The US Food and Drug Administration now allows bakers to use special yeast that boosts vitamin D levels in bread to as high as 400 international units (IU) per 100 grams (about three slices of bread).
The previous limit was 90 IU. The recommended daily amount for vitamin D is 600 IU to 800 IU. Best: Look for breads labeled "High," "Rich in" or "Excellent Source of" vitamin D.
* Source: Tufts University Health & Nutrition Letter. www.TuftsHealthLetter.com
** Article taken from Bottom Line/Personal newsletter, Volume 34, Number 7, April 1, 2013.