Aspartame does not pose a cancer risk at current consumption levels, World Health Organization (WHO) officials ruled today.
The artificial sweetener added to Diet Coke has now been officially listed as ‘carcinogenic to humans’ following a major safety review.
But only those who consume excessive amounts face an elevated risk, a panel of experts concluded.
The current safe limit is set at 40mg per kg of body weight per day.
An 11st (70kg) adult would need to consume 14 cans of a diet soft drink containing 200mg of aspartame — such as Diet Coke — to exceed this limit.
At a briefing yesterday, WHO director of nutrition and food security Dr Francesco Branca said the WHO’s ‘fairly large’ daily acceptable limit meant there was no problem consuming this amount of aspartame ‘without appreciable health effects’.
UK products contain aspartame: Specialty products containing aspartame – which entered the market in the 1980s – include Diet Coke, Dr Pepper as well as extra chewing gum and Müller light yoghurt. Some toothpastes, dessert mixes and sugar-free cough drops also contain it
And a 3rd 2lb (20kg) child could, in theory, eat aspartame two to three times a day without risking it, the WHO said. However, the United Nations Health Organization notes this is ‘not good practice’.
Aspartame entered the market in the 80s, quickly adopted by food and beverage manufacturers amid a massive crackdown on sugar.
Specialty products with sweeteners include Dr. Pepper, Extra Chewing Gum, and Radish Light Yogurt.
Some toothpastes and sugar-free cough drops are also made with aspartame.
WHO chiefs confirmed that they had not called on producers or authorities to remove affected products from the market despite the ‘obvious’ reclassification.
But they urged manufacturers to consider product reformulation as sweeteners are ‘not the way forward’.
And people should still limit their consumption of sweeteners, urging people to switch to tap water.
Aspartame’s cancer reclassification was first leaked last month, in a decision that sent shockwaves through food manufacturing markets worldwide.
But at the time independent experts warned that the risk was blown out of proportion and that people would be tempted to change their eating habits unnecessarily.
Professor Günter Kuhnle, an expert in nutrition and food science at the University of Reading, told MailOnline: ‘The concern was overwhelming.
‘This is unfortunate, because aspartame (and other sweeteners) is a way to reduce sugar content while maintaining a sweet taste.
‘Using health scares and misinformation to persuade people to change their diet is, in my opinion, a rather unethical approach.’
Professor Tom Sanders, a dietetics expert at King’s College London, added: ‘I think it’s important to separate hypothetical risk from health risk.’
Today’s landmark WHO ruling comes from two separate subsidiary bodies.
Aspartame has been declared a probable carcinogen by the IARC, or International Agency for Research on Cancer.
Its decision was based on limited evidence gathered over the past two decades that it could be hepatocellular carcinoma – a type of liver cancer.
Over the years, some studies have suggested it is carcinogenic to animals and highlighted possible mechanisms to explain the link.
The IARC panel assessed the risk as 2B, meaning limited but not convincing evidence.
IARC grades the risk as 2B – meaning limited by lack of convincing evidence – putting it in the same category as gasoline engine exhaust fumes, lead and the occupational risks of being a hairdresser – with workers regularly exposed to the chemical.
US Products Containing Aspartame: The graphic above shows some of America’s favorite snacks that contain the sugar sweetener aspartame. Smint is a breath freshener sold in some parts of the United States
Aspartame in UK products: Thousands of products contain the artificial sweetener aspartame, from mouthwashes and vitamin gums to yoghurt and squash
Aspartame was placed in the same category as aloe vera, gasoline engine exhaust fumes, lead and the occupational hazards of being a hairdresser.
This ruling is only concerned with how strong the evidence is regarding a substance causing cancer, not how much of a risk it poses.
Instead, that specific question was left to the joint WHO and Food and Agriculture Organization Expert Committee on Food Additives (JECFA) to answer.
It concluded that there is no convincing evidence that aspartame can cause cancer when consumed within the limits already set by the WHO.
The experts said the decision was ‘probably because any new evidence is either not convincing enough or not relevant to the amount consumed by us’.
Professor Sanders added: ‘The hype over the safety of aspartame caused by the WHO press release earlier this month was a tempest in a teacup.’
By contrast, the dangers of sugar to health are ‘specific and real’, he told MailOnline. Excess sugar intake can lead to obesity and consequent complications and tooth decay.
Professor Naveed Sattar, an expert in metabolic medicine at the University of Glasgow, said he was ‘convinced’ by the verdict.
He added: ‘I feel comfortable advising relevant patients to switch from sugary drinks to diet drinks or ideally water as a way to reduce refined sugar intake.’
IARC and JECFA have called for more thorough research into the link between cancer and aspartame so that it can make stronger recommendations in the future.
Announcing the move, WHO director of nutrition and food security Dr Francesco Branca said the WHO’s ‘fairly large’ daily acceptable limit meant there was no problem consuming this amount of aspartame ‘without appreciable health effects’.
‘So definitely, WHO is not advising producers or authorities to withdraw products from the market,’ he added.
‘But given that there are some concerns identified by the research… we definitely recommend that consumers limit their consumption of sweeteners.’
Dr Branca said he would urge people to drink water instead of sugar or sweetened drinks, noting that a cancer risk from aspartame ‘can’t be dismissed at this point’.
He said health risks may begin for ‘high consumers’ and WHO findings suggest that occasional consumption of products containing aspartame will not pose a risk for most.
Dr Branca encouraged companies to reformulate products so they do not contain sweeteners, as the chemical is ‘not the way forward’ and does not cause any health benefits.
The British Nutrition Foundation told MailOnline that it welcomes the WHO publication ‘which adds clarity and reassurance to this area’.
Sir David Spiegelhalter, emeritus professor of statistics at Cambridge University, said the IARC reports were being ‘a bit farcical’.
‘As they’ve said for 40 years, the average person is safe to drink up to 14 cans of diet drink a day, which is about an old gallon – about half a large bucket. And even this “acceptable daily intake” has a large built-in safety factor,’ he added.
Aspartame – What You Need to Know
What is aspartame?
Aspartame is an artificial sweetener that was first developed in the 60s and is about 200 times sweeter than sugar.
This means that less sugar is needed per gram of sugar to get the same sweet result, while products that contain it have fewer calories overall.
Unlike sugar it does not raise blood sugar levels and thus can be used as an alternative source of sweeteners for diabetics.
Chemically it is composed of three substances aspartic acid (40 percent), phenylalanine (50 percent) and methanol (10 percent).
Is it available?
A variety of products market themselves as ‘diet’ or ‘sugar-free’.
The most famous examples are soft drink giant Coca-Cola’s diet sodas, Diet Coke and Coke Zero as well as sugar-free gums such as Extra.
Other examples include low-fat yogurt.
Does Coke Zero and Pepsi Max also have aspartame?
Yes. Both products list aspartame in their ingredients list.
Other soft drink brands such as some Fanta flavors, Lucozade and Dr. Pepper also contain artificial sweeteners.
What is the danger?
Aspartame has been linked to common medical problems including headaches, dizziness and upset stomach.
But blind trials, where participants don’t know whether the product they consume contains sweeteners, have failed to replicate this.
But over the years there have been widespread health concerns, including that they cause cancer, alter the gut biome, cause depression and even contribute to obesity by increasing human appetite.
However, health and food regulators have repeatedly declared them safe to use following ‘rigorous safety assessments’.
There is one exception, which is for people with phenylketonuria, a rare inherited condition.
People with phenylketonuria cannot process phenylalanine, an amino acid that is one of the building blocks of aspartame.
If people with phenylketonuria take phenylalanine, it can build up in their blood and eventually damage their vital organs.
This is why aspartame must be listed as an ingredient that contains it.
Only one in 10,000 people have the condition.