A Guide To Nutritional Supplements For Patients With Diabetes
Methylcobalamin has been proven to facilitate myelin node genesis and nerve regeneration in a double-blind study that utilized oral methylcobalamin.8 This study also showed the benefit of using methylcobalamin to regress the symptoms of diabetic neuropathy. Authors have shown that pyridoxal-5-phosphate (vitamin B6), in a dosage of 50 to 100 mg/day, decreases the glycosylation of hemoglobin.9 It is thought that glycosylated hemoglobin may be responsible for the end organ damage resulting from diabetes. Jones and Gonzalez related the usefulness of pyridoxine in the treatment of diabetic neuropathy for podiatric patients.10 It was interesting to note that the neuropathy caused by a vitamin B6 deficiency is indistinguishable from diabetic neuropathy. Much has been written in the podiatry literature on the use of alpha lipoic acid for treating peripheral neuropathy. Lipoic acid is approved in Germany for preventing and treating diabetic neuropathy. The effect may result from the medication’s antioxidant activity. Researchers have shown that lipoic acid replenishes vitamin C and glutathione, and helps recycle vitamin E. Lipoic acid may also help reduce blood glucose and the damaging glycosylation of proteins. Nagamatsu, et. al., demonstrated that lipoic acid improves nerve blood flow, reduces oxygen stress and improves distal nerve conduction in experimental diabetic neuropathy.11 Combining acetyl-L-carnitine and lipoic acid has an added benefit in the treatment of peripheral diabetic neuropathy. A recent randomized, double-blind, placebo-controlled trial with 333 patients examined the use of acetyl-L-carnitine at 1,000 mg per day intramuscularly for 10 days, followed by oral acetyl-L-carnitine at 2,000 mg per day for one year. Nerve conduction velocities dramatically increased by several fold in the acetyl-L-carnitine group compared with the placebo treatment. Acetyl-L-carnitine treatment also significantly decreased painful neuropathies by 39 percent from baseline scores. Study authors stated that acetyl-L-carnitine was a promising treatment for diabetic neuropathy.12 Several nutriceutical companies are offering a combination of acetyl-L-carnitine and alpha lipoic acid for the treatment of diabetic neuropathy. The usual oral doses are 1 to 4 g daily in divided doses. Parenteral doses were between 1 to 21.5 g daily for acetyl-L-carnitine and between 200 and 300 mg per day for lipoic acid. What You Should Know About Other Supplements • Biotin. In an animal study performed by Reddi, DeAngelis, Frank, et. al., biotin improved glucose and insulin tolerances in genetically diabetic KK gamma and KK B1 mice.13 Biotin supplementation reportedly enhances insulin sensitivity and increases the activity of the glucose kinase, the enzyme responsible for the first step in the liver’s utilization of glucose. Kinase concentrations are usually low in patients with diabetes. In Reddi’s study, 16 mg of biotin per day resulted in a significant reduction of fasting blood sugar levels and improvements in blood glucose control among people with insulin-dependent diabetes mellitus.11 Biotin doses of greater than 8 mg per day would require close observation by the attending clinician in order to make sure insulin requirements are adjusted as needed. • Chromium. Trivalent chromium, a trace element, is required for the maintenance of normal blood glucose metabolism. O’Connell demonstrated that chromium deficiency is associated with impaired glucose tolerance, which can be improved with supplementation.14 However, most individuals with diabetes are not chromium deficient. In addition to glucose control, researchers have studied the chromium supplement for its effects on weight control, control of hyperlipidemia and bone density. Trivalent chromium’s action is linked with the glucose tolerance factor (GTF) and reportedly increases the number of insulin receptors, enhancing receptor binding and facilitating insulin action. There is no RDA for chromium. Most nutritional supplements manufactured for consumption in the United States utilize at least 200 µg of chromium polynicotinate, chromium picolinate or chromium enriched yeast. • Cinnamon. Radosevich, Deas, Polansky, et.