Can Artificial Sweeteners Help With Weight Loss?

When saccharin, the first artificial sweetener, was discovered in 1879, it was considered a boon for people with diabetes. That’s because it could sweeten foods without triggering a spike in blood sugar, as an organization devoted to saccharin’s research and history notes. Since that time, a torrent of artificial sweeteners has flooded the market, with promises about not only diabetes management but also weight loss. The idea, of course, is that artificial sweeteners’ lack of calories and carbs allows people to enjoy sweet flavors without a high metabolic price tag. (Sounds like the ultimate example of “have your cake and eat it too,” no?)

As of 2023, the U.S. Food and Drug Administration (FDA) has approved six types of artificial sweeteners:

• Saccharin (Sweet’N Low, Sweet Twin, Necta Sweet)
• Aspartame (Nutrasweet, Sugar Twin, Equal)
• Acesulfame potassium, or Ace-K (Sweet One, Sunett)
• Sucralose (Splenda)
• Neotame (Newtame)
• Advantame

Each has its own unique advantages and drawbacks, and numerous studies have examined the safety and efficacy of each for weight loss. Still, faux sweeteners have been plagued by a variety of accusations, including that they cause cancer and make you pack on excess pounds rather than shed them. Adding to the confusing conversation, in May 2023, the World Health Organization (WHO) issued guidance that nonsugar sweeteners should not be used for weight loss.

Are you wondering whether reaching for a little pink or blue packet could really lead to weight loss? Here’s what science and the experts have to say.

Research on Artificial Sweeteners and Weight

Given the controversial interplay between artificial sweeteners and weight loss, it’s not surprising that studies on their relationship abound. Unfortunately, the conclusions aren’t clear-cut.

Some research suggests that alternative sweeteners might help you trim down. A meta-analysis of 20 studies published in Obesity Reviews in July 2020 concluded that nonnutritive sweeteners led to significant reductions in weight and BMI. A separate meta-analysis, from the August 2022 issue of Diabetes Care, meanwhile, analyzed data from 14 cohorts involving more than 416,000 subjects. In five of the cohorts, low- and no-calorie sweetened beverages were associated with lower weight, and in three cohorts, artificially sweetened drinks substituted for sugar-sweetened ones were linked with lower weight and incidence of obesity. But the researchers emphasized that these conclusions were of “low to very low certainty,” because of limitations in consistency and precision in the studies.

Other research has found the opposite to be true. A review published in January 2021 in Frontiers in Nutrition, for example, contended that the majority of clinical studies report no significant or beneficial effects of artificial sweeteners on body weight (though the authors noted that long-term studies on humans are scarce). Similarly, a systematic review published in the BMJ in 2019 found no evidence of any effect by nonsugar sweeteners on overweight or obese adults or children trying to lose weight. And in a real bombshell, an analysis of 37 studies published in the July 2017 Canadian Medical Association Journal revealed that people who regularly consumed artificial sweeteners actually had a higher body mass index (BMI) and risk of cardiometabolic disease than those who did not.

The WHO’s guidance advising against the use of nonsugar sweeteners for weight loss is based on a systematic review published in April 2022 conducted by the organization’s researchers, which determined that nonsugar sweeteners do not confer any lasting benefits for reducing body fat in adults or children. While this new guidance has sparked some heated discussion among health experts, some say it’s a helpful reminder not to pin weight loss hopes on a single ingredient. “In general, we know that you can’t simply replace one high-calorie food with one low-calorie food and expect weight loss,” says Caroline Thomason, RD, CDCES, who is based in northern Virginia. “In fact, it’s an accumulation of our habits and behaviors over time that contribute to our health.”

Are Artificial Sweeteners Healthy?

Regardless of whether artificial sweeteners lower the number on the scale, many people have concerns about their general safety. After all, they’re often synthetically produced and are a relatively new addition to our food supply. And, according to the WHO’s new research, long-term use of artificial sweeteners may increase the risk of worrisome health issues like type 2 diabetes and cardiovascular disease, as well as overall risk of death.

That said, there’s a long history of evidence that nonsugar sweeteners are safe for purposes like promoting weight loss and managing diabetes. “In my opinion, we have a lot of evidence to support the use of nonnutritive sweeteners,” says Thomason. She also points out that many people in research studies already have high risks for cardiovascular disease, diabetes, and other chronic diseases. “Thus, the research shows an association between the development of these chronic diseases and their risk but cannot prove causation,” she says.

While artificial sweeteners may fool your taste buds, your body knows the difference between real sugar and substitutes. “Our bodies process low- and no-calorie sweeteners differently than sugar. One result of sugar metabolism is calories. This is not the case with low- and no-calorie sweeteners,” explains Kris Sollid, RD, the senior director of nutrition communications with the International Food Information Council in Washington, DC. Some people may find this leaves them less satisfied.

“Anecdotally, some people do state that they have an increased craving response for more sugar-sweetened foods when they consume nonnutritive sweeteners,” says Thomason. “Your mileage may vary: It’s important to consider how you personally respond to nonnutritive sweeteners and decide if they are important for you to include in your diet or not.”

Again, artificial sweeteners have been extensively studied for safety, and generous upper limits are recommended by public health organizations. “The FDA has set an acceptable daily intake (ADI) for each sweetener,” says Justine Chan, RD, CDCES, the founder of Your Diabetes Dietitian in Toronto. “For example, the ADI for aspartame is 50 milligrams (mg) per kilogram (kg) of body weight each day. So if you weigh 68 kg, or 150 pounds (lb), you could safely have up to 3,400 mg of aspartame per day. Since there is roughly 200 mg of aspartame per can of diet soda, this would mean you’d need to drink up to 17 cans per day to reach your upper limit.”

Despite these safety indicators, with the newly issued WHO guidelines, it’s possible that federal guidance on the use of nonsugar sweeteners for weight loss may eventually change. “At the time of this being released, I don’t think it’s necessarily going to have an impact on U.S. guidelines; however, time will tell as we develop more data and gather more research in this area,” Thomason says.

There are groups who should be especially wary of artificial sweeteners. People with digestive disorders, for example, may need to be careful with certain options. “Individuals dealing with irritable bowel syndrome should avoid artificial sweeteners that contain sorbitol or erythritol, as they may aggravate the condition,” says Lisa Andrews of Sound Bites Nutrition in Cincinnati. She also recommends that people with the metabolic disorder phenylketonuria avoid aspartame.

People with diabetes should consider working with a registered dietitian or other healthcare professional before diving into the world of artificial sweeteners. Chan says that there is limited research on the safety of some newer options, like neotame and thaumatin, with diabetes. Still, she emphasizes that, in general, nonnutritive sweeteners can be an excellent (and even healthy) choice for people with the condition. “For example, a zero-calorie, artificially sweetened drink can substitute for your favorite sugar-sweetened drink because of their similar flavor profiles,” she notes. “People with diabetes often enjoy very little of the food they eat because of all the dietary restrictions, so it can be a nice alternative to have. In this way, artificial sweeteners can increase satisfaction and help you to stick to your meal plan over the long term.”

In general, it’s important to note that foods that use artificial sweeteners aren’t necessarily any healthier than those that are made with sugar. Many foods that incorporate these ingredients are highly processed or contain large amounts of saturated fat, sodium, and additives. Diligent label reading can help you determine a food’s overall nutritional picture.

Should You Use Artificial Sweeteners When Trying to Lose Weight?

With all the conflicting evidence swirling around artificial sweeteners and weight, it’s helpful to get expert insight into the matter. So, are these zero-calorie foods worth including in your diet if you’re looking to drop a pants size, according to dietitians and researchers?

In a nutshell, yes; it’s possible nonsugar sweeteners will help you lose weight, but that doesn’t mean it’s smart to rely on them exclusively. You can think of them as one solution for gradually cutting back on overall sugar and calorie intake, which leads to less body fat over time. “There are many approaches to losing and maintaining body weight, and the common food thread among them is cutting back on total calorie consumption,” says Sollid. “Because low- and no-calorie sweeteners provide zero or negligible calories, they can be helpful in reducing the number of calories, especially calories from added sugars in beverages, that we consume.”

If your weight loss journey involves a specific diet plan besides calorie-cutting — such as a Mediterranean diet, plant-based diet, or keto diet — you can choose to include artificial sweeteners in those, too. Because these products have few or zero calories and carbs, they won’t significantly interfere with counting macros or strategizing plant-forward meals. (Most artificial sweeteners are vegan.) Some diets, however, like Whole30, exclude the use of all sweeteners, including artificial ones. It’s up to you to determine your comfort level around including artificial sweeteners in your chosen diet plan.

Andrews agrees that alternative sweeteners can have a place in a weight loss diet. “While some nonnutritive sweeteners could impact glycemic control or pose a risk for weight gain, I still prefer clients use them over traditional calorie-containing sweeteners if diabetes management or weight loss are their goals.”

Just realize that reaching for a Diet Coke or a Sweet’N Low for your morning coffee isn’t a panacea for weight loss. “Artificial sweeteners are not a magic bullet, and consuming them does not guarantee weight loss or improved health,” says Sollid. “In addition to modifying what we eat and drink, successful weight loss and maintenance plans strive to simultaneously improve health and also encourage people to focus on things like regular exercise, sleep quality, and establishing and maintaining social support networks.”