Gregg Easterbrook, ESPN's Tuesday Morning Quarterback, delights as usual with his analysis of Oregon's "blur offense" and the NFL's sweet and sour plays of the week, not to mention the Cheerleader of the week. His commentary on English grammar? Not so much.
TMQ: Grammar Snob: The expression "healthy food" has become widespread, used where "healthful food" would be correct. Food can't be "healthy." Food, in most cases, is dead.
Here, he's being not so much a snob as falling prey to scrupulosity—seeing a sin where there is none. The English language is not as rule-bound as he thinks it is. Yes, there are language scolds who insist on the distinction he makes here. But their narrow definition of "healthy" is not historically supported. "Healthful" has always been among the secondary meanings of "healthy."
What's more, the expression "healthy food" has not "become widespread"; it always was widespread. Google Books turns up, for the 19th century, 5,660 instances of "healthy food" and 3,850 of "healthful food." For the 20th century the figures are 21,500 for "healthy food"; 11,000 for "healthful."
Here is the "Botanalogia Universalis Hibernica: or a General Irish Herbal" a 1735 reference work:
POTATOES Hib. Potaty, or Pholy, Lat. Poma terrestria. They are a very nourishing healthy food, which appears by the strong heat, and robust Constitutions, of a vast number of the Natives who are almost intirely [sic] supported by them. [emphasis added]
And here is the usage note from the American Heritage Dictionary:
The distinction in meaning between healthy ("possessing good health") and healthful ("conducive to good health") was ascribed to the two terms only as late as the 1880s. This distinction, though tenaciously supported by some critics, is belied by citational evidence—healthy has been used to mean "healthful" since the 16th century. Use of healthy in this sense is to be found in the works of many distinguished writers, with this example from John Locke being typical: "Gardening . . . and working in wood, are fit and healthy recreations for a man of study or business." Therefore, both healthy and healthful are correct in these contexts: a healthy climate, a healthful climate; a healthful diet, a healthy diet.