Souring on sweetener?

Hey there, time traveller!
This article was published 14/05/2019 (2635 days ago), so information in it may no longer be current.

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 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 U.S.

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 not necessary or 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 usage.

The differences may seem subtle, but dietary guidelines in each country are used to shape what is served at public institutions such as schools and are what many health-care professionals base their recommendations on. Language matters. But before we try to explain the difference in advice, let’s have a quick primer on sugar substitutes.

Sugar substitutes include many categories, such as high-intensity sweeteners 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 rather than a heterogenous group of compounds. This makes it challenging to know whether certain types are preferable.

Most concern seems to focus on artificial sweeteners. Six are approved by the U.S. Food and Drug Administration as ingredients in foods and drinks and as table sweeteners people can add themselves. You’ll find artificial sweeteners in a range of foods and drinks, including light yogurt, diet sodas, protein bars and chewing gum, as well as baked goods and frozen desserts. Carbonated drinks are the top source of artificial sweeteners in the American diet.

Research suggests stevia and monk fruit, the natural sugar substitutes, are safe for human consumption, though it’s not clear they lead to weight loss. There has been conflicting research, however, about the safety of artificial sweeteners. Some studies have suggested artificial sweeteners could increase the risk of Type 2 diabetes, heart disease, kidney disease and cancer, and may have a negative influence on the microbiome and mental health.

For example, research based on data from 37,716 men from the Health Professional’s Follow-up study and 80,647 women from the Nurses’ Health study published in Circulation last month found consuming artificially sweetened beverages is associated with a greater risk of death as well as death from heart disease. The risk was found specifically for women consuming four or more servings of artificially sweetened beverages a day. The authors say this finding needs to be confirmed by future research, but it does raise questions about whether artificial sweeteners are necessary — or should be recommended at all.

As for the U.S. contention sugar substitutes might help people cut back on calories and sugar to improve their health or lose weight — that seems doubtful. A review by the non-profit research foundation Cochrane, conducted for the World Health Organization, examined 56 studies into the effects of sugar substitutes on health. It found there is no evidence sugar substitutes provide any benefit — and may even have some risks. An analysis of U.S. dietary intake from 2003 to 2004 shows people tend to add artificial sweeteners to their diets rather than replacing sugary foods and beverages with them.

The same seems to be true for children. This month, research published in the Pediatric Obesity journal revealed in U.S. children, drinking artificially sweetened beverages is associated with consuming more calories and sugar.

U.S. and Canadian health officials are looking at the same research and have populations with similar health issues. So, why the difference in guidelines regarding sugar substitutes?

The new Canadian approach seems to be if a food or beverage doesn’t have a demonstrated health benefit, it doesn’t belong. Their 2019 guidelines suggest people’s tastebuds will adapt to less-sweet tastes when they reduce their consumption of sweetened foods and beverages — and using high-intensity sweeteners delays that process.

This is a marked change from Canada’s last dietary guidelines, released in 2007, which advised the general population to consume sugar substitutes in moderation and to cut back on them if they noticed any digestive symptoms such as gas and bloating.

The new Canadian recommendations may seem tougher, but I see them as being clearer and something for people to aspire to. The U.S. view seems to be focused on encouraging health behaviours thought to be more achievable.

Alice H. Lichtenstein, a professor of nutrition science and policy at Tufts University and member of the 2015-2020 DGA committee, seems skeptical of an all-or-nothing approach to sugar substitutes. She expressed her stance in an editorial in Circulation, responding to the study that said consuming artificially sweetened beverages is associated with a greater risk of death. “To a certain extent, as a community, we can take the high road about beverage recommendations: drink water (or flavoured water) in place of (sugar-sweetened beverages). However, continuing this simple approach would be disingenuous because we know that it has not worked well in the past and there is little reason to expect that it will work well in the future.”

A 2018 advisory from the American Heart Association also takes a more middle-ground approach to sugar substitutes than Canada’s, stating they can play a role in helping people to reduce the amount of sugar-sweetened beverages they’re drinking. The advisory also says beverages containing low-calorie sweeteners could be especially useful for people who are used to sweetness and find water unappealing at first.

I found one hint the viewpoint in the United States might be changing. Last month, the American Diabetes Association released a nutrition consensus report that recommends water replace sugar-sweetened beverages. If sugar substitutes are used, the report says, people should receive nutrition counselling to help them avoid replacing the calories and carbohydrates with food.

The authors also note any proposed advantages to sugar substitutes haven’t been proven, and there could be potential adverse effects.

Brissette is a registered dietitian, nutrition writer, TV contributor and president of 80twentynutrition.com.

— Washington Post