As a Canadian dietitian who works and lives in the United States, I like to keep up with health policy in both countries. So, I was quite interested to see that Health Canada, the governmental agency responsible for public health, is charting a new course when it comes to dietary advice, particularly in the area of sugar substitutes. It's a track that sharply diverges from the one the United States is on.
In a significant departure from the past as well as from the U.S. approach, Canada's new food and dietary guidelines, released this year, say zero-calorie or low-calorie sugar substitutes are neither necessary nor helpful. "Sugar substitutes do not need to be consumed to reduce the intake of free sugars," the guidelines say, adding that, because "there are no well-established health benefits associated with the intake of sweeteners, nutritious foods and beverages that are unsweetened should be promoted instead."
In contrast, the 2015-2020 Dietary Guidelines for Americans (DGAs), issued by the U.S. Agriculture and Health and Human Services departments, suggest sugar substitutes may have a place in helping people consume fewer calories, at least in the short term, though "questions remain about their effectiveness as a long-term weight management strategy." The guidelines neither encourage nor discourage their usage.
相比之下，美國農業部、美國衛生部和美國社會福利部門共同發布的《美國膳食指南2015版》（2015-2020 Dietary Guidelines for Americans）建議：甜味劑或能幫助人們減少卡路里攝入量，至少短時間內會做到這一點，盡管"作為一種長期體重管理策略，其有效性暫待商榷。"該指南對甜味劑持既不鼓勵也不阻止的態度。
The differences may seem subtle, but dietary guidelines in each country shape what is served at public institutions such as schools and influence the recommendations made by health-care professionals. Language matters. But before we try to explain the difference in advice, let's have a quick primer on sugar substitutes.
What are sugar substitutes?
Sugar substitutes include many categories, such as high-intensity sweeteners that are at least 100 times as sweet as sugar. They can be "artificial," such as aspartame and saccharin, or "natural," such as stevia and monk fruit. They can contain a negligible number of calories or be classified as low-calorie sweeteners, such as sugar alcohols.
In much of the research and in most policy documents, sugar substitutes are often discussed as a single category. This makes it challenging to know whether certain types are preferable.