For a number of years, the Food and Drug Administration has taken the view that the mounting zeal for whole grains has gotten ahead of what is evident from a sober look at the scientific data. Even as many in the public health community extol the nutritional and disease fighting benefits of whole grains relative to white flour, the F.D.A. has said the scientific literature allows little to be said categorically beyond the digestive benefits of fiber.

Even more recently, this position has changed little. In response to a 2012 industry petition to allow a health claim, the F.D.A. was tepid in its assessment of what the science supports today regarding whole grains and reduced risk of Type 2 diabetes. The F.D.A. acknowledged that studies provide some evidence of benefits, but said the claim of “a risk reduction relationship, while credible, falls near the lower end of the ‘limited’ category and should be described as ‘very limited’ in food labeling to avoid misleading consumers.”

It is difficult to reconcile this guarded attitude from the federal government with its enthusiastic move to upend school meal program guidelines with rigid requirements that half of all grains offered during the school week be whole grains. The inconsistent approach seems geared toward squeezing out enriched grains without fully embracing the healthfulness of whole grains and sends confounding signals to a grain-based foods industry wholly committed to meeting the needs of its entire range of customers.