Diet sodas and sugar-free alternatives promise to slim your waistline and improve your health. But are artificial sweeteners any better than the sugar they’re replacing?
Studies proclaiming the harms of non-nutritive sweeteners like aspartame and stevia have flooded headlines in recent years, linking the compounds to illnesses from type 2 diabetes to cardiovascular disease.
In the other corner, scientists have performed decades of research on sugar and the myriad of health complications overindulgence can lead to, from obesity and metabolic disease .
We’ve searched and searched for a healthy way to consume lots of sugar. Scientists say that’s not going to work.
We’ve searched and searched for a healthy way to consume lots of sugar. Scientists say that’s not going to work.
“I think in general, people should be trying to avoid products that have either added sugar or non-nutritive sweeteners,” said Rachel Murphy, an associate professor researching nutrition and metabolism at the University of British Columbia.
But if you had to choose, which should you go with?
Are artificial sweeteners better for you than sugar?
Sabrina Ayoub-Charette has spent years researching this very question for her Ph.D thesis at the University of Toronto. Her team’s yet-to-be published results point to a definite conclusion: Yes, artificial sweeteners are better (or at least less bad for you) than regular sugar.
Swapping from sugary to sugar-free may lead to lower body weight and a decreased risk of obesity, chronic heart disease, chronic vascular disease and all-cause mortality, concluded her lab’s upcoming review, the results of which were shared at a Canadian Nutrition Society conference earlier this month.
The findings build on , which suggested there was no metabolic or cardiovascular harm in switching from sugary beverages to their diet counterparts. In some cases, drinking diet had benefits similar to swapping sugary drinks for water.
“Our results were able to show that, compared to the sugary alternative, using diet beverages are actually very beneficial,” she said. “If you already are drinking sugar-sweetened beverages, diet beverages can be a helpful replacement.
“But it’s just a stepping stool to help people get off the sugary drinks. Water is still the gold standard.”
The sugar alternative is often found in oral health products and keto-diet foods.
The sugar alternative is often found in oral health products and keto-diet foods.
Murphy disagrees.
“Personally, I would choose the one with sugar in it,” she told the Star. Murphy reasoned that, compared to sugar, there’s still much we don’t know about the long-term harms of artificial sweeteners — especially their implications for diseases like cancer, which can take years to develop.
It depends on your personal situation, she said. If you’re living with diabetes, for example, it may be better to stick with diet, as it can help you moderate your blood sugar levels.
But given the bevy of recent research linking artificial sweeteners with poor health outcomes, Murphy believes sugar-free alternatives deserve more wariness.
Are artificial sweeteners bad for you?
In 2023, the World Health Organization issued a controversial guideline recommending against the use of artificial sweeteners for weight management.
concluded that sweeteners like aspartame and stevia had no benefit for long-term weight loss — in fact, long-term consumption of these sweeteners was linked to a greater risk of type 2 diabetes, cardiovascular disease and death in adults.
Further studies have linked other non-sugar sweeteners like erythritol to heart attacks, strokes and other cardiovascular events. One 2024 review suggested diet beverages were , chronic heart disease, hypertension, type 2 diabetes, metabolic syndrome and certain cancers including leukemia.
It seems like an open-and-shut case, right? Not necessarily, said Dana Olstad, a registered dietitian and associate professor of public health nutrition at the University of Calgary.
So how much is too much? While it doesn’t mean it’s time to quit Diet Coke, it’s a good idea to watch your intake, experts tell the Star.
So how much is too much? While it doesn’t mean it’s time to quit Diet Coke, it’s a good idea to watch your intake, experts tell the Star.
Most of these papers are based on observational studies and “very poor quality evidence,” Olstad noted. For example, the studies might ask participants how often they ate sugar-free alternatives in a week — but had no way of assessing the amount or type of sweeteners actually present in the foods they’re eating.
Nor do the studies account for other food additives that might be contributing to the supposed health harms, she said. “Then they lump all those sweeteners together when they are entirely different compounds.”
“Just because something is artificial does not mean it’s unsafe, and just because something is natural does not means it’s safe,” Olstad said. “Arsenic is natural, but it’s not very safe.”
A urged the WHO to reconsider their guidelines, citing concerns similar to Olstad’s. It argued that, when compared to the sugary originals they’re meant to replace, sugar-free alternatives have been shown to provide numerous health benefits.
The same paper added that people already living with metabolic and cardiovascular illnesses are more likely to turn to sugar-free alternatives — meaning sweetener consumption may be a response to disease risk, not a cause of the harm.
Is sugar always bad for you?
The federal government acknowledges that food marketing campaigns have a significant factor on what we eat. Should Canada restrict food ads to
The federal government acknowledges that food marketing campaigns have a significant factor on what we eat. Should Canada restrict food ads to
In Olstad’s opinion, diet sodas and artificial sweeteners are “100 per cent” healthier than the sugary original. “The major benefit is that you’re reducing your calorie intake, so you are less likely to gain weight,” she said.
That doesn’t mean all sugar is bad for you — it’s a necessary energy source for our bodies. But there’s a big difference between the sugar found in fruit and those added into ultra-processed foods.
A chocolate bar containing no fibre and few nutrients has nothing to slow the absorption of sugar into our bodies, leading to a spike in blood sugar. The additives present within can lead to additional health harms, Murphy noted.
But an apple, packed with fibre and other goodies, will release its sugar slowly into our blood, resulting in a healthier outcome, Olstad explained.
“We don’t want to overdo it on sugar, but it’s not the root of all evil.”
To join the conversation set a first and last name in your user profile.
Sign in or register for free to join the Conversation