Sweeteners may be linked to increased cancer risk – new research

Apr 13, 2022

4 min



Sweeteners have long been suggested to be bad for our health. Studies have linked consuming too many sweeteners with conditions such as obesity, type 2 diabetes and cardiovascular disease. But links with cancer have been less certain.


An artificial sweetener, called cyclamate, that was sold in the US in the 1970s was shown to increase bladder cancer in rats. However, human physiology is very different from rats, and observational studies failed to find a link between the sweetener and cancer risk in humans. Despite this, the media continued to report a link between sweeteners and cancer.


But now, a study published in PLOS Medicine which looked at over 100,000 people, has shown that those who consume high levels of some sweeteners have a small increase in their risk of developing certain types of cancer.


To assess their intake of artificial sweeteners, the researchers asked the participants to keep a food diary. Around half of the participants were followed for more than eight years.


The study reported that aspartame and acesulfame K, in particular, were associated with increased cancer risk – especially breast and obesity-related cancers, such as colorectal, stomach and prostate cancers. This suggests that removing some types of sweeteners from your diet may reduce the risk of cancer.


Cancer risk

Many common foods contain sweeteners. These food additives mimic the effect of sugar on our taste receptors, providing intense sweetness with no or very few calories. Some sweeteners occur naturally (such as stevia or yacon syrup). Others, such as aspartame, are artificial.


Although they have few or no calories, sweeteners still have an effect on our health. For example, aspartame turns into formaldehyde (a known carcinogen) when the body digests it. This could potentially see it accumulate in cells and cause them to become cancerous.


Our cells are hard-wired to self-destruct when they become cancerous. But aspartame has been shown to “switch off” the genes that tell cancer cells to do this. Other sweeteners, including sucralose and saccharin, have also been shown to damage DNA, which can lead to cancer. But this has only been shown in cells in a dish rather than in a living organism.



Sweeteners can also have a profound effect on the bacteria that live in our gut. Changing the bacteria in the gut can impair the immune system, which could mean they no longer identify and remove cancerous cells.


But it’s still unclear from these animal and cell-based experiments precisely how sweeteners initiate or support cancerous changes to cells. Many of these experiments would also be difficult to apply to humans because the amount of sweetener was given at much higher doses than a human would ever consume.


The results from previous research studies are limited, largely because most studies on this subject have only observed the effect of consuming sweeteners without comparing against a group that hasn’t consumed any sweeteners. A recent systematic review of almost 600,000 participants even concluded there was limited evidence to suggest heavy consumption of artificial sweeteners may increase the risk of certain cancers. A review in the BMJ came to a similar conclusion.


Although the findings of this recent study certainly warrant further research, it’s important to acknowledge the study’s limitations. First, food diaries can be unreliable because people aren’t always honest about what they eat or they may forget what they have consumed. Although this study collected food diaries every six months, there’s still a risk people weren’t always accurately recording what they were eating and drinking. Though the researchers partially mitigated this risk by having participants take photos of the food they ate, people still might not have included all the foods they ate.


Based on current evidence, it’s generally agreed that using artificial sweeteners is associated with increased body weight – though researchers aren’t quite certain whether sweeteners directly cause this to happen. Although this recent study took people’s body mass index into account, it’s possible that changes in body fat may have contributed to the development of many of these types of cancers – not necessarily the sweeteners themselves.


Finally, the risk of developing cancer in those who consumed the highest levels of artificial sweeteners compared with those who consumed the lowest amounts was modest – with only at 13% higher relative risk of developing cancer in the study period. So although people who consumed the highest amounts of sweetener had an increased risk of developing cancer, this was still only slightly higher than those with the lowest intake.


While the link between sweetener use and diseases, including cancer, is still controversial, it’s important to note that not all sweeteners are equal. While sweeteners such as aspartame and saccharin may be associated with ill health, not all sweeteners are. Stevia, produced from the Stevia rebaudiana plant, has been reported to be useful in controlling diabetes and body weight, and may also lower blood pressure. The naturally occurring sugar alcohol, xylitol, may also support the immune system and digestion. Both stevia and xylitol have also been shown to protect from tooth decay, possibly because they kill bad oral bacteria.


So the important choice may be not the amount of sweetener you eat but the type you use.

You might also like...

Check out some other posts from Aston University

3 min

Aston University optometrist develops app with the best easy blinking exercises to improve dry eye symptoms

Dry eye disease is a common condition affecting one-third of the adult population and one-in-five children Professor James Wolffsohn researched the most effective blinking exercises to reduce discomfort, involving a close-squeeze-blink cycle He developed the MyDryEye app in collaboration with Alec Kingsnorth and Mark Nattriss to help sufferers An Aston University optometrist, Professor James Wolffsohn, has determined an optimum blinking exercise routine for people suffering with dry eye disease, and has developed a new app, MyDryEye, to help them complete the routine to ease their symptoms. Dry eye disease is a common condition which affects one-third of the adult population and one-in-five children, in which the eyes either do not make enough tears, or produce only poor-quality tears. It causes the eyes to become uncomfortable, with gritty- or itchy-feeling eyes, watery eyes and short-term blurred vision. It is more common in older adults and can be exacerbated by factors including dry air caused by air conditioning, dust, windy conditions, screen use and incomplete blinks, where the eye does not fully close. Professor Wolffsohn is head of Aston University’s School of Optometry and a specialist in dry eye disease. While it has long been known that blinking exercises can ease the symptoms of dry eye disease, the optimum technique, number of repetitions and necessary repeats per day are unclear. Professor Wolffsohn set out to determine the best exercises. His team found that the best technique for a dry eye blinking exercise is a close-squeeze-blink cycle, repeated 15 times, three times per day. Participants found that while they were doing their exercises symptom severity and frequency decreased, and the number of incomplete blinks decreased. Within two weeks of stopping the exercises, their symptoms returned to normal levels, showing the efficacy of the exercises. To carry out the work, Professor Wolffsohn’s team ran two studies. For the first, they recruited 98 participants, who were assessed for dry eye symptoms before and after the two weeks of blinking exercises. Participants were randomly allocated different blinking exercises to determine the most effective. A second study with 28 people measured the efficacy of the blinking exercise. Once the optimum blinking routine had been developed, Professor Wolffsohn worked withAlec Kingsnorth, an engineer and former Aston undergraduate and PhD student, and Mark Nattriss, business manager of his spin-out company, Wolffsohn Research Ltd, to develop the app, MyDryEye, which is freely available on Android and iOS operating systems. The app allows users to monitor their dry eye symptoms, assess their risk factors, add treatment reminders and monitor their compliance, complete the science-based blink exercises and find a specialist near them. Professor Wolffsohn says that the blinking exercises should be carried out as part of a treatment programme which could also include the use of lipid-based artificial tears, omega-3 supplements and warm compresses. Professor Wolffsohn said: “This research confirmed that blink exercises can be a way of overcoming the bad habit of only partially closing our eyes during a blink, that we develop when using digital devices. The research demonstrated that the most effective way to do the exercises is three times a day, 15 repeats of close, squeeze shut and reopen – just three minutes in total out of your busy lifestyle. To make it easier, we have made our MyDryEye app freely available on iOS and Android so you can choose when you want to be reminded to do the exercises and for this to map your progress and how it affects your symptoms.” Read the full paper, ‘Optimisation of Blinking Exercises for Dry Eye Disease’, in Contact Lens and Anterior Eye at https://doi.org/10.1016/j.clae.2025.102453.

2 min

Aston University researchers to take the first steps to find out if AI can help policymakers make urban mobility more sustainable

Researchers to explore how AI can help urban mobility planners They are to investigate AI-driven policy tools’ potential to create greener cities Project to benefit from expertise of five European universities. A European group of researchers led by Aston University is taking the first steps to explore how AI can help urban mobility planners. As city populations grow causing strain on resources, the experts are to investigate AI-driven policy tools’ potential to create greener cities. The team have received £10,000 in funding from the British Academy which they hope will set them on the road to further research. Taking part in the project will be experts from University College London, Ruralis University in Norway, the University of Turin, Italy and Lisbon University Institute, Portugal. Dr Dalila Ribaudo from the Centre for Business Prosperity at Aston Business School and Dr Alina Patelli from the Aston Centre for Artificial Intelligence Research and Application will co-lead a UK-EU consortium consolidation project. The interdisciplinary project will benefit from expertise in applied business and specialist insight into global economics, policymaking and urban transport planning. Dr Patelli said “Policymakers and society could all benefit from our research into innovative ways of managing the strain on urban infrastructures and resources. "The AI-powered policy tools we are developing are meant to support decision managers at all levels of urban governance with reducing emissions, optimising transportation as well as predicting and preventing environmental hazards. Such changes would improve the quality of life for the millions of people living in towns and cities across the UK, Europe and, in the long term, the entire world.” Following the successful bid for the British Academy pump priming grant the team will apply for Horizon Europe funding to continue developing impactful AI-driven policy tools for greener cities.

3 min

New Aston University spin-out company will develop novel ways to treat non-healing wounds

EVolution Therapeutics (EVo) has been founded on the work of Professor Andrew Devitt into the causes of inflammatory disease A failure to control inflammation in the body, usually a natural defence mechanism, can cause chronic inflammation, such as non-healing wounds Non-healing wounds cost the NHS £5.6bn annually, so there is a vital need for new treatments. Aston University’s Professor Andrew Devitt, Dr Ivana Milic and Dr James Gavin have launched a new spin-out company to develop revolutionary treatments to treat chronic inflammation in patients. One of the most common inflammatory conditions is non-healing wounds, such as diabetic foot ulcers, which cost the NHS £5.6bn annually, the same cost as managing obesity. Such wounds are generally just dressed, but clinicians say there is a vital need for active wound treatments, rather than passive management. The spin-out, Evolution Therapeutics (EVo), will aim to create these vital active treatments. Inflammation in the human body helps to fight infection and repair damage following injury and occurs when the immune system floods the area with immune cells. Normally, this inflammation subsides as the damage heals, with the immune system signalling to the immune cells to leave. However, in some cases, the usual healing mechanism is not triggered and the inflammatory response is not turned off, leading to chronic inflammation and so-called inflammatory diseases. EVo is based on Professor Devitt’s work on dying cells in the body, known as apoptotic cells, and how they contribute to health. Dying cells release small, membrane-enclosed fragments called extracellular vesicles (EVs), which alert the immune system to the death of cells, and then trigger the body’s natural repair mechanism and remove the dead cells. It is estimated that 1m cells die every second. Professor Devitt and his team have identified the molecules within the EVs which control the healing process and are engineering new EVs loaded with novel healing enzymes, to drive the body’s repair responses to actively heal wounds. Much of the research has been funded by the Biotechnology and Biological Sciences Research Council (BBSRC) with additional support from the Dunhill Medical Trust. Professor Devitt, Dr Milic and Dr Gavin received Innovation-to-Commercialisation of University Research (ICURe) follow-on funding of £284,000 to develop the vesicle-based therapy with EVo. Most recently, in December 2023, Professor Devitt and Dr Milic were awarded £585,000 from the BBSRC Super Follow-on-Fund to develop engineered cells as a source of membrane vesicles carrying inflammation controlling cargo. The team, together with Professor Paul Topham, also received funding from the National Engineering Biology Programme (£237,000) to support polymer delivery systems for vesicles. EVo is one of the 12 projects being supported by SPARK The Midlands, a network which aims to bridge the gap between medical research discoveries of novel therapeutics, medical devices and diagnostics, and real-world clinical use. SPARK The Midlands is hosted at Aston University, supported by the West Midlands Health Tech Innovation Accelerator (WMHTIA), and was launched at an event on 31 January 2024. Professor Devitt, EVo chief technical officer, said: “Inflammation is the major driver of almost all disease with a huge contribution to those unwelcome consequences of ageing. We are now at a most exciting time in our science where we can harness all the learning from our research to develop targeted and active therapies for these chronic inflammatory conditions.” Dr Gavin, EVo CEO, said: “The chronic inflammation that results in non-healing wounds are a huge health burden to individuals affecting quality of life as we age but also to the economy. Our approach at EVo is to target the burden of non-healing wounds directly to provide completely novel approaches to wound care treatment. By developing a therapy which actively accelerates wound healing, we hope to drastically improve quality of life for patients, whilst reducing the high cost attached to long term treatment for healthcare systems worldwide.”

View all posts