We came across this claim on local chat groups recently. Along with a video that goes into further detail, the claim is that starving cancer cells of sugar will cause them to die. We have also seen this claim being circulated on social media sites.

The individual in the video asserts that cancer “loves” sugar and glucose, recommending a specific 6-week minimum sugar fast to successfully starve cancer cells as an alternative treatment for the disease.

We found the original video on Youtube, titled “Cancer causes and treatment – Barbara O’Neil.” The video was uploaded in 2021 and has over 300 thousand views. Another search on different social media platforms shows that this video has been clipped and edited by different posters and kept in circulation on those platforms since 2021.Cancer refers to a group of diseases characterised by abnormal cell growth when genes mutate. These cancerous cells grow rapidly, cluster into tumours and can have extremely serious or fatal symptoms. The rapid growth of cancer cells further means more glucose (the form of sugar used by the human body as fuel) is consumed than ordinary cells.

While it is therefore true that all cells – both healthy and cancerous – require glucose, it is a huge oversimplification to claim that starving cancerous cells through a sugar fast is possible.

For one, it is not possible to only starve cancer cells; healthy cells being starved of glucose are likely to have impaired function, potentially leading to other health complications. Further, as noted in a fact-check from earlier this year by Science Feedback, “starving” cancer cells by not consuming glucose does not prevent them from accessing it – when faced with a lack of glucose, the body converts protein and fat into glucose instead through gluconeogenesis, which can lead to malnutrition and muscle loss.

There has been no scientific evidence that withholding sugar can cure cancer – nor could we find any attempts to study this as a cancer treatment. Published studies which have considered diet-based treatments have only mooted their potential as an accompanying strategy alongside established drug-treatments.

This claim oversimplifies the basic premise that cancer cells need glucose to grow and advocates an unproven and potentially harmful cancer “treatment.” Therefore, we give this claim a rating of false.

The claims of Barbara O’Neill, who is an “alternative medicine personality” have been fact-checked multiple times by different fact-checking outlets and health organisations – from unorthodox cancer treatments (such as baking soda), to discouraging the use of antibiotics. However, the videos featuring her health talks remain widely available on Youtube and are frequently used by other posters on social media as an authoritative voice on alternative health treatment. The convincing and simple nature of her logic and treatment suggestions can appear both compelling and convincing.

While misinformation about cancer cells and sugar has been pushed by other individuals, O’Neill specifically dispenses treatment advice (such as recommending a 6-week abstinence from sugar). This is extremely dangerous, as audiences who are searching for solutions to serious health issues are particularly vulnerable to such misinformation. It is vital to carefully fact-check claims such as this and consult medical professionals outside of social media before turning to alternative or unorthodox remedies.