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.
This article is republished from The Conversation under a Creative Commons license. Read the original article here.
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May 9, 2025
