Highlights of study posted Feb 2012

• 40 women with painful menstrual periods monitored for 2 months in a Random Controlled Trial
• Initially had vitamin D levels < 45 ng, were not taking vitamin D, contraceptives, or other medications
• Half took a single dose of 300,000 IU of vitamin D (average of 5,000 IU daily) 5 days before period 
  None of the women with vitamin D needed any NSAID pain killers (pain score decreased 41%)
• The other half took placebo 
  40% in placebo group needed NSAID pain killers at least once (no decrease in pain score)

Study published in Arch Intern Med. 2012;172:366-367, 367-369

The study seems to also imply that it may be inflamitory pain in general that is reduced, not just from menstrual.