Growing evidence suggests artificial sweeteners may be linked to heart disease and other health risks, but scientists say the study’s findings are inconclusive, and some leading researchers have called for better designed clinical trials to study the long-term health effects of sugar substitutes.
That’s why researchers are actively working in separate trials to get a clearer understanding of how artificial sweeteners affect blood sugar levels, gut microbiome health, and the cardiovascular system. Some studies are beginning to compare alternative sweeteners with each other, while others are looking to see how artificial sweeteners affect the body compared to sugar.
As things stand, it’s difficult for consumers to determine which sugar alternatives pose the fewest health risks. Most of the studies are observational and don’t prove causation. In some cases, researchers have looked at people who consumed sweeteners other than sugar and analyzed the incidence of certain health risks, such as heart attacks or diabetes, noting associations between the two.
All of the widely consumed substitutes, including saccharin, aspartame, sucralose, stevia, xylitol, and erythritol, are Food and Drug Administration. It’s found in countless products, including sports drinks, energy bars, yogurt, cereals, beverages, candy, baked goods, and syrups.
Even with FDA approval, “they’re all potentially concerning and understudied,” said Dr. Dariush Mozaffarian, a cardiologist and professor of nutrition science and policy at Tufts University.
In a recent study, Cleveland Clinic cardiologist Dr. Stanley Hazen found that high concentrations of the sugar alcohol sweeteners xylitol and erythritol may make blood platelets stickier and more likely to clot, increasing the risk of heart attack and stroke. This is similar to what happens with high cholesterol, Dr. Hazen says. If the clot grows large, it can block blood flow through vital veins and arteries.
Some experts say that rather than trying to identify which non-sugar sweeteners are the safest, better research is needed to determine whether there are benefits to replacing sugar in the first place.
After publishing a study that found an association between erythritol and an increased risk of heart attack and stroke, Hazen and his colleagues conducted the first head-to-head study to compare the effects of erythritol intake with sugar intake on platelets, which control blood clotting. Results of this study are pending publication.
Meanwhile, Vasanti Malik, an assistant professor of nutritional sciences at the University of Toronto, is conducting a head-to-head study of more than 500 people comparing the health effects of drinking sugary drinks, non-caloric sweeteners, and water. She and her colleagues plan to measure obesity and heart health over the long term.
At Virginia Tech, registered dietitian Varisa Hedrick is working with the National Institutes of Health on another study comparing the effects of four artificial sweeteners and sugar on blood sugar and gut microbiome health. The study, in people with prediabetes, is a controlled-diet trial, in which participants eat only the NIH-provided diet and nothing more.
This is important, Hedrick says, because one of the growing concerns about non-sugar sweeteners is that these products trick the brain into increasing sugar cravings, which can lead people to eat more sugar throughout the day, causing blood sugar to spike.
Controlled studies would allow researchers to answer whether the sweeteners themselves directly raise blood sugar levels — meaning the sugar people later ingest raises their blood sugar levels.
Limitations of sweetener research
Malik said a research bias called reverse causation can make it difficult to draw definitive conclusions from previous studies.
Malik says that many people change their diet when they develop diabetes or start gaining weight, and they are generally more likely to switch to non-sugar sweeteners — this is where reverse causation comes into play.
“There is a spurious association between consumption of non-sugar sweeteners and risk of diabetes,” she says, meaning the data ultimately suggests that these sweeteners are causing pre-existing health problems.
Many studies also rely on having subjects report whether they consumed non-sugar substitutes, but this can be unreliable: names like xylitol can get lost in long ingredient lists.
Meanwhile, other studies, like Hazen’s erythritol and xylitol studies, may focus directly on what happens in the body after ingesting one of these sweeteners, but they tend to enroll small numbers of subjects and follow them for only a short period of time.
“A lot of these studies are very difficult to interpret,” says Dr. Michelle Pearlman, a gastroenterologist and CEO and co-founder of Prime Institute in Miami, “and the problem is, we don’t have head-to-head studies of people eating candy bars versus eating xylitol, so we can’t make blanket statements recommending one over the other.”
Hedrick and Malik hope to share the results of their research in the coming years.
“We need experimental science alongside more rigorous observational studies,” Malik said. “Experiments are ongoing, and I think we’ll have a clearer answer on this within the next five years. We’re not there yet.”
The Calorie Control Council, a trade group that represents more than 20 sweetener manufacturers, said in a statement that studies linking alternative sweeteners to health risks are based on flawed research and that alternative sweeteners are safe.
“It is irresponsible to promote faulty research to people who rely on alternative sweeteners to reduce their total sugar intake, or to the millions of people who use them as a way to manage health conditions like obesity and diabetes,” Carla Sanders, president of the industry group, said in a statement.
Why it’s important to know
Most low-calorie and sugar-free foods contain at least one sugar substitute, and many contain more than one. These products are becoming increasingly popular, especially in the United States. By 2033, Market research It suggests that sugar substitutes could be worth more than $28.57 billion.
“They’re everywhere,” Mozaffarian said, “and they’re proliferating because people have become so obsessed with avoiding sugar.”
Mozaffarian said these sweeteners: 2016 U.S. Nutrition Labeling Requirements.
The change required manufacturers to list added sugars on a separate line below total sugars, which was intended to make it easier for consumers to distinguish between foods that contain natural sugars, such as fruit or plain Greek yogurt, and foods that have sugar added to them.
“Right now, the food industry has a huge incentive to reduce the amount of ‘added sugars,'” he says, “so everything has these compounds in it, but we don’t know enough about them yet.”
Some products are labeled as “artificial sweeteners” or “natural sweeteners” depending on whether they are naturally derived or chemically synthesized.
Dr. Maria Carolina Delgado Leliever, a cardiologist at the University of Miami, said even natural sweeteners undergo harsh chemical processing.
For example, stevia is made from an extract of the stevia plant, Monk fruit sweetener is made from chemicals found in a gourd-like fruit grown in China, and sucralose is a chemically altered form of sugar that is about 600 times sweeter. According to the FDA.
Aspartame and saccharin are artificial combinations of amino acids and chemicals.
Hazen of the Cleveland Clinic said that even small amounts of many of these sweeteners are very strong, so they are sometimes mixed with xylitol or erythritol to bulk them up in bags.
Hedrick said that in light of this labeling confusion, researchers are beginning to use the term “non-sugar sweeteners” more and more.
Sugar, of course, is one of the country’s most pressing public health problems: Excess sugar, especially in sodas and juices, is fueling the ongoing obesity epidemic and contributing to heart disease, liver disease, cancer and diabetes.
But there’s a big difference between processed, concentrated sugars like high-fructose corn syrup and the natural sugars found in fruit, says Pearlman, a Miami gastroenterologist: Processed sugars are highly addictive.
“Anything that contains high fructose corn syrup stimulates the same reward centers in the brain as cocaine and heroin,” she says. “The natural sugars found in fruit act differently in the body.”
Experts agree that sugar’s bad reputation has more to do with the amount people consume than any negative qualities in sugar itself.
“Added sugar is nuanced,” Mozaffarian said, “and by trying to translate that very real nuance into a simple message, the food industry ends up misleading consumers into thinking food is bad.”
He says small amounts of added sugar to healthy foods, such as lightly sweetened whole-grain cereals, are usually fine.
“The harms of these various non-sugar sweeteners have been underemphasized and the harms of small amounts of added sugar have been overemphasized,” he argued.
Sugar alternatives for kids?
The U.S. government’s Dietary Guidelines for Americans recommends that people over the age of 2 consume less than 10% of their daily calories from added sugars, or about 12 teaspoons. In fact, as of 2018, Americans, including children, were consuming On average, that’s about 17 teaspoons of added sugar per day.
Recently, the U.S. Department of Agriculture New rules limiting added sugar in public school lunchesMichael Golan, a professor of pediatrics at the Keck School of Medicine of the University of Southern California, said he was concerned that schools would replace sugary foods with artificially sweetened options to comply with the new rules.
“There’s a general perception that these sweeteners are a safe alternative, but if they’re applied broadly to children, I think unfortunately it’s very dangerous,” he said.
Mozaffarian said that given current levels of added sugar, most yogurts would be banned from school lunches once the new rules come into effect.
“Being just above the new limit, it’s likely that these yogurts are made with a range of sweeteners whose health effects are unknown,” Mozaffarian said.
But Pearlman said it’s clear the program isn’t helping improve the overall health of the nation.
“Chronic disease and diabetes are on the rise like never before,” she says, “and it shows that, despite the diet industry being worth billions of dollars, we’re clearly missing the point.”
Confusion from limited research, combined with a lack of clarity on food labels, puts consumers in a difficult position when it comes to choosing the healthiest options, experts concluded.
Everyone agreed on the best solution.
- Eat as many unprocessed foods as possible.
- The less processed a food is, the less likely it is to contain large amounts of added sugars or non-sugar sweeteners.
“If I had to choose between a store-bought cookie with lots of sweeteners, a store-bought cookie with monk fruit, or a homemade cookie with sugar, I’d choose the homemade cookie,” Golan says. “The cookie is still delicious, but it could use a little less sugar.”
