People who have diabetic nephropathy should avoid taking vitamin B supplements without first consulting their doctor. According to a new study published in the Journal of the American Medical Association, taking B vitamins could make this kidney condition worse – and even lead to a heart attack or stroke.
Diabetic Kidney Disease and B Vitamins
In a randomized, placebo-controlled study, 238 patients with diabetic nephropathy received a daily vitamin B supplement containing 1 milligram of vitamin B12, 25 milligrams of vitamin B6, and 2.5 milligrams of folic acid or a placebo over a period of almost three years.
When they tested the kidney function of these patients, they discovered that the group taking the B supplement had worse kidney function than the group taking the placebo. They also had double the risk of experiencing stroke, heart attack, and early death from all causes.
B vitamins lower levels of homocysteine – an amino acid that’s believed to be a marker for a higher risk of heart disease. Researchers had hoped that by giving these patients with diabetic nephropathy B vitamins they could lower their risk of heart disease and, possibly, improve their kidney function at the same time.
Although homocysteine levels were lower in the group who took the vitamin B supplement, it actually increased their risk of heart attack, stroke, and death – and reduced their kidney function. As might be expected, doctors won’t be recommending that patients with diabetic kidney disease take vitamin B supplements.
What Does Help People with Diabetic Kidney Disease?
Diabetic nephropathy eventually develops in up to forty percent of people with diabetes and can progress over the years to kidney disease that requires dialysis or transplant. Keeping blood sugars and blood pressures under control can slow down the progress of this disease significantly – which is the main focus of treatment. Medications called ACE inhibitors and ARBs are also effective for treating people with chronic kidney disease from diabetes.
The Bottom Line?
Not only are vitamin B supplements ineffective for improving kidney function and for reducing heart disease and stroke in people with diabetic nephropathy – they seem to be harmful. The best way to get B vitamins for people with diabetic nephropathy is to eat a healthy, balanced diet – and don’t take vitamin B supplements.