Vitamin levels up five years after gastric bypass

Last Updated: 2015-07-15

By Rob Goodier

NEW YORK (Reuters Health) - In a five-year follow-up study of Roux-en-Y gastric bypass patients, researchers found the levels of certain vitamins increased while others remained the same as before surgery.

The increases may be because patients took their supplements and ate better, but also because their vitamin concentrations before surgery may have been poor, lead author Dr. Eirik Aaseth from Oslo University Hospital in Norway told Reuters Health by email.

Past studies have found an elevated risk of vitamin deficiency following gastric bypass, and these new findings should encourage patients to take their supplements, Dr. Aaseth said.

The researchers retrospectively followed 441 patients through medical records and estimated changes in vitamin concentrations using linear mixed models that adjusted for age and sex. Their results were published online June 17 in the European Journal of Clinical Nutrition.

Before surgery, 1%-9% of the patients took multivitamins. One year later, 79%-84% of patients did so, and by five years 52%-83% took the supplements.

At the five-year follow-up, patients had significant increases in folic acid (from 15.9 nmol/l before surgery to 23.1 nmol/l), vitamins B-6 (from 33.1 to 43.3 nmol/l), vitamin B-12 (from 364 to 547 pmol/l), vitamin C (from 46 to 59.7 mmol/l) and vitamin A (from 1.68 to 1.80 mcmol/l).

Concentrations of thiamine, 25-hydroxyvitamin D and lipid-adjusted vitamin E were not changed compared to levels before surgery.

Dr. Aaseth stressed that some patients will not have increased vitamin concentrations. "Identify at-risk individuals for vitamin deficiency, e.g. persistent vomiting the first weeks after surgery - thiamine deficiency," he advised.

SOURCE: http://bit.ly/1J0rwoP

Eur J Clin Nutr 2015.