Are Artificial Sweeteners Bad for You?

Sweeteners go by many names

A number of calorie-free sugar substitutes are on the market — some are referred to as artificial, some natural. And chances are, you’ve consumed them without realizing it.

“They’re increasingly used because consumers are concerned about sugar. And so, companies are responding to that not with the most obvious thing — making foods less sweet — but they’re using these instead,” says Dariush Mozaffarian, M.D., a cardiologist and professor of nutrition at the Friedman School of Nutrition Science and Policy at Tufts University.

Six artificial sweeteners have been approved by the FDA:

• Saccharin (Sweet’N Low). You can find it in sugar-free gums and candies, even toothpaste.
• Aspartame (Equal). You can find it in popular zero-calorie soft drinks.
• Acesulfame potassium (Sunett, Sweet One). You can find it in frozen desserts, candies, beverages and baked goods.
• Sucralose (Splenda). You can find this in baked goods, even salad dressings.
• Neotame (Newtame). You can find this in baked goods.
• Advantame. This sweetener, with no brand name, is also used in baked goods.

There are others, too, that the FDA considers “generally recognized as safe” and that don’t have to go through the same safety review as those on the list above. They include:

• Luo han guo (Monk Fruit in the Raw)
• Purified stevia leaf extracts (Truvia)
• Sugar alcohols, like erythritol. Sugar alcohols are neither sugar nor alcohol, but carbohydrates that have chemical characteristics of both, according to the FDA. And while they are found naturally in some fruits and vegetables, the kind you find in packaged products are commercially produced. Other than erythritol, common sugar alcohols include maltitol, sorbitol and xylitol.

These nonnutritive sweeteners pop up in a range of products, from yogurts to oatmeal to ice cream. Sometimes they’re mixed with other sweeteners.

Wondering if there’s a difference between artificial sweeteners and the so-called natural ones? Mozaffarian says “that’s a little bit of an artificial distinction,” since many of the natural options are used at levels much higher than a person would consume if they, say, ate a slice of watermelon or a handful of grapes.

“Something being natural doesn’t necessarily mean it’s safe at [high] doses,” Mozaffarian says. “At the same time, something artificial doesn’t necessarily mean that it’s harmful.”

Should you make the sweetener switch?

There’s no doubt that cutting down on the amount of sugar you consume through foods and drinks can be a boon for your health. And most Americans have some work to do: The average U.S. adult consumes about 77 grams of sugar per day — more than three times the recommended amount for women, according to the American Heart Association.

But should you swap the real stuff for a zero-calorie alternative?

Not so fast. Mozaffarian says one way to think of nonnutritive sweeteners is more like a bridge and less like a destination. “If you’re going to have a 20-ounce soda, it’s probably better to have a diet [soda]. But, you know, better to have neither,” he says. (The WHO said in May that replacing sugar with zero-sugar sweeteners does not help with weight loss and management over the long term.)

If you’re trying to limit your intake of nonnutritive sweeteners, know that doing so can be difficult. They creep into a lot of packaged products, and many people are not familiar with all the varieties on the market. (You may have heard of aspartame — but acesulfame potassium or adventame?) What’s more, manufacturers aren’t required to include sugar alcohols, like erythritol, in the ingredient list on a food’s label.

“Sometimes you’ll see it just as natural sweeteners or natural flavors,” the Cleveland Clinic’s Hazen says.

A good rule of thumb: “If it tastes sweet and it says low-sugar, it’s likely got one of these in it,” Mozaffarian says. Packages advertised as low-calorie can be another giveaway, adds Martha Field, an assistant professor in the Division of Nutritional Sciences at Cornell University.

Many experts and organizations stress that more research on sweetener safety is needed, including long-term studies. While we wait, Field says, “it never hurts to be more aware of what you’re eating.” And if you’re concerned about the effects of sugar or sugar substitutes on your health, talk to your doctor or a dietitian, who can “help you sort through some of your personal risks,” Field adds.

Another tip to help you avoid added sugar and sugar substitutes: Stick to a diet rich in whole foods as much as possible. “I always recommend to my patients to shop the produce aisle,” Hazen says.

Editor's note: This story, originally published April 10, 2023, has been updated to reflect new information.