Another overlooked need for B vitamins

In a new study from Australia, researchers found an “association” between the diabetes drug Metformin and cognitive impairment. Specifically, they discovered that Type II diabetics who take Metformin run a greater risk of developing cognitive impairment.

How can this be?

As I’ve often reported, hundreds of studies over the past 25 years have always shown that Metformin is a safe and effective drug for lowering blood sugar. And in fact, one recent study showed that it helps lower a Type II diabetic’s risk for cognitive impairment.

Obviously, there’s something else going on here to turn up these troubling results. So, let’s take a closer look at the study to find out…

For this study, researchers looked at data gathered from several sources throughout Australia. The final analysis included 1,354 patients. On average, the patients were 74 years old.

Overall, patients with Type II diabetes had lower cognitive measures than those without diabetes, with an odds ratio of 1.51 (P = 0.03). That means diabetics were 50 percent more likely to suffer some cognitive impairment compared to non-diabetics. And this makes sense. As I’ve often reported, high blood sugar itself appears to cause cognitive impairment. I call this condition “Type III diabetes.”

Then, the researchers looked specifically at diabetics who took Metformin. They found that men and women who took the drug had worse cognitive measures. With an odds ratio of 2.23. In other words, these patients had more than double the rate of dementia compared to diabetics who didn’t take Metformin.

However, the actual results are not as dramatic as the statistics seem to show.

Men and women who took Metformin scored 22.8. And men and women who didn’t take Metformin scored 24.7. So, less than two points off a 25-point average is not so alarming.

Still, it is important to understand these findings. And it turns out that we can readily explain these observations. We can also prevent them, with a little basic knowledge of nutrition.

You see, since the 1970s, clinicians and scientists have been aware that men and women who take Metformin often wind up with low vitamin B12 levels. Experts believe Metformin may interact with a receptor in the lower small intestine. And this inhibits the uptake of vitamin B12 somewhat.

As you know, absorbing adequate vitamin B from the diet requires healthy stomach and intestinal functions. And many factors can potentially interfere with or inhibit this absorption process.

So now, let’s look again at the new Australian analysis…

Among patients with diabetes, the cognitive function measures were lower among those who had low serum vitamin B12 levels (less than 250 pmol/L). So, low vitamin B12 may have actually caused the low cognitive function. In fact, we have known for decades that B vitamins are critical for healthy brain and nervous tissue. In fact, in Europe, they call B vitamins “neurovitamins.”

In light of what we know about Metformin and intestinal malabsorption, many patients who take the drug may not receive adequate vitamin B12. Even if they follow a well-balanced diet.

In addition, other things can contribute to low B12. Including a vegetarian diet, gastro-intestinal surgery, and use of drugs that suppress stomach acid.

I would venture to say that many doctors mistakenly diagnose their diabetic patients who use Metformin with “diabetic neuropathy.” But they really just have low B12. And it’s easy to correct this condition if it hasn’t gone on for too long.

Amazingly enough, despite Metformin’s long market history, we don’t have any guidelines in place about monitoring or supplementing with B vitamins for patients who take the drug.

Of course, the RDAs aren’t sufficient to deal with these issues. They won’t help you reverse the potential effects of Metformin. Nor will they reduce the risk of cognitive decline in later life.

Bottom line?

If you have Type II diabetes and take Metformin, you should absolutely supplement with a good vitamin B complex. It will contain all of the vitamins in the B family. Look for one that gives you a daily dose that contains 5 to 10 mg of B6, 20 to 40 micrograms of B12, and 800 to 1600 micrograms of folate. I’ll go into more detail on doses, forms and sources of B vitamins in an upcoming issue of my Insiders’ Cures newsletter. If you are not yet a subscriber, now is the perfect time to get started.

And even if you don’t take Metformin, vitamin B should be part of any natural approach to good health as you get older.

It would be great if we could reverse every dangerous drug side effect with good nutrition. Fortunately, we do have a few good examples. Take CoQ10 and statin drugs, for example. And now, B12 and Metformin.

Unfortunately, most physicians don’t know about them. You first have to know something about human nutrition. And that simply isn’t taught in medical schools. And the drug reps certainly aren’t informed or talking about it.

Although, if Section 2706 of the Affordable Care Act avoids the chopping block, you may have an easier time finding a nutritionally minded practitioner…and your insurance will even help cover the visit.


1.“Increased Risk of Cognitive Impairment in Patients With Diabetes Is Associated With Metformin,” Diabetes Care, September 5, 2013, published online ahead of print