red meat, poultry, fish) are not considered a good source of coenzyme Q10 ^[1].

Coenzyme Q10 Deficiency

Low coenzyme Q10 blood level may occur in:

• Cancer, chronic alcoholism, chronic malnutrition, diabetes mellitus, heart failure, HIV/AIDS, hypermetabolism, muscular dystrophies, old age, Parkinson’s disease, shock, smoking, treatment with statins (cholesterol-lowering drugs) and in vigorous physical exertion ^[1,2].
• Rare genetic diseases ^[4]:
  • Encephalomyopathy with myoglobinuria, brain involvement and ragged red fibers
  • Severe infantile multisystemic disease
  • Cerebellar ataxia (musle incoordination)
  • Leigh syndrome with growth retardation, ataxia and deafness
  • Isolated myopathy (muscle disease)

Common symptoms include generalized muscle weakness ad seizures.

Coenzyme Q10 Supplements

Nonprescription synthetic coenzyme Q10 supplements are available as tablets, powder or oil-containing capsules. The amount of coenzyme Q10 in supplements is about 10-100 times higher than in foods ^[1].

Coenzyme Q10 from oral supplements can be detected in the blood, but it is not clear if it reaches the body tissues ^[1].

Coenzyme Q10 Health Benefits

Coenzyme Q10 is POSSIBLY EFFECTIVE in:

• Coenzyme Q10 deficiency due to certain genetic diseases (see above) ^[1,2,4,6]

Coenzyme Q10 supplements are POSSIBLY INEFFECTIVE ^[1,2,6] in the prevention or treatment of diabetes mellitus type 2 ^[6,16], hepatitis C, Huntington’s disease ^[9] and post-polio syndrome, or in improving exercise performance ^[18] or slowing aging.

There is INSUFFICIENT EVIDENCE ^[1,2] about the effectiveness of coenzyme Q10 supplements in the prevention or treatment of age-related vision loss (age-related macular degeneration) ^[6], Alzheimer’s disease ^[6], amyotrophic lateral sclerosis ^[6,8], angina pectoris (heart-related chest pain), asthma ^[6], atherosclerosis (artery hardening), cancer (breast, prostate or other), cataracts ^[6], cerebellar ataxia (uncoordinated movements), chemotherapy side effects ^[6,15], chronic fatigue syndrome (CFS), chronic obstructive pulmonary disease (COPD), cocaine dependence ^[6], complications of heart attack (myocardial infarction), congestive heart failure ^[12,18], coronary heart disease ^[6], dry mouth, cyclic vomiting syndrome, cystic fibrosis ^[6], dental (periodontal) disease, diabetic cardiomyopathy, endothelial dysfunction, fibromyalgia, Friedreich’s ataxia, gum disease, hair loss caused by a blood thinner warfarin, hearing loss, heart disease ^[10], high cholesterol ^[6], high blood pressure (hypertension) ^{[1,2,6,11,18]}, HIV/AIDS, hypertrophic cardiomyopathy, inherited diabetes and deafness, kidney failure, Lyme disease, male infertility, migraine ^[6], mitochondrial diseases ^[6,7], muscular dystrophy ^[6], myelodysplastic syndrome ^[6], nerve damage caused by diabetes (diabetic neuropathy) ^[6], Parkinson’s disease ^[6,14], Peyronie’s disease (painful erection in men) ^[6], pre-eclampsia (high blood pressure in pregnancy), psoriasis ^[6], statin-induced muscle weakness ^[6,17], tinnitus (ringing in the ears) and wrinkled skin, or in protection in heart bypass surgery ^[6,13], promoting weight loss, or as an antioxidant or immunity enhancer ^[6].

It is NOT KNOWN if coenzyme Q10 helps in abnormal heart rhythms, acidosis, adrenal insufficiency, anemia, Bell’s palsy, celiac disease, depression, eye disorders, gallbladder disorders, glaucoma, headache, hepatitis B, inflammation, mental performance, multiple sclerosis, muscle wasting, phenylketonuria, skin irritation caused by chemicals, stomach ulcer, systemic lupus erythematosus (SLE), viral infections, viral myocarditis (heart inflammation caused by virus) or vomiting ^[6].

Coenzyme Q10 Safety: Side Effects, Toxicity

Coenzyme Q10 supplements are LIKELY SAFE for most adults and POSSIBLY SAFE for children when taken by mouth in appropriate doses ^[2].

Side effects may include stomach upset, loss of appetite, heartburn, nausea, vomiting, diarrhea, low blood pressure and insomnia ^[1,2]. Allergic reactions (rash, difficulty breathing, lips swelling) to coenzyme Q10 are possible. Coenzyme Q10 may cause hypoglycemia in diabetic patients ^[3].

Coenzyme Q10 is not recommended during pregnancy and breastfeeding ^[1]. Children should not take coenzyme Q10 without doctor’s supervision. Speak with your doctor if you want to take coenzyme Q10 and you have diabetes, a heart disease, rheumatoid arthritis or any immune disease including HIV/AIDS.

Coenzyme Q10-Drug Interactions

Red rice yeast extract may decrease body coenzyme Q10 levels ^[2]. It is not clear if cholesterol-lowering drugs statins lower body levels of coenzyme Q10 ^[1].

Coenzyme Q10 may decrease the effect of an anticoagulant drug warfarin ^[1] and chemotherapy drugs ^[2] and increase the effect of blood pressure-lowering drugs ^[2]. Currently coenzyme Q10 is not recommended for prevention of statins (cholesterol-lowering drugs) side effects ^[5].