Vitamin D supplements did not ease Colds in Duration or Frequency
(Best Syndication News) - A study from New Zealand found that vitamin D3 supplements did not reduce the frequency or severity of colds. The randomized controlled trial tested monthly dosage of 100,000 IUs of vitamin D3. The results were published in the October 3, 2012 issue of JAMA.
The researchers wanted to see if supplementation would reduce the frequency and severity of respiratory tract infections. Previous studies have suggested that a vitamin D insufficiency would make a person more vulnerable for catching a cold.
David R. Murdoch, M.D., of the University of Otago, Christchurch, New Zealand, and colleagues recruited 322 healthy adults who participated in the study between February 2010 and November 2011. Half of the participants were randomly assigned to be given 200,000 IU of vitamin D3 orally at the start of the trial, then another 200,000 IU dose one month later. Then, they were given 100,000 IU dose each month for the remainder of the study. The remaining half was given a placebo pill to take on the same schedule and method. The study lasted for 18 months.
All the participants’ 25-hydroxyvitamin D (25-OHD) levels averaged 29 ng/mL. The vitamin D group had their 25-hydroxyvitamin D (25-OHD) levels maintained at more than 48 ng/mL throughout the duration of the study.
The group taking the vitamin D had 593 upper respiratory tract infections, while the placebo group had 611 upper respiratory infections.
The difference was not statistically significant between the two groups. The average was 3.7 per person in the vitamin D group and 3.8 per person in the placebo group. The average duration of the cold - 12 days – was the same in both groups.
The researchers suggest that taking vitamin D at other dosing regimens in other populations should be tested to see if there is a benefit for reducing cold frequency and duration.
By: Marsha Quinn