Introduction
Diabetes mellitus is one of the most common chronic, progressive diseases characterized by chronically elevated blood sugar levels, insulin resistance, and several complications. The severity of diabetic complications varies depending on the course of the disease, its duration, and the degree of hyperglycemia, or high blood pressure. Diabetic complications can be either macrovascular when coronary arteries, peripheral arteries, and cerebral arteries are affected, or microvascular, when smaller blood vessels are affected, primarily leading to diabetic neuropathy, nephropathy, and retinopathy, cataracts, and glaucoma. The major mechanism behind diabetic complications is chronically elevated blood glucose levels, which damages blood vessels by negatively affecting the structure of proteins by forming so-called advanced glycation products. This increases oxidative stress, disrupts the integrity of cellular barrier and communication between the cells, and promotes inflammation. Depending on the location, poor vascular health leads to kidney damage, poor vision, pain changed sensitivity of limbs, or even foot ulcers.
Nutrients that can help
Certain nutrients can help reduce diabetic complications. Most of them have antioxidant and anti-inflammatory activity, helping reduce inflammation, boost vascular health,and improve nerve conductivity.
Alpha-Lipoic Acid
Alpha-lipoic acid is an antioxidant compound naturally produced in the body, but can also be obtained via dietary sources such as red meat, organ meats, spinach, broccoli, carrots, and beets. Alpha-lipoic acid is one of the most commonly used supplements for peripheral neuropathy in diabetic patients, which is characterized by diminished sensitivity in the limbs, numbness, muscle weakness, and muscle twitching. A meta-analysis of 10 clinical studies in adults with diabetic polyneuropathy shows that taking alpha-lipoic acid daily for up to 2 years reduces the incidence, severity, and frequency of sensory symptoms and improves measures of impairment and neurological disability.
Berberine
Berberine is a bioactive plant compound with a long history of use in traditional Chinese medicine. Berberine is one of the most effective and the most frequently used supplements for lowering blood glucose and improving metabolic health in individuals with type 2 diabetes. Berberine is as effective as metformin, which is why it’s often called a metformin alternative or metformin substitute. Therefore, berberine is crucial for reducing chronic hyperglycemia, thus reducing damage to blood vessels. Some animal experiments have shown that berberine also has the potential to help with peripheral neuropathy and nephropathy, or kidney damage. In regards to nephropathy, berberine reduces inflammation and oxidative stress while improving markers of renal function.
Pycnogenol
Pycnogenol is a patented extract of maritime pine. It’s well known for its high anthocyanin content, which makes it beneficial for a wide range of chronic health conditions that are associated with inflammation and oxidative stress. Pycnogenol seems to have a glucose-lowering effect, which is thought due to its strong antioxidant activity. It also improves endothelial function, thus supporting cardiovascular health and fighting diabetic complications. Patients with diminished kidney function may also benefit from Pycnogenol as it has been shown to improve kidney blood flow and function, also lowering blood pressure. Taking Pycnogenol may also slow or prevent further deterioration of retinal function when compared with no treatment. Overall, its unique, multifaceted properties allow Pycnogenol to be successfully used for reducing diabetic complications.
Omega-3 fatty acids
Omega-3 fatty acids are often touted as a to-go supplement for a variety of health issues and for a good reason. The two main omega-3 fatty acids, EPA and DHA, are constituents of the cellular membranes, so cellular health and optimal functioning of cell-to-cell communications largely depend on sufficient omega-3 intake. In particular, DHA is highly concentrated in the retinal cell membranes. In regards to diabetic complications, omega-3 fats have been primarily studied for preventing or reducing retinopathy due to their neuroprotective function, which helps alleviate nerve damage. In one study, supplementation with polyunsaturated fatty acids increased the fiber length (+23%), fiber density (+13%), and branch density (+58%). The other study found that circulating DHA and DHA and EPA levels combined are associated with a lower incidence and severity of diabetic retinopathy. This means that higher omega-3 fatty acids intake may prevent the development of diabetic retinopathy.
Coenzyme Q10
Coenzyme Q10 is a fat-soluble compound naturally found in the human body. The highest concentrations of CoQ10 are in the heart, liver, kidneys, and pancreas. There are two physiological forms of CoQ10, ubiquinone, and ubiquinol, which are available as supplements.
Coenzyme Q10 supplementation significantly improves nerve conduction and symptoms of neuropathic pain when compared with placebo in diabetic patients with polyneuropathy. The other study found that CoQ10 supplementation reduces pain severity and sleep interference due to pain; almost half of the participants had their pain reduced by at least 50%. Many of the therapeutic effects of coenzyme Q10 are primarily attributed to its antioxidant effects. It also exerts a significant anti-inflammatory effect by lowering inflammatory biomarkers.
Capsicum
Capsicum is a plant genus, which includes various sweet peppers and chili peppers. In medicine, capsicum is used as a source of capsaicin and other capsaicinoids. Capsaicin, the active constituent of capsicum, is used topically for various disorders involving chronic pain, including diabetic neuropathy. Upon application, it binds to the pain receptors in the skin and can also cause widening of blood vessels (vasodilation). It appears that the degree of vasodilation caused by capsaicin positively correlates with the degree of pain reduction. Capsaicinoids may also act on other neurological mechanisms by reducing the sensitivity of pain receptors. A meta-analysis of the available clinical research for diabetic peripheral neuropathy found that one-time application of a specific patch containing 8% capsaicin is equally effective to prescription medications such as duloxetine, pregabalin, and gabapentin in producing a 30% or 50% pain reduction.
B vitamins
B vitamins, especially B1, B2, B6, B9, and B12, are frequently used in combination treatment of diabetic complications. Not only do B vitamins play a central role in healthy glucose metabolism and may prevent or alleviate some diabetic complications, but they are also crucial for compensating the nutrient-depleting effects of antidiabetic drugs such as metformin. Diabetic patients are often deficient in B vitamins, particularly B1 and B6, possibly due to their accelerated use in oxidative stress and inflammation as well as insufficient dietary intake. Benfotiamine, a fat-soluble derivative of vitamin B1, has been studied for diabetic neuropathy. It can reduce pain and improve neuropathy score and nerve conduction velocity. Overall, B complex, which includes thiamine, supplementation may have positive effects on the symptoms of diabetic neuropathy. Benfotiamine may also be helpful for diabetic nephropathy, especially during an early disease stage, reducing kidney damage and loss of proteins in the urine. Lastly, benfotiamine may have a protective effect on the development of diabetic retinopathy, according to an experimental study.
Palmitoylethanolamide (PEA)
Palmitoylethanolamide (PEA) is a fatty acid amide. The dietary sources of PEA include egg yolk and plant fats, such as soy lecithin and ground peanuts. PEA is also made naturally by the body in response to stress and pain. Preliminary clinical research in adults with diabetic neuropathy shows that taking a specific type of micronized PEA reduces neuropathic pain when compared with baseline. The analgesic effects of PEA are likely due to its local anti-inflammatory effects at the site of nerve injury. PEA is found naturally in ocular tissue. It is thought that PEA plays a role in the protection of ocular tissue, such as the retina, which might be helpful in diabetic retinopathy. The anti-inflammatory effects of PEA likely protect the retina against oxidative stress and inflammatory cytokines. Clinical research shows that possible benefits of PEA regarding eye health might be related to improved peripheral endothelial function.
Curcumin
Curcumin is a major component of turmeric and one of the most studied natural anti-inflammatory aids. It is used for a wide range of chronic health conditions, especially those accompanied by chronic pain. Curcumin supplementation can have a positive effect on diabetic complications through several mechanisms. Due to its antioxidant properties, curcumin can destroy oxygen radicals directly and by inducing antioxidant responses mediated by the body’s enzymes. Curcumin also has endothelial-protecting properties, which improve blood flow, thus aiding diabetic microvascular complications. One study found a reduction of polyneuropathy symptoms in patients with diabetes mellitus following supplementation with nano curcumin. The positive effect seen was mainly attributed to the ability of curcumin to lower blood glucose and HbA1c levels. A study of the effectiveness of turmeric in patients with diabetic nephropathy found that it can lower inflammation and reduce proteinuria, which is a strong indicator of the protective function of turmeric on kidneys.
Acetyl-L-Carnitine
Acetyl-L-carnitine (ALCAR) is an ester of the amino acid derivative, L-carnitine, which is naturally found in the body. L-carnitine is synthesized in the human brain, liver, and kidneys from the amino acids lysine and methionine. There have been several studies assessing the effect of ALCAR for managing diabetic neuropathy. A meta-analysis shows that taking 2-3 grams of ALCAR daily for up to 12 months modestly reduces pain scores by about 15 points on a 100-point visual analog scale, while lower doses of 1.5 grams daily improve pain scores to a similar extent as placebo. Some research suggests that ALCAR seems to increase nerve fibers, regenerate nerve fiber clusters, and improve vibratory sensations. However, lower dosages might not be effective.
Conclusion
Diabetic complications negatively impact the quality of life and significantly increase mortality rates. Prevention and timely treatment are crucial for stopping or reversing diabetic complications. Combined with dietary and lifestyle changes, supplementation with some nutrients can be a game changer. B vitamins, curcumin, berberine, alpha-lipoic acid, and other natural compounds mentioned in this article have a strong evidence base, which confirms their benefits for the prevention and management of diabetic complications.
As always, we recommend you consult your doctor before taking any supplements, especially if you already take prescription medications, to avoid negative side effects and interactions.
If you enjoyed this article, you may also want to read this article on Why Is My Blood Sugar High in the Morning? Causes and Treatment Tips.
*This information is not intended to serve as a substitute for professional medical or dietary advice tailored to individual needs.
Po-Chang Hsu, M.D., received his medical doctorate from Tufts University School of Medicine in Boston. During his medical school training, Dr. Hsu worked with various patients, including adult and pediatric patients with acute and chronic conditions. Dr. Hsu’s interests include neurology, psychiatry, pediatrics, and sleep medicine.
Before medical school, Dr. Hsu finished a master’s degree at Harvard University and wrote a thesis on neuroimaging in schizophrenia patients at Brigham and Women’s Hospital, a Harvard Medical School-affiliated hospital. Dr. Hsu was also a part of the 2008 NASA Phoenix Lander Mission team, which sent a robotic spacecraft to the North polar region of Mars. Dr. Hsu also had research experience on neuroimaging in neonates at Boston Children’s Hospital, another Harvard Medical School-affiliated Hospital.
Since graduating from medical school, Dr. Hsu has worked as a full-time medical writer and consultant. In addition, he has experience writing and ghostwriting books and articles for physicians and health technology start-up companies. Dr. Hsu believes good communication between healthcare providers and patients creates the best results.
Publications
-Peer Reviewed Journal Article:
Kounaves, S.P., Hecht, M.H., West, S.J., Morookian, J.-M., Young, S.M.M., Quinn, R., Grunthaner, P., Wen, X., Weilert, M., Cable, C.A., Fisher, A., Gospodinova, K., Kapit, J., Stroble, S., Hsu, P.-C., Clark, B.C., Ming, D.W. and Smith, P.H. The MECA wet chemistry laboratory on the 2007 phoenix mars scout Lander. Journal of Geophysical Research. 2009, Mar; 114(E3): 10.1029/2008je003084.
-Poster Presentation:
2011 Harvard Psychiatry Mysell Poster Session; Boston, MA
Hsu, P.C., Rathi, Y., Eckbo, R., Nestor, P., Niznikiewicz, M., Thompson, E., Kubicki, M., Shenton, M.E. (March, 2011). Two-Tensor Diffusion Tensor Imaging of Acoustic Radiations in Schizophrenia