Taking Vitamin D Supplements with Meals
Dr. Michael Greger’s Latest in Clinical Nutrition 6 is now available! In it, he mentions a study about taking vitamin D with meals. I’ve wondered if doing this would help people whose vitamin D levels seem to be resistant to supplementation and so I tracked down the study and updated the VeganHealth.org article, Bones, Vitamin D, and Calcium:
Because vitamin D is a fat soluble vitamin, taking vitamin D supplements with foods that contain fat might increase absorption.
A 2010 study explored this (1). A group of people diagnosed with vitamin D deficiency had been prescribed supplements (some D2 and some D3) and were being monitored by the Cleveland Clinic Foundation Bone Clinic. Some of these patients’ vitamin D levels had not increased to desired levels. Patients with stubborn vitamin D levels were then instructed to take the vitamin D with meals. After 2 to 3 months of taking with meals, the average vitamin D level went from 30 to 47 ng/ml (75 to 117 nmol/l).
This study had no control group, so it is not clear that the vitamin D levels increased due to taking with meals. It could have been simply because their levels took longer to respond to supplements or because they were exposed to more sunlight during the meal period (the time of year studied was not reported). It should also be noted that even though these subjects’ vitamin D levels were more stubborn than other patients, their levels at the beginning of the study were well above those recommended by the Institute of Medicine (16-20 ng/ml or 40-50 nmol/l) the stubborn levels might have been a result of the body regulating vitamin D once it had reached an ideal level rather than an inability to absorb it.
1. Mulligan GB, Licata A. Taking vitamin D with the largest meal improves absorption and results in higher serum levels of 25-hydroxyvitamin D. J Bone Miner Res. 2010 Apr;25(4):928-30. Link