People with type 2 diabetes often develop a painful nerve disorder called diabetic neuropathy. People with this condition may experience numbness, tingling, burning or pain in their hands or feet. They may have trouble finding an effective treatment. However, a preliminary study shows that vitamin B12 supplements can reduce the nerve pain of diabetes (Nutrients, Jan. 27, 2021).
Treating the Nerve Pain of Diabetes:
A randomized, placebo-controlled trial of 90 people found that a year of vitamin B12 supplementation improved symptoms and quality of life. All the participants had type 2 diabetes and took metformin to keep their blood sugar under control. They had low vitamin B12 levels at the start of the study, perhaps partly as an effect of metformin. As useful as it is, this drug is known to reduce vitamin B12 absorption. People with low levels of vitamin B12 appear more likely to experience nerve pain (Endocrine Connections, Oct. 1, 2019).
Studying Vitamin B12 Supplements:
During the course of the trial patients took 1 milligram (1,000 micrograms) of methylcobalamin (vitamin B12) or placebo daily. Methylcobalamin is the preferred form of vitamin B12 for oral supplementation. The authors report that at the end of the year, patients taking vitamin B12 had improvements in the nerve pain of diabetes as well as in neurophysiological functioning and quality of life. Volunteers in the control group deteriorated significantly on the tests used to take these measurements. Consequently, people with type 2 diabetes should ask their doctors about taking methylcobalamin along with metformin to reduce or prevent the nerve pain of diabetes.
Pills or Shots for the Nerve Pain of Diabetes?
Over the last decade or so, doctors have shifted away from the practice of administering vitamin B12 through an injection given monthly or every six weeks to prescribing high-dose tablets such as those used in the study under discussion. A more recent study used a special ophthalmic technique (corneal confocal microscopy) to compare the effectiveness of tablets and injections (Scientific Reports, July 19, 2021). Over eight weeks, the scientists administered either 1.5 mg methylcobalamin daily as tablets or injections of 0.5 mg thrice weekly to people with diabetic peripheral neuropathy. Injections were more effective.
Other Supplements to Help Ease Neuropathy:
Vitamin B12 is not the only supplement that may be useful for people suffering from diabetic nerve pain. Some doctors recommend alpha-lipoic acid to treat this problem (Expert Opinion on Pharmacotherapy, Dec. 2014). Researchers have also reported greater benefit from a combination of alpha-lipoic acid and vitamin B complex (including vitamin B12) than from either alone (Current Health Sciences Journal, Apr-Jun 2020). Another supplement that has been recommended is a synthetic form of vitamin B1 called benfotiamine (Minerva Medica, Oct. 2017). Physicians suggest starting with 300 mg twice daily, then dropping to 150 mg twice daily for maintenance.