Should You Be Worried About Aspartame? Here's What The Research Says

Science Alert ^ | May 07, 2025 | Staff

[Red Badger]

Sugar – sweet, satisfying, and everywhere. From fresh fruit and honey to processed table sugar and drinks, it sneaks into nearly everything we eat.

While delicious, sugar delivers what nutritionists call "empty calories" – energy without any essential nutrients. And with overconsumption linked to obesity, type 2 diabetes, heart disease and dental problems, it's no wonder health authorities are urging us to cut back.

The World Health Organization (WHO) recommends limiting added sugar to less than 10% of daily calorie intake, while the BMJ suggests even lower: no more than six teaspoons (25g) per day for women and nine teaspoons (38g) for men.

In response, many people are turning to non-nutritive sweeteners – sugar alternatives that deliver sweetness without the calories. These include popular options like aspartame, sucralose, stevia and monk fruit extract.

Found in many diet drinks, sugar-free snacks and low-calorie foods, these sweeteners are designed to help manage weight and blood sugar levels.

But not all that tastes sweet is sweet in effect. Let's zoom in on one of the most controversial sugar substitutes: aspartame.

Aspartame is an artificial sweetener that was discovered in 1965 and is 180–200 times sweeter than sugar. It was first regulated by the US Food and Drug Administration (FDA) in 1974 and approved for use in dry foods in 1981.

Today, it's estimated to be found in over 6,000 food and drink products and 600 pharmaceutical items.

Aspartame was initially embraced as a tool to help reduce obesity and support diabetics, offering a sweet fix without the sugar spike. But despite decades of use, its safety is still the subject of intense scientific and public debate.

Potential benefits Aspartame has a similar taste to sugar, albeit much more intense, but comes with almost no calories, making it attractive for those who're weight-conscious. With obesity rates soaring globally, even small calorie savings can matter.

Aspartame does not raise blood glucose levels, making it a preferred choice for those managing type 2 diabetes.

However, other research has found potential associations with metabolic syndrome and diabetes risk, suggesting that aspartame should be used as part of a controlled diet rather than a straight swap for sugar.

While assessments suggest that aspartame is safe within current intake guidelines, concerns persist.

Potential risks Some people may experience side-effects like headaches, dizziness, or mood changes. There's emerging evidence linking aspartame to neurodegeneration, strokes and even dementia.

Aspartame can increase levels of phenylalanine and aspartic acid in the brain, which is a serious concern for people with phenylketonuria (PKU), a rare inherited disorder where the body cannot break down phenylalanine.

This causes it to accumulate in the blood and brain, potentially leading to brain damage. People with PKU must avoid aspartame completely.

One study reported symptoms after consuming aspartame including irritability, migraines, anxiety and insomnia, especially with excessive consumption.

In 2023, the International Agency for Research on Cancer (IARC) classified aspartame) as "possibly carcinogenic", though it remains approved for consumption within existing safety limits. Some studies suggest a link to cancer, but conclusions remain mixed.

It's also advised that pregnant women avoid aspartame, as research suggests it may affect the placenta's structure and function.

Artificial sweeteners, despite being calorie-free, may trick the brain into craving more sweetness. This could lead to increased appetite and weight gain rather than weight loss. In fact, several studies have found a positive correlation between artificial sweetener use and obesity.

Gut health matters Emerging evidence suggests that aspartame and other sweeteners may disrupt the gut microbiome, the community of bacteria that play a key role in digestion, immunity and even mood.

This disruption can negatively affect digestive health and immune function, potentially increasing the risk of infections and other health issues.

Aspartame may offer a tempting sugar-free fix, but it's not without its risks. The World Health Organization advises against using non-sugar sweeteners for weight control and research continues to reveal complex links between aspartame and chronic diseases, from neurological issues to gut health concerns.

Hazel Flight, Programme Lead Nutrition and Health, Edge Hill University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

[metmom]

Likely. That’s the case with MANY things.

Look at who is funding studies on sketchy food additives.

[dennisw]

I hear you can buy Coke with sugar to sweeten it at Oriental supermarkets. They might be bringing in Mexican coca cola

[Some Fat Guy in L.A.]

We’re all different and react differently to many things. I have been using aspartame sweetened soft drinks since they first came out - my mom was diabetic and we didn’t have sugary drinks in the house, so I got used to sugar free. I always hated saccharine, though - tastes bitter to me. Aspartame was such a relief when it came out - tastes fine to me and no apparent problems from it. Splenda also tastes good to me, and I can use it in cooking where aspartame doesn’t work. I’ve tried stevia but it tastes metallic to me. Haven’t tried Swerve yet - my doc says it is the best one health wise, but it’s really expensive.

[fwdude]

Fruit was once considered dessert after meals.

I was on a low carb diet which recommended as a dessert a quartered pear with a scoop of ricotta cheese. It was one of the best desserts I can ever remember.