Aspartame and cancer

There has been a lot of talk in the research and cancer world about artificial sweeteners (like aspartame) over the last few weeks. Let’s cut through the noise and get to the important part; will eating or drinking aspartame give me cancer?

If you’re looking for a short and simple answer, then it’s “No – eating or drinking foods with aspartame added to them is very unlikely to give you cancer.”

If you’re interested in the detail, then read on!

What is aspartame?

Let’s start with the basics; what is aspartame?

Aspartame is one of the many different types of artificial sweeteners that have been created to replace sugar in food. Other examples include saccharin, sorbitol and xylitol. They are chemical substances that taste even sweeter than traditional sugar. For example, aspartame is about 200 times sweeter than table sugar.

The theory is that you can use a much smaller amount of artificial sweetener than sugar and food will still taste just as sweet. But as you have used less of it, the food will have fewer calories in it making it easier to keep a healthy weight. More on this later.

Aspartame is used in lots of different products, such as fizzy diet drinks, cereal, low-sugar yoghurts, frozen desserts, and chewing gum. Researchers discovered it by accident in 1965 when they were trying to create anti-ulcer drugs. It is made up of two amino acids (the building blocks of all life).

Who are IARC and what is their rating system?

The International Agency for Research on Cancer (usually shortened to IARC) are the cancer arm of the World Health Organization (WHO). The organisation is based in France and conducts research on the causes of cancer, as well as publishing data on how many cancer cases there are around the world.

For its research on what causes cancer, IARC created a ranking system to classify how strong they think the evidence is that something increases the risk of cancer. There are four levels:

Group 1 – Carcinogenic to humans. Things in this group include smoking, alcohol and processed meat.
Group 2A – Probably carcinogenic to humans. This is where red meat is
Group 2B – Possibly carcinogenic to humans. This is the group aspartame has been placed in, along with things already in the group like aloe vera and bracken fern (types of plants)
Group 3 – Not classifiable as to its carcinogenicity to humans. This is where most things go.

What is a carcinogen?

A carcinogen is something that has the potential to cause cancer, usually by damaging our DNA or the way our cells work.

Carcinogens may occur naturally in the environment (such as ultraviolet rays in sunlight and certain viruses) or may be generated by humans (such as exhaust fumes and cigarette smoke).

It’s important to remember that the classification system rates how strong the evidence is (or how confident they are), not how dangerous something is.

That is why smoking cigarettes and eating processed meat are in the same category, not because they are equally dangerous but because IARC are equally confident they are linked to cancer. For example, processed meat causes around 5,400 cases of cancer every year in the UK, but smoking causes 54,000 cases.

Today, IARC have announced that aspartame is in group 2B. This means it is possibly carcinogenic, but there wasn’t enough evidence in humans to be sure. Why does it matter what the evidence shows in humans, what about evidence in animal studies?

While animal studies or studies on cells in labs can be useful, they cannot mimic real life scenarios.

For example, many studies on diet and cancer in mice expose them to much higher levels of a food or ingredient than a person could possibly eat in one day. This shows that a food may theoretically cause cancer, but doesn’t help when it comes to setting public health recommendations on what to eat – as someone would never be exposed to that much of one food.

Group 2B often shows that something can cause cancer in animals but hasn’t been able to show this in humans. For aspartame, there was no convincing evidence in humans or in animals.

So, when it comes to aspartame and other artificial sweeteners, what should we do? Some people choose to eat or drink artificial sweeteners instead of sugar because it could (theoretically) help them keep a healthy weight. However, the evidence for this is mixed. While food and drinks with artificial sweeteners do have less calories than food and drinks with sugar, there is no strong evidence that people who drink artificially sweetened drinks lose weight in the long run.

While we don’t know enough about artificial sweeteners and weight loss, what we do know is that eating a lot of sugar is linked to gaining weight and can make it harder to lose weight. Being overweight or obese increases the risk of 13 different types of cancer. So sugar can indirectly increase the risk of cancer through weight gain.

Following the announcement that aspartame would be classed as 2B, the Joint Expert Committee on Food Additives (JECFA) confirmed that there was no need to change the current acceptable daily intake. This is the amount of aspartame you can safely eat or drink each day, which is 40mg/kg of body weight. So, if someone weighed 70kg, they could drink 14 cans of diet cola and still be within the safe limit.

What should I eat and drink?

a plate filled with fruit, vegetables, fish and grains

The best thing you can do for your health is have a healthy balanced diet most days.

This means eating plenty of fruit and vegetables, fibre and wholegrains, and eating less foods high in fat, salt and sugar, and less processed and red meat. This doesn’t mean you can’t have something sweet sometimes!

So, if people eat food or have drinks containing aspartame, as part of a wider healthy balanced diet (that isn’t too high in sugar) there is no need to panic. As it is unlikely they would consume more than the daily limit that is considered safe.

The decision today puts aspartame in the same category as things like aloe vera and bracken ferns. There is no convincing evidence that it causes cancer in humans, and people shouldn’t be worried about getting cancer from aspartame in food and drink.

Your overall diet is more important than individual foods or ingredients for reducing cancer risk. So, aim to eat a healthy, balanced diet, with more fruit, veg and wholegrains, and cut back on red and processed meats and foods high in fat, sugar and salt.

- Dr Claire Knight, senior health information manager at Cancer Research UK

Comments

Chris

21 August 2023

Jane, you obviously did not read the article. It clearly does exactly as you request. “Following the announcement that aspartame would be classed as 2B, the Joint Expert Committee on Food Additives (JECFA) confirmed that there was no need to change the current acceptable daily intake. This is the amount of aspartame you can safely eat or drink each day, which is 40mg/kg of body weight. So, if someone weight 70kg, they could drink 14 cans of diet cola and still be within the safe limit.”

I would maybe add that drinking 14 cans of diet coke a day may have other side effects but I have no scientific data to back that up. Just going with my gut feeling (having just drunk 14 cans of diet coke).
Jane

22 July 2023

So many people don’t realise how often aspartame is added to everyday products. One small serving may do no harm. But what about multiple servings multiple times a week, or even a day?
The short answer may be “no” to the question “will eating or drinking aspartame give me cancer?” But short answers are dangerous to the vast majority of people who will not educate themselves further. Many want black and white clear cut rules, but it’s not that simple. What would be helpful perhaps, would be a gram per week suggestion; that way people could make sure they really are just getting a small amount.
A small amount in one product, may be harmless. But how many of those products are people consuming? Especially when these products will add marketing claims to packaging such as “low sugar”, “low fat”, “heart healthy” etc.

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Comments

Chris

21 August 2023

Jane, you obviously did not read the article. It clearly does exactly as you request. “Following the announcement that aspartame would be classed as 2B, the Joint Expert Committee on Food Additives (JECFA) confirmed that there was no need to change the current acceptable daily intake. This is the amount of aspartame you can safely eat or drink each day, which is 40mg/kg of body weight. So, if someone weight 70kg, they could drink 14 cans of diet cola and still be within the safe limit.”

I would maybe add that drinking 14 cans of diet coke a day may have other side effects but I have no scientific data to back that up. Just going with my gut feeling (having just drunk 14 cans of diet coke).
Jane

22 July 2023

So many people don’t realise how often aspartame is added to everyday products. One small serving may do no harm. But what about multiple servings multiple times a week, or even a day?
The short answer may be “no” to the question “will eating or drinking aspartame give me cancer?” But short answers are dangerous to the vast majority of people who will not educate themselves further. Many want black and white clear cut rules, but it’s not that simple. What would be helpful perhaps, would be a gram per week suggestion; that way people could make sure they really are just getting a small amount.
A small amount in one product, may be harmless. But how many of those products are people consuming? Especially when these products will add marketing claims to packaging such as “low sugar”, “low fat”, “heart healthy” etc.

Cancer News

Aspartame and cancer – sweet nothings?

What is aspartame?

Who are IARC and what is their rating system?

What is a carcinogen?