Vitamin D (IMAGE) American Chemical Society Caption In a development that could help fight osteoporosis, rickets and other bone diseases, scientists are reporting an advance toward an accurate set of standards for measuring vitamin D levels in the blood. Milk (shown) is a well-recognized source of the vitamin. Credit Max Rubner Institute Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.