Do artificial sweeteners cause cancer?

Key takeaways:

• Artificial sweeteners are made from chemicals and are far sweeter than normal table sugar, sometimes with as much as 200 to 700 times the sweetness. Aspartame is the most commonly researched artificial sweetener.
• The International Agency for Research on Cancer (IARC) classified aspartame as “possibly carcinogenic,” but the U.S. Food and Drug Administration (FDA) disagrees with the conclusion and does not have safety concerns when aspartame is used under the approved conditions.
• The FDA sets the maximum daily intake for aspartame at around 23 mg per pound of body weight (50 mg/kg), but all sugar and sweeteners should be consumed in moderation.

From your morning coffee to your afternoon diet soda, artificial sweeteners may be more common in your daily routine than you realize. These sugar substitutes add sweetness with few or no calories, and you’ll find them in familiar brands like Equal, Splenda, Truvia (made from Stevia) and Sweet’N Low. Aspartame is the most commonly researched artificial sweetener—so how does it affect your health?

Is there a link between aspartame and cancer risk?

The International Agency for Research on Cancer (IARC), the cancer research agency of the World Health Organization (WHO), in 2023 released its assessment of the health impacts of artificial sweeteners. The assessment focused on aspartame, one type of sugar substitute.

The report classified aspartame as “possibly carcinogenic” to humans—meaning it may cause cancer—based on a limited amount of evidence linking it to cancer in humans, specifically to a type of liver cancer.

But it’s not so simple: The U.S. Food and Drug Administration (FDA) released a statement in response to the IARC report stating they disagree with the conclusion that artificial sweeteners are possibly carcinogenic.

The FDA cited that aspartame is one of the most studied food additives, and FDA scientists do not have safety concerns when aspartame is used under the approved conditions—especially considering that after the IARC evaluated the data, they made no changes to their recommended daily intake of aspartame.

What products contain aspartame?

Since aspartame is a lower calorie option compared to regular sugar, it is often found in diet products, such as diet sodas, sugar-free chewing gum, diet drink mixes, gelatin and tabletop sweeteners. Popular brand examples include Diet Coke, Trident gum, Crystal Light and Jell-O.

If you’re curious about whether or not a product does contain aspartame, check the ingredient listing on the nutrition label. Other sugar substitutes you may find in ingredient listings are sucralose Und saccharin, but those two products were not listed in the IARC health report and both the WHO and the FDA agree that they are safe for general consumption.

What’s the difference between natural sugar, added sugar and artificial sweeteners?

Sugar is a simple carbohydrate which gives your body calories and a quick burst of energy. Your body needs sugar, but it’s important to know what kind of sugar you’re consuming.

Natural sugar is found in foods like fruit, vegetables and whole milk and contains nutrients, like fiber and vitamins. When eaten in these whole forms and compared to added sugar, natural sugar has little impact on weight gain or any chronic illnesses. Natural sugar is also digested at a slower rate, which keeps your energy levels steady rather than spiking and dropping.

Added sugar is not inherently present in food. As the name suggests, it is added to foods during cooking or processing—think sodas, candy, baked goods, flavored yogurts and sauces. Your body digests added sugars quickly, which can cause blood sugar spikes and crashes. High intake is strongly linked to obesity, type 2 diabetes, heart disease and some cancers.

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Artificial sweeteners are not sugar, nor do they contain sugar. They are made from chemicals, which make these substitutes far sweeter than normal table sugar, sometimes with as much as 200 to 700 times the sweetness. They do not affect your blood sugar levels, and since they have no calories, they do not contribute to weight gain.

Are there other health impacts of artificial sweeteners?

Though artificial sweeteners are not linked to cancer, they should still be consumed with caution.

A specific type of artificial sweetener called sugar alcohol, which does contain a few calories, can impact your gut health. These products are known to cause gas, bloating, diarrhea and other gastrointestinal issues.

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Because artificial sweeteners are far sweeter than natural sugar, some experts theorize that artificial sweeteners could impact sugar cravings. Increased sugar cravings can lead to higher consumption of sweets in general, including unhealthy products with added sugar. While there has been einige Recherchen on this topic, results were inconclusive and more studies need to be done to provide a clear picture.

The bottom line: Artificial sweeteners have no nutritional value. So, while they may not have the most negative impact on your health, they also don’t provide any added benefits.

Should I cut out sweeteners altogether?

As with many things in life, sugar and sweeteners should be consumed in moderation. But there are vastly different portion recommendations for artificial sweeteners, added sugar and natural sugar.

Der FDA sets the maximum daily intake for aspartame at around 23 mg per pound of body weight (50 mg/kg). European and international regulators recommend no more than 18 mg per pound of body weight per day (40 mg/kg).

Added sugar, however, has a far lower daily limit. The American Heart Association says men should consume no more than 9 teaspoons of added sugar per day, and women should consume no more than 6 teaspoons.

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Let’s put these numbers into perspective:

• A person weighing 154 lb. (70 kg) would have to consume at least 9–14 cans of diet soda per day (depending on the level of aspartame in each can) to exceed the artificial sweetener limit of 40 mg/kg/day.
• A person of any weight would reach or exceed the added sugar limit with a single 12-ounce can of regular soda.

If you have a sweet tooth, aim for natural sources of sweetness—fruit, whole foods and minimally processed options. Use added sugar sparingly and rely on artificial sweeteners when they help you cut back, not as a replacement for all sweetness.

A balanced diet with fewer ultra-processed foods and more whole foods is the sweetest strategy for long-term health.