Nutritional Compounds: Can They Have An Impact With Diabetic Neuropathy?
Researchers asked patients to rate eight parameters using a modification of the Wong-Baker FACES Pain Rating Scale. The eight parameters were:
• Burning pain
• Overall pain
• Perceived level of impairment of function
• Perceived level of impairment of concentration
• Perceived level of impairment of thought clarity
• Perceived level of impairment of alertness
• Perceived level of impairment of energy
The last four parameters were secondary endpoints that we assessed because an earlier pilot investigation indicated the nutritional supplements had a salutary effect on mental function. We followed the patients for three months. We conducted the pain ratings at the initiation of the study and every four weeks thereafter (see “How One Nutritional Supplement Affected Neuropathy-Related Pain And Impairment” above).
What The Study Reveals About Nutritional Compounds And Diabetic Neuropathy
We began our investigations with the assumption that while over-consumption of fats and carbohydrates contributes to diabetes, the under-consumption of critical micronutrients leads to the complications. In designing which nutrients to replenish, we assumed multiple factors are missing from the average diet in patients with diabetic neuropathy.
We then chose nutritional supplements that would address the major theories of diabetic complications. Four compounds also intersect in maintaining levels of intracellular reduced glutathione (GSH).
Cysteine availability most often limits GSH biosynthesis in vivo. One orally bioavailable cysteine source is N-acetylcysteine (NAC). The antioxidant ALA is also important in replenishing GSH. Oral ALA raises GSH levels in HIV patients and is extremely safe and well tolerated. Ascorbate conserves intracellular glutathione and probably is a redox GSH co-factor.7 Selenium is an important component of the enzyme glutathione peroxidase that works with glutathione to reduce free radicals.
Glutathione is a tripeptide intracellular thiol molecule derived from glycine, L-glutamine and L-cysteine. Intracellular reduced glutathione is an extremely important cell protectant. It is a potent antioxidant and enzyme cofactor, and its depletion by the absence of dietary precursors results in cell death. It directly quenches reactive hydroxyl free radicals, oxygen free radicals and biomolecules.8 Intracellular reduced glutathione balance is crucial to intracellular homeostasis. It stabilizes the cellular biomolecular spectrum and facilitates cellular performance and survival. Individuals with inherited deficiencies of the GSH develop hemolytic anemia, spinocerebellar degeneration and peripheral neuropathy along with other manifestations.9
Individuals with impaired glucose tolerance, including those with early hyperglycemia, have reduced blood GSH and, as discussed above, this increases the formation of AGEs.10
While over-consumption of the macronutrients, carbohydrates and fats can lead to obesity and diabetes, it is less obvious that under-consumption of key micronutrients can lead to diabetic complications including neuropathy. This investigation indicates that certain nutrients can alleviate the complaints of burning and pain that accompany diabetic neuropathy.
It would also suggest that other critical supplements like omega 3 fatty acids may be lacking from the diets of patients with diabetes and their absence could also contribute to diabetic complications. In the future, it may be beneficial to counsel those with diabetes to include key nutrients in their diet as well as watching their calories.