Is there currently a difference between the meanings of the terms
"sugarless" and "sugarfree"?  Has there ever been a difference between
these two words?

Howdy agerard-ga,

Currently there is no difference between the terms "sugarless" and "sugar
free" at least as far as the United States Food and Drug Administration
(FDA) are concerned.
http://www.cfsan.fda.gov/~lrd/cf101-60.html

"Sec. 101.60  Nutrient content claims for the calorie content of foods.
...
Sugar content claims--(1) Use of terms such as 'sugar free' ...
'sugarless' ... 'dietarily insignificant source of sugar.' Consumers
may reasonably be expected to regard terms that represent that the food
contains no sugars or sweeteners ... as indicating a product which is low
in calories or significantly reduced in calories."

Canada agrees with the above definition.
http://laws.justice.gc.ca/en/F-27/C.R.C.-c.870/text.html

"Free of sugars

The food

(a) contains less than 0.5 g of sugars per reference amount and serving
of stated size ...

'sugar-free' ... 'sugarless'"

I have found no evidence that there ever has been any difference between
the terms.  Even though sugarless products started coming into their own
in the 1950s, the trademark use of "sugarless" doesn't show up until 1964,
with "sugar free" waiting until 1973 to be used in a trademark.

If you need any clarification, please feel free to ask.


Search strategy:

Google search on: "sugar free" sugarless definition changed OR revised
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Google search on: "sugar free" sugarless food drug definition
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Looking Forward, denco-ga - Google Answers Researcher

It would appear to me that it is six of this and half a dozen of that.