Today, artificial sweeteners and other sugar substitutes have become ubiquitous in food, showing up in a slew of products including diet sodas, sliced bread and low-sugar yogurts — not to mention your morning coffee. But questions about sugar substitutes have been swirling for decades, with scientists and public health officials suggesting they might come with certain health risks of their own.

The research on how sugar substitutes affect our bodies is preliminary, complex and sometimes contradictory. “They haven’t been studied as much as they should be in humans,” said Dr Dariush Mozaffarian, a cardiologist and director of the Food is Medicine Institute at Tufts University in the United States. That leaves us with many questions about how to weigh their potential benefits and risks. Here’s what we know.

What is a sugar substitute?

The term includes a range of substances that taste sweet but lack the calories found in sugar. They are sometimes hundreds to tens of thousands of times sweeter than sugar, so a little goes a long way.

Sugar substitutes are grouped according to how they’re made. Artificial sweeteners are synthetic food additives that are 200 to 20,000 times sweeter than table sugar, according to the US Food and Drug Administration. Since the 1970s, the agency has approved six of them: aspartame, sucralose, saccharin, acesulfame potassium, neotame and advantame.

Plant and fruit-based sweeteners are made from the leaves or fruits of certain plants and are at least 100 times sweeter than sugar, according to the FDA. They include extracts from the stevia plant and from monk fruit. Thaumatin, a less common low-calorie sweetener sold under the brand name Talin, is made from the West African katemfe fruit. The FDA generally recognises these sweeteners as safe, so manufacturers can add them to foods and drinks.

Sugar alcohols, which are neither sugars nor alcohols, are a type of carbohydrate that tastes sweet but has fewer calo- ries (and carbs) than sugar. They have names like sorbitol, xylitol, mannitol and erythritol and are naturally found in certain fruits and vegetables like pineapples, prunes and mushrooms. The kind used in packaged products are synthetically produced and permitted by the FDA for use as sugar substitutes.

What are the potential benefits and risks?

There is some evidence that if you regularly drink sugar- sweetened beverages like sodas and sweet teas, switching to diet versions may help you lose a little weight — as long as you don’t consume more calories from other sources, said Maya Vadiveloo, an associate professor of nutrition at the University of Rhode Island in the US.

But longer-term studies on sugar substitutes have found no weight loss benefits and even some harms. For this reason, the World Health Organization recommended in 2023 that people avoid using sugar substitutes for weight control or better health, citing research that linked them to greater risks of health concerns such as type 2 diabetes, cardio- vascular disease, obesity and earlier death.

The sugar alcohols erythritol and xylitol have also been associated with an increased risk of heart attack and stroke.

It’s hard to draw firm conclusions from studies on diet and health. This type of research is observational, meaning it can link the consumption of sugar substitutes with certain health effects, but it can’t really prove cause and effect, said Valisa E. Hedrick, an associate professor of nutrition at Virginia Tech in the US. It’s quite possible that those who drank diet soda are simply less healthy to begin with, she explained. Or perhaps other ingredients in the foods or drinks they prefer are responsible for causing harm.

The takeaway

Enough research has raised concerns about sugar substitutes to warrant a closer look, said Dr Eran Elinav, an immunologist and microbiome researcher at the Weizmann
Institute of Science in Israel who has studied them. In the meantime, “the jury is still out” on whether they’re harmful, he said, or if certain sugar substitutes are safer than others.

Too much sugar, on the other hand, is unquestionably harmful to health, Dr Elinav said, with research linking it to greater risks of type 2 diabetes, heart disease and obesity.

The American Heart Association recommends that women consume no more than 25 grams of sugar per day, and men no more than 36 grams per day. A 12-ounce can of Coca-Cola contains 39 grams of sugar.

Given those known harms, it’s better to choose artificially sweetened beverages like diet sodas over regular ones if you drink them every day, Dr Mozaffarian said. But, he added, the goal is to minimise your consumption of both over the long term.

NYTNS