Experts break down a whole list of artificial sweeteners and weigh in on which ones are best

By Rebecca Brown
Updated August 27, 2019
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It's no secret—large quantities of sugar aren't great for your body, from causing inflammation to increasing the chance of developing obesity and coronary heart disease. For these reasons, the American Heart Association (AHA) recommends that the average American limit their intake of added sugar to just 6 teaspoons for women and 9 teaspoons for men.

But are sugar substitutes any healthier? Is there a single best artificial sweetener? We turned to medical and nutrition pros for a common artificial sweeteners list and an honest, scientific breakdown of artificial sweeteners vs. sugar.

The Not-So-Sweet Side of Artificial Sweeteners vs. Sugar

It seems like a miraculous wish come true in a tiny, colorful packet. You can still enjoy your coffee nice and sweet without any extra calories. But over the years, valid arguments have formed stating artificial sweeteners can actually lead to weight gain.

"Artificial sweeteners stimulate our body to produce the weight gain hormone insulin, which causes the body to store calories as fat," Morrison says. And even though in previous AHA statements have claimed that non-nutritive sweeteners did have the potential to help people reach and maintain their goal weights, they also stated that the evidence was limited and therefore inconclusive. (Related: Why a Low-Sugar or No-Sugar Diet Could Be a Really Bad Idea)

Plus, many of the sugar substitutes found in diet foods and beverages are jam-packed with chemicals, which can put a strain on your immune system. "When we ingest these chemicals, our bodies need to work extra hard to metabolize them, leaving less resources to detoxify our bodies from the many chemicals we get exposed to in the environment," says Jeffrey Morrison, M.D., a physician and nutrition adviser for Equinox fitness clubs.

But when it comes to the sweet stuff, which are the worst offenders? What's the best artificial sweetener? As you weigh the pros and cons of artificial sweeteners vs. sugar, read on for your guide to the best and worst on this artificial sweeteners list.


Sold under names like NutraSweet® and Equal®, aspartame is one of the more controversial and studied sweeteners on the market. In fact, "by 1994, 75 percent of all non-drug complaints to the FDA were in response to aspartame," says Cynthia Pasquella-Garcia, a clinical nutritionist and holistic practitioner. Those gripes ranged from vomiting and headaches to abdominal pain and even cancer.

Aspartame vs. Sugar: Aspartame has zero calories and is often used for baking. It contains a broth of unfamiliar ingredients, such as phenylalanine, aspartic acid, and methanol.

"The methanol from aspartame breaks down in the body to become formaldehyde, which is then converted into formic acid," says Pasquella-Garcia. "This can lead to metabolic acidosis, a condition where there is too much acid in the body and leads to disease." Even though aspartame's link to health problems has been highly studied, there's very little evidence to keep it off shelves. The Food and Drug Administration (FDA) has set the accepted daily intake (ADI) at 50 mg/kg of body weight, which equals about 20 cans of aspartame-sweetened beverages for a 140-pound woman.


Known as Splenda (and also marketed as Sukrana, SucraPlus, Candys, and Nevella), sucralose was initially developed in the 1970s by scientists who were trying to create an insecticide. Splenda is often touted as the most natural sweetener because it comes from sugar, but during the production process, some of its molecules are replaced with chlorine atoms. (Related: How to Cut Back on Sugar in 30 Days—Without Going Crazy)

Sucralose vs. Sugar: On the upside, sucralose has no effect on immediate or long-term blood glucose levels. "Splenda passes through the body with minimal absorption, and although it's 600 times sweeter than sugar, it has no effect on blood sugar," says Keri Glassman, R.D., a registered dietitian and author of the Slim Calm Sexy Diet.

Even so, skeptics have been concerned that the chlorine in sucralose could still be absorbed by the body in small amounts. In 1998, the FDA completed over 100 clinical studies and found that the sweetener had no carcinogenic effects or risk associated. Ten years later though, Duke University completed a 12-week study—funded by the sugar industry—administering Splenda to rats and found that it suppressed good bacteria and reduced fecal microflora in the intestines. "The findings (while they were in animals) are significant because Splenda reduced the probiotics, which play a key role in maintaining a healthy digestive system," says Ashley Koff, R.D., a registered dietitian and founder of The Better Nutrition Program. The ADI is currently set at 5 mg/kg of body weight, meaning a 140-pound female could easily have 30 packets of Splenda per day. (Also worth reading: How the Sugar Industry Convinced Us All to Hate Fat)


Most commonly known as Sweet 'N Low, saccharin is one of the oldest low-calorie sugar substitutes available. It's an FDA-approved option that's been widely tested, yielding a slew of conflicting reports.

Saccharin vs. Sugar: Saccharin was first categorized as a carcinogen in the '70s, when research linked it to bladder cancer in lab rats. However, the ban was lifted in the late 2000s when later studies proved that rats have a different makeup to their urine than humans do. Even so, pregnant women are typically advised to use saccharin sparingly.

With respect to weight-loss benefits, saccharin has zero calories and doesn't raise blood glucose levels, but dietitians believe the sweetener can be linked to weight gain. "Usually when one eats a sweet food, the body expects calories to accompany that food, but when the body does not get those calories, its looks for them elsewhere," Glassman says. "So for every calorie that you think you save by choosing an artificial sweetener, you are likely to gain by eating more calories in the end." The ADI for saccharin is 5 mg/kg of body which is the equivalent of a 140-pound woman consuming 9 to 12 packets of the sweetener. (Related: What You Need to Know About the Latest Artificial Sweeteners)

Agave Nectar

Agave isn't exactly an artificial sweetener. It's used as an alternative to sugar, honey, and even syrup and is produced from the agave plant. While the OG versions of agave syrup were produced naturally, much of what's available in supermarkets now has been overprocessed or chemically refined. It's 1.5 times sweeter than sugar, so you can use less. Don't be surprised to find it in health food bars, ketchup, and some desserts.

Agave vs. Sugar: "Agave nectar has a low glycemic index, which means this form of sugar is absorbed more slowly by the body so it causes a relatively lower spike in blood sugar and less of a sugar rush than other forms of sugar," says Glassman. However, agave is starch-based, so it's not that different from high-fructose corn syrup, which can have adverse health effects and increase triglyceride levels. Different agave manufacturers use varying amounts of refined fructose, one of the primary sugar components of agave, which is similar to high-fructose corn syrup and can sometimes be more concentrated.

Even though the agave plant contains inulin—a healthful, insoluble, sweet fiber—the agave nectar doesn't have very much inulin left over after processing. "One of the effects of agave nectar is that is can cause a condition of fatty liver, where sugar molecules accumulate in the liver, causing swelling and liver damage," says Morrison.

"Agave can actually have amazing health benefits, but many brands of agave on the market are chemically refined," echoes Pasquella-Garcia. She recommends raw, organic, and unheated agave because it is said to have anti-inflammatory, antimicrobial, and immune-boosting abilities if consumed in moderation (and within the AHA guidelines of less than 6 teaspoons per day total of added sugar).


Fans of this South American herb prefer it to regular table sugar because of the no-calorie appeal. It's available in both powdered and liquid form and nutritionists note that it's chemical- and toxin-free. (More myth-busting: No, a banana doesn’t have more sugar than a doughnut.)

Stevia vs. Sugar: In 2008, the FDA declared stevia to be "generally regarded as safe," which means it can be used as a sugar substitute. Studies have shown that stevia can lower insulin levels, making it a favored option for diabetics, though some are still worried about the brands of sweeteners that use stevia. "While stevia is regarded as safe, we don't know about all of the blends sold in supermarkets," says Koff. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has assigned it an ADI of 4 mg/kg (or 12 mg/kg body weight for steviol glycoside) which means that a 150-pound person could consume around 30 packets.


With the closest comparable taste to sugar, this well-known sugar alcohol derived from birch bark is found in many fruits and vegetables and is produced in the body. Xylitol contains roughly 2.4 calories per gram, has 100 percent of the sweetness of table sugar, and when added to foods can help them stay moist and textured. (Here's more about sugar alcohols and whether they're healthy or not.)

Xylitol vs. Sugar: Advocates of this FDA-regulated option favor the non-caloric sweetener because it's safe for diabetics and research has shown that it promotes dental wellness. "Like stevia, xylitol is naturally derived, but it is not absorbed from the digestive tract, so if too much is consumed, it can cause loose bowel movements," Morrison says. Most products containing xylitol post warnings about the laxative-like effects. The ADI for xylitol is not specified, which means there are no limits that may make it hazardous to your health. (Related: How One Woman Finally Curbed Her Fierce Sugar Cravings)