This blog tracks updates to the Blood Sugar 101 Web site.


Friday, January 13, 2012

Supplementing with Megadoses of Vitamin B6, B12 and Folic Acid Correlates with Double Stroke Risk and GFR Worsening

Page changed: Diabetic Kidney Disease

Added the following:

Do NOT Supplement with Higher than Normal Doses of Vitamins B6, B12 and Folic Acid

A study of people with both Type 1 and Type 2 diabetes who had been diagnosed with diabetic kidney disease found that supplementing daily with a "Single tablet of B vitamins containing folic acid (2.5 mg/d), vitamin B6 (25 mg/d), and vitamin B12 (1 mg/d)" for three years was associated with faster deterioration in GFR and a doubling of stroke risk.

Effect of B-Vitamin Therapy on Progression of Diabetic Nephropathy:A Randomized Controlled Trial. Andrew A. House et al. JAMA 2010;303(16):1603-1609. doi: 10.1001/jama.2010.490

It's important to note that the amounts used in this study were megadoses many times greater than the RDA (Recommended Daily Allowance) for each.

If you are eating a diet that does not include grains or other foods that supply natural forms of these vitamins you won't be getting them in your diet and will need to supplement, but when you do, confine your supplementation to the RDA. You can find the RDA for the B vitamins HERE.

4 comments:

Anna said...

Jenny, I looked this up on your blog after reading that grain-free diets may be deficient in certain nutrients. Looking elsewhere, it seems that B vitamins are plenty in leafy green vegetables. Are any of the B vitamins exclusively found in grains? Is supplementation in the low carb/grain free diet really necessary if leafy greens, in addition to meat, are consumed? I eat no more grains or starchy foods at all and didn't think there was anything I could be missing.

Jenny said...

Anna, You're absolutely right. Unfortunately, a lot of people who do very low carb diets neglect to eat vegetables, and they do risk problems from low B-vitamins if they do this for long enough.

timshel said...

Hi Jenny,
Thanks for the insightful info. I’ve been tracking my food intake on FitDay and having noticed that I lack Thiamine especially. I try to refrain from taking supplements because of the toxicity associated with them. Therefore I’m trying makeup for it to a small degree by taking brewers yeast for the B vitamins.
Please mention the difference of Folate Acid and Folic Acid. I’ve been reading where there’s a difference and that Folic Acid is said to be a copycat synthetic vitamin detrimental to health.

timshel said...

Hi Jenny,
Thanks for the insightful info. I’ve been tracking my food intake on FitDay and having noticed that I lack Thiamine especially. I try to refrain from taking supplements because of the toxicity associated with them. Therefore I’m trying makeup for it to a small degree by taking brewers yeast for the B vitamins.
Please mention the difference of Folate Acid and Folic Acid. I’ve been reading where there’s a difference and that Folic Acid is said to be a copycat synthetic vitamin detrimental to health.