Nutritionist settles debate on only 2 foods that cause cancer not sugar

A nutritionist has highlighted the only two foods scientifically proven to cause cancer, with her guidance supported by leading organisations including the World Health Organisation (WHO) and Cancer Research UK. She has also debunked the common misconception that sugar causes cancer.

The WHO classifies both these foods as "group 1 carcinogens". According to WHO guidelines, a substance receives this classification when "there is convincing evidence that the agent causes cancer". Of course, this doesn't mean you will definitely get cancer if you consume them.

Multiple authoritative sources confirm that just two foods are definitively linked to cancer: processed meats and alcohol. The WHO also places tobacco smoking and asbestos in the group 1 carcinogen category. Importantly, the organisation emphasises that alcohol and processed meat don't pose equivalent dangers to smoking and asbestos. These classifications reflect the robustness of scientific evidence linking an agent to cancer, not the actual risk level, reports WalesOnline.

Regarding processed meats, the WHO states: "This classification is based on sufficient evidence from epidemiological studies that eating processed meat causes colorectal cancer."

Regarding alcohol consumption, the WHO states "there is no safe amount that does not affect health". It highlights that alcohol "has been classified as a group 1 carcinogen by the International Agency for Research on Cancer decades ago this is the highest risk group, which also includes asbestos, radiation and tobacco" and notes "alcohol causes at least seven types of cancer, including the most common cancer types, such as bowel cancer and female breast cancer".

Alcohol is also considered a group 1 carcinogen and leading health experts have warned there is no safe amount to drink (Image: Getty) Processed meat is classified as a 'group 1 carcinogen' (Image: Getty)

Nichole Andrews, a registered dietitian nutritionist who refers to herself online as "the oncology dietician" due to her expertise in connections between cancer and diet, states: "There are only two foods that you eat... that increase your cancer risk."

Identifying alcohol and processed meats, she adds: "That is it, that's the full list."

Writing on her Instagram account, Nichole clarifies: "As a cancer dietician, let me clarify: sugar all on its own will not cause cancer... If you have a diet high in sugar, you're probably going to have excess calories... and then you're going to gain weight, gain fat tissue and it's the fat tissue that increases cancer risk. Eating sugar in moderation is OK. It's excess calorie intake (from any food) that leads to weight and fat gain, which increases cancer risk."

She stresses that the "real risks" are alcohol and processed meats. Cancer Research UK echoes this guidance, stating: "We know for definite that processed meat is a cause of cancer. We are as sure of this link as we are for other proven causes of cancer, like tobacco and alcohol."

Why does alcohol cause cancer?

Alcohol causes cancer because of how it breaks down in the body. This means that any drink containing alcohol, regardless of its price, quality or strength, poses a risk of developing cancer.

The WHO states there is no safe amount of alcohol to drink, which goes against reports you may have heard that a small amount of alcohol can be good for you (this does not mean that certain alcoholic drinks don't have some health benefits, for example, via the polyphenols in red wine).

The WHO notes that cancer risk "increases substantially the more alcohol is consumed" but that "latest available data indicate that half of all alcohol-attributable cancers... are caused by 'light' and 'moderate' alcohol consumption less than 1.5 litres of wine or less than 3.5 litres of beer or less than 450 millilitres of spirits per week". Alcohol is linked to at least seven cancer types, including the most prevalent forms, such as bowel cancer and female breast cancer.

And Dr Ernest Hawk, the vice president and head of the division of Cancer Prevention and Population Sciences at the University of Texas MD Anderson Cancer Center, told the New York Times: "There is no safe level of alcohol when it comes to cancer risk."

Why does processed meat cause cancer?

Research has identified three meat-related chemicals linked to heightened bowel cancer risk. These chemicals occur naturally in meat, are introduced during processing, or form during cooking. Cancer Research UK states that all three can harm cells in the bowel, with the build-up of this damage over time raising cancer risk.

What is processed meat?

The World Health Organisation defines processed meat as "meat that has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation". Most processed meats contain pork or beef, though they may also include other red meats, poultry, offal, or meat by-products such as blood. The organisation provides the following examples of processed meat:

• hot dogs (frankfurters)
• ham
• sausages
• corned beef
• biltong or beef jerky
• canned meat
• meat-based preparations and sauces.

Cancer Research explains that chemicals present in processed meat, introduced during processing or created when cooking, include nitrates and nitrites, which help keep processed meat fresher for longer. It adds: "When we eat them, nitrates and nitrites can become N-nitroso chemicals (NOCs) that can damage the cells that line our bowel. This damage can lead to bowel cancer."