Nutritional Advice El Mondo- Coenzyme Q10 (CoQ10) is a fat-soluble compound found naturally in virtually every cell in the human body.
- There are two forms of coenzyme Q10: ubiquinone and ubiquinol.
- Coenzyme Q10 occurs in diet as ubiquinone and in humans mainly as ubiquinol.
- The estimated daily intake of CoQ10 is 3-6 mg per day derived primarily from meat. Cooking by frying reduces CoQ10 content by 14-32%.
- Rich sources of dietary coenzyme Q10 (ubiquinone) include mainly meat, poultry and fish.
- Other relatively rich sources include soybean, canola oils and nuts.
- CoQ10 as ubiquinone plays a key role in producing energy in mitochondria in the form of ATP.
- Adequate amounts of CoQ10 are necessary for cellular respiration and ATP production.
- CoQ10 as ubiquinol also functions as an intercellular antioxidant.
- Alpha-tocopherol (vitamin E) and coenzyme Q10 (as ubiquinol) are the principal fat-soluble antioxidants in membranes and lipoproteins.
- Symptoms of coenzyme Q10 deficiency have not been reported in the general population, so it is generally assumed that normal biosynthesis and a varied diet provide sufficient coenzyme Q10 for healthy individuals.
- Dosages of 30-60 mg/day are recommended to prevent CoQ10 deficiency.
- CoQ10 deficiency may occur among statin-users because coenzyme Q10 shares a common biosynthetic pathway with cholesterol.
- Statins can reduce serum levels of CoQ10 by up to 40%. However, it may be emphasized that till date there are no conclusive reports that support the role of CoQ10 deficiency in the pathogenesis of statin-related myopathy.
- The biosynthesis of coenzyme Q10 involves three major steps:
- Synthesis of the benzoquinone structure from either tyrosine or phenylalanine, two amino acids;
- Synthesis of the isoprene side chain from acetyl-coenzyme A (CoA) via the mevalonate pathway and;
- The joining or condensation of these two structures.
- The enzyme hydroxymethylglutaryl (HMG)-CoA reductase plays a critical role in the regulation of coenzyme Q10 synthesis, as well as the regulation of cholesterol synthesis.
- Biosynthesis is the major source of CoQ10. Biosynthesis requires at least 12 genes and mutations in many of them cause CoQ10 deficiency.
- Adult human body pool has been found to be approximately 2 g and requires replacement of about 0.5 g/day based on its average turnover rate of about 4 days in various tissues.
- Ubiquinol is the most common form of coenzyme Q10 in vivo and accounts for more than 80% of the total ubiquinol+ubiquinone pool in human plasma, intestine and liver.
- Coenzyme Q10 levels are highest during the first 20 years of life and decline with age.
- At age 80, coenzyme Q10 levels may be lower than at birth.
- Coenzyme Q10 is absorbed from the small intestine, passes into the lymphatics and finally to the blood and tissues.
- Coenzyme Q10 is absorbed slowly from the gastrointestinal tract, possibly because it has a high molecular weight and is not very water-soluble.
- Coenzyme Q10 is best absorbed if it is taken with a meal. Peak plasma levels are achieved in 2-6 hours after oral administration.
- In healthy adults, normal values for CoQ10 are 0.8 to 1.5 micrograms per milliliter.
- CoQ10 may lower blood sugar levels.
- Taken orally, coenzyme Q10 has a low clearance rate, with an elimination half-life of about 34 hours.
- Administration of 100 mg CoQ10 3 times/day achieved a mean steady-state level that was estimated at 5.4 µg/mL.
- The tolerable upper limit intake is up to 1.2 grams per day. However, the usual dose is 100-200 mg/day in deficiency states and other disease states.
Scientific studies on the relationship between coenzyme Q10 and disease prevention:
Review articles of randomized, placebo-controlled double-blind clinical trials (RCTs) will answer the following question:
"Is taking dietary supplements make sense?". Yes at a positive conclusion and no at a negative conclusion.
Review articles of cohort studies or case-control studies will answer the following question:
"Should I change my diet?".