CoQ10 and Diabetes
Diabetes is a chronic disease of impaired glucose regulation. It is characterized by elevated blood sugar, commonly referred to as hyperglycemia.
Diabetics are usually classified as one of two types:
Type 1 Diabetes
Previously known as juvenile diabetes, type 1 diabetes results from the body’s failure to produce insulin. Type 1 diabetes occurs more often in younger individuals. It is estimated that 5 -10% of Americans who are diagnosed with diabetes have type 1.
Type 2 Diabetes
Previously known as maturity onset diabetes, type 2 diabetes occurs more often in older individuals, although the age of onset is getting lower. Type 2 diabetes results from insulin resistance (a condition in which the body fails to properly use insulin), combined with relative insulin deficiency (the body does not produce enough insulin). Type 2 diabetes is the most common form of diabetes. It is estimated that 90 - 95% of Americans who are diagnosed with diabetes have type 2 diabetes. Risk factors for development of type 2 diabetes include obesity, family history of diabetes, advanced age, and a history of diabetes during pregnancy. Of these, obesity is the largest risk factor such that type 2 diabetes and obesity in America are increasing hand in hand. Type 2 diabetes is more common in African Americans, Latinos, Native Americans, and Asian Americans/Pacific Islanders.
The rise in diabetes in America is shown in the maps in the figure below with data collected by the Centers for Disease Control (CDC).

Let’s take a closer look at how diabetes affects the normal functions of the body. Glucose is the basic fuel used for energy production in the cells of the body. After a meal, blood glucose levels rise. In order for cells to turn food into energy, glucose must be effectively transported from the blood into the cells. Regulation of the transport of glucose from blood into the cells is achieved primarily by insulin, a hormone made by the pancreas. Insulin functions like keys which unlock the cells of the body allowing glucose to enter. In diabetes, blood sugar rises because either there is not enough insulin (not enough keys) or the available insulin does not work efficiently (the keys don’t work as well as they should).
When glucose builds up in the blood instead of going into cells, it can cause two problems:
- Immediately, cells may be starved for energy.
- Over time, elevated blood glucose levels may cause damage to “end” organs, such as the eyes, blood vessels and kidneys, leading to blindness, heart attack, stroke, kidney failure, and amputations.
Most people with diabetes have associated health problems - such as high blood pressure and cholesterol that increase one’s risk for heart disease and stroke. When combined with diabetes, these risk factors add up to big trouble. Diabetes is the leading cause of blindness and more than 65% of people with diabetes die from heart disease or stroke. With diabetes, heart attacks occur earlier in life and more often result in death. These heart attacks are usually due to atherosclerosis, the build up of cholesterol and fats that clog blood vessels. By managing diabetes, high blood pressure and cholesterol, people with diabetes can reduce their risk of cardiovascular disease.
Role of Coenzyme Q10 in Diabetes
Coenzyme Q10 has two functions in the body: (1) it is required to make energy in the form of ATP and (2) it is a powerful antioxidant. Both of these functions also play a role in the progression of diabetes.
ATP production
The synthesis of insulin by the pancreas requires energy in the form of ATP. Without ATP, insulin production is reduced. Because coenzyme Q10 is required for ATP production, adequate levels of coenzyme Q10 are needed for the normal regulation of blood glucose levels by means of insulin. Patients with type 2 diabetes have been found to have significantly lower blood levels of coenzyme Q10 compared with healthy non-diabetics. 1 This study suggests that a deficiency of coenzyme Q10 in the pancreas could impair the production of ATP and hence, the synthesis of insulin.
Antioxidant
When glucose is able to enter the cells, it can be metabolized using oxygen to produce energy in the form of ATP. Unfortunately, this process of aerobic metabolism also generates harmful oxygen free-radicals and other pro-oxidant molecules that contribute to oxidative stress. Oxidative stress has been associated with elevated blood glucose levels and is part of a problem known as “glucose toxicity”. Additionally, oxidative stress has the potential to damage organs, including the pancreas, further contributing to the diabetic disease process itself and increasing the risk of the cardiovascular disease associated with diabetes. 2 Coenzyme Q10 is a potent antioxidant that acts at the site of aerobic metabolism to scavenge oxidants and prevent oxidative stress. Accordingly, conditions that increase oxidative stress will increase the consumption of coenzyme Q10 to be used as an antioxidant. This may decrease the availability of coenzyme Q10 for the generation of ATP, which is required to sustain life. 3
Diagnosis of Diabetes
The normal fasting blood glucose level is less than 126 mg/dL where fasting is defined as no food intake for at least 8 hours before the blood test.
According to the American Diabetes Association, the diagnosis of diabetes can be made 3 different ways:
1. Symptoms of diabetes plus casual (unrelated to time of day or food intake) blood glucose level greater than or equal to 200 mg/dL. The classic symptoms of diabetes include excessive urination, excessive drinking, and unexplained weight loss.
OR
2. A fasting (no food intake for at least 8 hours) blood glucose level greater than or equal to 126 mg/dL.
OR
3. Blood glucose level greater than or equal to 200 mg/dL when measured over 2 hours after the patient drinks a glass of a large amount of sugar dissolved in water.
For more in depth information on the diagnosis and classification of diabetes visit http://care.diabetesjournals.org/cgi/reprint/29/suppl_1/s43.
Prevention of Diabetes
Before people develop type 2 diabetes, they almost always have “pre-diabetes” — blood glucose levels that are higher than normal but not yet high enough to be diagnosed as diabetes. A large study called the Diabetes Prevention Program study showed that people with pre-diabetes can prevent the development of type 2 diabetes by making healthy changes in their diet by reducing fat and total calorie intake and increasing their level of physical activity.
Treatment of Diabetes
Patients with diabetes should all be aware of the advantages of a healthy lifestyle including proper diet and exercise. For patients with type 1 diabetes, a healthy lifestyle is an important addition to treatment with insulin. For most patients with type 2 diabetes, such a lifestyle, which results in moderate weight loss or, at least, prevents weight gain may be enough to control blood sugar levels. When diet and exercise alone are not enough to control blood sugar levels, patients with type 2 diabetes may be treated with oral medications. Other patients with type 2 diabetes may even require insulin to control their blood sugar level. Since diabetes may be a state of increased oxidative stress, there has been interest in prescribing antioxidants to patients with diabetes.
Role of Coenzyme Q10 in the Treatment of Diabetes
Bearing in mind the role of coenzyme Q10 in ATP production, it was important to test whether dietary supplementation with coenzyme Q10 would benefit energy metabolism and ATP production in patients with in diabetes. In 120 patients with diabetes, an ATP producing enzyme that requires coenzyme Q10 to function was measured. The amount and activity of the enzyme were significantly lower than in diabetics than in non-diabetics. 4 Some oral drugs used to treat diabetes were shown to cause a further decrease in coenzyme Q10 in addition to that caused by the diabetes
The overall effect of dietary supplementation with coenzyme Q10 on diabetes has been studied. Dietary supplementation with 100 mg coenzyme Q10 twice daily in patients with diabetes significantly increased plasma coenzyme Q10 by at least 3-fold 5, 8, 13, 14 Studies of dietary supplementation with 120 mg of coenzyme Q10 per day 6 and 200 mg coenzyme Q10 per day 7 have been shown to significantly reduce blood glucose levels 6 and lower hemoglobin A1C (HbA1C), a measure of blood sugar control over 2 to 3 months. 7 Furthermore, coenzyme Q10 supplementation has been reported to reduce insulin requirements in patients with diabetes. 4
Many patients with diabetes also have elevated blood pressure, which is a significant risk factor for development of the long-term complications of diabetes described above. Coenzyme Q10 at 200 mg per day significantly lowered blood pressure in patients with diabetes. 7, 5 However, not all studies have demonstrated positive benefits of dietary supplementation with coenzyme Q10 in patients with diabetes. Two studies of dietary supplementation with coenzyme Q10 in patients with diabetes demonstrated that even though blood coenzyme Q10 levels were significantly increased, there was no measurable improvement in blood glucose levels. 8, 13
Animals are often studied to provide information to human diseases. Studies have reported that diabetic rats have mitochondrial dysfunction as shown by decreased ATP production and increased pro-oxidants in their mitochondria. 9, 11 Coenzyme Q10 treatment improved ATP production and reduced the levels of harmful anti-oxidants in these diabetic rats. 9, 10, 11 The role of bad cholesterol (LDL), harmful triglycerides, and good cholesterol (HDL) has clearly been associated with cardiovascular disease in patients with diabetes. Coenzyme Q10 treatment significantly decreased LDL and triglycerides, and increased HDL in diabetic rats. 10, 11 Finally, dietary supplementation with coenzyme Q10 was shown to increase heart coenzyme Q10 content and improve cardiac performance 12 and lower the elevated blood pressure 11 in diabetic rats.
In conclusion, the importance of coenzyme Q10 supplementation for patients with diabetes requires further study. Some doctors recommend coenzyme Q10 supplementation as a way to protect against possible effects associated with diabetes-induced depletion and for its role in cardiovascular health.
The addition of coenzyme Q10, or any other dietary supplement should never be substituted for any of your current medications to treat diabetes.
As always, consult your physician should you have any questions about the treatment of your diabetes.
References:
- Miyake Y, Shouzu A, Nishikawa M, Yonemoto T, Shimizu H, Omoto S, Hayakawa T, Inada M. Effect of treatment of 3-hydroxy-3-methylglutaryl coenzyme I reductase inhibitors on serum coenzyme Q10 in diabetic patients. Arzneimittelforschung 1999;49:324–9
- Hasegawa G, Yamamoto Y, Zhi JG, Tanino Y, Yamasaki M, Yano M, Nakajima T, Fukui M, Yoshikawa T, Nakamura N. Daily profile of plasma %CoQ10 level, a biomarker of oxidative stress, in patients with diabetes manifesting postprandial hyperglycaemia. Acta Diabetol. 2005 Dec;42(4):179-81.
- Littarru GP and Battino M. Protection against oxidative stress by chronic administration of coenzyme Q. In: Kagan VE and Quinn PJ, ed. Coenzyme Q10: Molecular mechanisms in health and disease. Boca Raton, FL: 2001:219-226.
- Kishi T, Kishi H, Watanabe T, Folkers K.. Bioenergetics in clinical medicine. XI. Studies on coenzyme Q and diabetes mellitus. J Med. 1976;7(3-4):307-21.
- Hodgson JM, Watts GF, Playford DA, Burke V, Croft KD. Coenzyme Q10 improves blood pressure and glycaemic control: a controlled trial in subjects with type 2 diabetes. Eur J Clin Nutr. 2002 Nov;56(11):1137-42.
- Singh RB, Niaz MA, Rastogi SS, Shukla PK, Thakur AS. Effect of hydrosoluble coenzyme Q10 on blood pressures and insulin resistance in hypertensive patients with coronary artery disease. J Hum Hypertens. 1999;13:203–8.
- Playford DA, Watts GF, Croft KD, Burke V. Combined effect of coenzyme Q10 and fenofibrate on forearm microcirculatory function in type 2 diabetes. Atherosclerosis. 2003 May;168(1):169-79.
- Henriksen JE, Bruun Andersen C, Hother-Nielsen O, et al. Impact of ubiquinone (coenzyme Q10) treatment on glycaemic control, insulin requirement and well-being in patients with Type 1 diabetes mellitus. Diabet. 1999;16:312–8.
- Moreira PI, Santos MS, Sena C, Nunes E, Seica R, Oliveira CR. CoQ10 therapy attenuates amyloid beta-peptide toxicity in brain mitochondria isolated from aged diabetic rats. Exp Neurol. 2005 Nov;196(1):112-9. Epub 2005 Aug 29.
- Al-Thakafy HS, Khoja SM, Al-Marzouki ZM, Zailaie MZ, Al-Marzouki KM. Alterations of erythrocyte free radical defense system, heart tissue lipid peroxidation, and lipid concentration in streptozotocin-induced diabetic rats under coenzyme Q10 supplementation. Saudi Med J. 2004 Dec;25(12):1824-30.
- Modi K, Santani DD, Goyal RK, Bhatt PA. Effect of coenzyme Q10 on catalase activity and other antioxidant parameters in streptozotocin-induced diabetic rats. Biol Trace Elem Res. 2006 Jan;109(1):25-34.
- Serizawa T, Oku J, Iizuka M, Ohya T, Ohtani Y, Sugiura S, Murakami T, Sugimoto T. Beneficial effects of coenzyme Q10 on impaired left ventricular performance in streptozotocin diabetic rats. Jpn Heart J. 1988 Mar;29(2):233-42.
- Eriksson JG, Forsen TJ, Mortensen SA, Rohde M. The effect of coenzyme Q10 administration on metabolic control in patients with type 2 diabetes mellitus. Biofactors 1999;9(2-4):315-8.
- Watts GF, Playford DA, Croft KD, Ward NC, Mori TA, Burke V. Coenzyme Q10 improves endothelial dysfunction of the brachial artery in Type II diabetes mellitus. Diabetologia 2002 Mar;45(3):420-6.