Vitamin B12 Deficiency

Diabetes and its sequelae 

Diabetes is a life-long condition that results from the inability of the body to control levels of glucose in the blood. As a result, blood glucose levels rise uncontrollably. Many of the complications of diabetes arise from the inability to successfully maintain normal glucose levels. Apart from the obvious problem of glucose control, other complications of diabetes can be  the development of neuritis, which is an inflammation of a nerve or nerves. This inflammation usually manifests itself in pain in the area of affliction. It also may result in paresthesia (pins and needles), paresia (weakness), hypoesthesia (numbness), paralysis, wasting and disappearance of reflexes. In diseases such as Diabetes, one or many nerves can be affected. If neuritis is left untreated it can lead to permanent nerve damage and debilitation. The continued high level of glucose can also lead to complication such as heart disease and blindness. Type II diabetes has recently been linked to inflammation in fat cells.

Vitamin B₁₂ Deficiency, Metformin Use and Diabetes 

Vitamin B₁₂ helps to maintain healthy nerve cells and blood cells. Several studies have have shown that vitamin B₁₂ deficiency can lead to several conditions in diabetic persons. The use of Metformin (brand names Glucophage, Glucophage XR, Fortamet, Riomet, Glumetza, and others) early in the treatment of type II diabetes leads to a steady reduction in serum vitamin B₁₂ ultimately leading to symptoms of vitamin B₁₂ deficiency. The extent of vitamin B₁₂ reduction is dependent upon the dose and length of time that the person uses the drug. The development of sub-clinical deficiency also depends very much on the starting level of vitamin B₁₂ in the diabetic person. The subsequent deficiency in vitamin B₁₂ can in turn lead to an increase in serum homocysteine levels. Increases in the level of homocysteine has been shown to correlate with increases in cardiovascular disease, diabetic neuritis and it has now been shown that it is an independent risk factor  for the development of diabetic retinopathy.   Patients who have been on Metformin™ medication for some time often exhibit many of the symptoms of vitamin B₁₂ deficiency, including paleness, shortness of breath, fatigue, weakness, numbness and tingling of hands and feet, and signs of cognitive impairment, such as short term memory loss. and reduced cognitive function (1-41). Administration of vitamin B₁₂ can reduce serum levels of serum homocysteine, which will in turn reduce pain, initiate repair to the myelin sheaths, and promote regeneration of the nerve cells in conditions such as diabetic neuropathy and diabetic retinopathy. Vitamin B₁₂ supplementation to treat vitamin B₁₂ deficiency can also reduce the levels of methyl malonic acid (MMA) in serum. MMA is a by-product of insufficient utilization of fatty acids and amino acids for energy production. Thus, supplementation with Adenosylcobalamin (a particular form of the vitamin) can help to regain energy stores in diabetic patients who are taking metformin, who often have continued feelings of exhaustion. High doses of vitamin B₁₂ have been shown reduce the inflammatory response seen in many conditions, such as neuritis and as such may be of benefit to persons with diabetes. .

Treatment of vitamin B₁₂ deficiency in the Diabetic Patient 

Once a person is showing signs of vitamin B₁₂ deficiency it is almost impossible to provide enough vitamin B₁₂ with oral supplements to restore both the serum levels of vitamin B₁₂ and the levels in the central spinal fluid and the brain. It has recently become apparent that oral supplementation with vitamin B₁₂ does not provide enough vitamin B₁₂ to overcome vitamin B₁₂ deficiency due to the limited uptake capacity of the intestine for vitamin B_12, hence there is a requirement for higher initial doses of vitamin B₁₂ to be supplied either by injection or via the topical vitamin B₁₂ formulation.  Recently a topical form of vitamin B₁₂ has been developed that is a specially formulated preparation that is an easy to apply, needle-free delivery system suitable for application to the skin of the Diabetes patient. This pain-free form of delivery greatly increases the patient comfort experienced during the administration of the medication and allows for self-medication without the need for medical staff or any special training. In addition, the topical formulation is particularly suited to diabetes patients who are on Metformin™ medication, as these patients continue to have poor absorption of the vitamin from the intestine. Such patients generally cannot absorb adequate amounts of vitamin B₁₂ from oral supplements.. 

Further Information on Neuritis, Peripheral Neuropathy and Vitamin B₁₂ Deficiency, Metformin use and diabetes

Check out the following sites for further information:

http://www.livestrong.com/article/291509-peripheral-neuropathy-and-vitamin-b12/

http://peripheralneuropathycenter.uchicago.edu/learnaboutpn/typesofpn/systemic/nutrition.shtml

http://diabetes.webmd.com/news/20090608/metformin-linked-to-b12-deficiency

http://diabetesinformationhub.com/DiabetesNutrition_VitaminB12Deficiency.php

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42. Mastroianni etal. Monitoring vitamin B12 in women treated with Metformin for primary prevention of breast cancer and age-related chronic diseases. Nutrients, 2019 PMC6567263
     

Scientific publications on vitamin B₁₂ and neuritis can be found at the following link