An illustration with text that reads "7 common cancer myths, unpicked".

Google the word ‘cancer’ and millions of results will appear.

Like anything on the internet, some will lead to useful, accurate information, while others will be inaccurate, or even dangerously misleading.

Often, it can be hard to distinguish fact from fiction. Much of the inaccurate information can look and sound perfectly plausible. But if you scratch the surface a little, many continually perpetuated ‘truths’ become unstuck.

From 5G to sharks with cancer, we want to set the record straight with 8 commonly asked questions about cancer that are often rooted in misinformation.

1. Can 5G or Wi-Fi cause cancer?

An illustration of a wifi mast and wifi router. After evaluating the best scientific evidence, there are no good explanations for how 5G mobile could cause cancer.

You may have heard the myth that 5G networks emit radiation that can damage our DNA and cause cancer. But when it comes to radiation, the amount of energy released is what matters. Whilst it’s true that 5G networks transmit radio frequency radiation (radio waves), it’s not the kind that can cause cancer.

Higher energy radiation (often called ionising radiation), such as UV rays from the sun, releases enough energy to damage DNA. But both 4G and 5G networks transmit radio frequency radiation (radio waves), which is very weak (non-ionising). This means that it does not have enough energy to damage DNA and there is no direct way it can cause cancer.

4G and 5G do use higher frequency waves than older mobile networks, but they still don’t have enough energy to damage DNA and cause cancer. Mobile phones, phone masts and Wi-Fi also rely on the same, non-ionising radiation.

You may have come across alarming headlines in the past linking mobile phones to cancer. But these are often based on studies carried out on cells or rats in a lab.

These types of studies often use doses of radiation that are far higher than those emitted by mobile phones and over a much longer period of time than people would ever be exposed to in real life.

There is also occasionally speculation that Wi-Fi can cause cancer, but again this isn’t supported by evidence. Radio waves produced by Wi-Fi are very low energy. They are even weaker than those produced by mobile phones, and well within international guidelines that the UK adheres to.

As 5G and 4G, mobile phones and Wi-Fi are still relatively new technologies, research is on-going. We can’t completely rule out long-term effects and we will continue to monitor the evidence in the future.

But overall, there’s no good evidence of a link with cancer.

2. Do microwaves cause cancer?

An illustration of a microwave heating food.Just like the radio waves used by mobile phones, microwave radiation is non-ionising.

This means the radiation is too weak to damage DNA and it can’t directly cause cancer.

Despite some common misconceptions, microwaves do not make your food radioactive and it’s safe to stand in front of the microwave oven when it’s on.

When it comes to cancer risk, what you eat, not how you heat it up, is what matters.

To reduce your cancer risk, a healthy, balanced diet is more important than individual foods. This includes eating fruit and vegetables, wholegrains (like brown rice or brown pasta) and healthy sources of protein (like beans, lentils or fresh chicken), whilst reducing your intake of processed and red meat, and foods high in sugar, fat and salt.

3. Can an acidic diet cause cancer and can an alkaline diet cure cancer?

An illustration of a series of test tubes showing different pH.Some research may have misled people to believe this is true but acidic diets, which includes eating things like meat and eggs, won’t cause cancer and alkaline diets, high in green vegetables and fruit, can’t cure it.

While lab research on cells has shown that acidic environments can help cancer cells to grow, this doesn’t reflect how cancer cells would behave in the human body, which is much more complex.

However, this research has led to false information spreading that very ‘acidic’ diets can increase cancer risk. And, on the other side of this coin, that foods high in ‘alkaline’ can prevent or even cure cancer.

If this were true, it would mean that what we eat could change our body’s levels of acid, also known as our pH levels. But this isn’t possible as our pH levels have to be tightly regulated within a certain range to keep us alive.

It’s our kidneys’ job to make sure our pH levels stay within a very strict and narrow healthy range. What you eat can’t change this for a meaningful amount of time, and any extra acid or alkali from your food comes out in your pee.

And, although it’s the case that cancer cells can’t live in a very alkaline environment, neither can any of the other cells in our body.

Put simply – there’s no good evidence to prove that diet can manipulate whole body pH, or that it has an impact on cancer.

Other myths – does sugar feed cancer?

These 7 examples are not a finite list of cancer myths.

  • There are lots of myths surrounding sun safety, read our ‘11 sun safety myths debunked’ to find out more.
  • There’s a lot of confusing information and advice out there around sugar, our updated article on sugar and cancer aims to answer some of these confusing questions.
  • Read more for 10 things you might not know about alcohol and cancer.
  • Cannabis and cancer causes quite a debate online, so we’ve collated the evidence so far.

4. Does the cure for cancer already exist?

An illustration showing a bottle of cancer drugs with a lock on the lid. Animals were developing cancer long before humans have inhabited the earth, and the world’s oldest documented case of cancer in humans hails from ancient Egypt in 1500 BC.

Some people may assume that, after all this time, a cure must exist.

But the reality is that cancer is extremely complex. And despite decades of amazing research, there is no ‘silver bullet’ that will cure all cancers. Cancer comprises over 200 different diseases, and each will be treated differently.

While there’s no ‘one-size-fits-all’ answer to curing cancer, we have made real progress. In the 119-year history of the charity alone, we have significantly improved outcomes for people with cancer. Even in the last 40 years, survival has doubled thanks to research into more effective and gentle treatments, improving diagnostic techniques and campaigning for policy change.

It’s worth pointing out that the definition of a cancer cure varies depending on who you speak to. The word ‘cure’ might typically be associated with a cancer disappearing and never coming back. But it is far more nuanced than that as sadly, people’s cancers do come back. For lots of the statistics we use, we refer to cancer ‘survival’ instead. Although the terms may be similar, cancer survival refers to the percentage of people still alive after a specified amount of time, often 1, 5 or 10 years after their diagnosis.

And when it comes to these so-called ‘miracle cures’, many seem to stem from food, or herbal medicines. The appeal of these products is completely understandable. However, our advice is to be wary of anything labelled a ‘miracle cure’, especially when people are trying to sell it to you. Wikipedia has a list of disproven cancer treatments that are often touted as miracle cures.

This doesn’t mean that the natural world isn’t a great source of potential treatments. In fact, the cancer drug taxol was first extracted from the bark and needles of the Pacific Yew tree.

Hand in hand with the idea of ‘miracle cures’ is the belief that governments, the pharmaceutical industry and even charities are hiding the cure for cancer because they make money off existing treatments.

We understand that there are some frustrations around transparency within the pharmaceutical industry. We advocate for regulators, health technology assessment (HTA) bodies, and pharmaceutical companies to make sure that effective drugs are made available quickly and at a fair price to the NHS. Although it’s important to remember that developing and trialling new drugs costs a lot of money, which companies need to recoup.

And the reality is that finding a highly effective therapy would actually guarantee huge worldwide sales for any pharmaceutical company.

What’s more, charities and government-funded scientists are free to investigate promising treatments without a profit motive.

Finally, it’s worth remembering that we’re all human. Cancer can affect anyone, from politicians to Big Pharma executives. People who work in pharmaceutical companies, governments and charities can all get cancer too, and we’re all working towards a common goal – to help beat it.

5. Does cancer treatment kill faster than it helps?

An illustration of a sandglass clock.The reason any cancer treatment is offered is to give someone the best chance at controlling their disease. But the reality is that the side effects of cancer treatment can often be really tough. After all, treatments that are designed to kill cancer cells will affect healthy cells to some extent too.

Every licensed treatment has been through rigorous clinical trials to ensure that the treatment is safe, effective and to understand its side effects.

But sometimes, sadly, treatment doesn’t work. We know that it’s very difficult to treat late-stage cancer that’s spread throughout the body. And while treatment can provide relief from symptoms and prolong life, it’s very difficult to find a cure for very advanced cancers.

This kind of question tends to arise in relation to chemotherapy, as the side effects can be particularly gruelling.

But chemotherapy and other cancer drugs still have a very important part to play in cancer treatment – in some cases helping to cure the disease and in others, helping people to spend longer, precious time with their loved ones.

Take children’s and young people’s cancer. More than 8 in 10 children and young people in the UK, aged 0 to 24, survive their cancer for 10 years or more. These achievements have been made possible by the development of treatments, including chemotherapy. Survival for children and young people hasn’t always been this high – in the 1970s, just over a third of children diagnosed with cancer in Great Britain survived for 10 years or more. These achievements have been made possible by the development of treatments, including chemotherapy.

But the other side is that treatment for children and young people can often have long-lasting, damaging side-effects. Increasing our understanding of the biology of children’s and young people’s cancers has led to significant changes to the way we treat children and young people with chemotherapy for the better, and researchers are always looking to reduce the toxicity of these treatments.

We know that side effects exist, and it’s an important conversation to have as part of your cancer journey. We also understand that we still have a long way to go until we have effective, kinder treatments for all types of cancer, and it’s something we’re striving for every day.

6. Is cancer a fungus and baking soda the cure?

An illustration of a packet of sodium bicarbonate being poured.It’s well understood that cancer begins due to faults (mutations) in our own cells.

We don’t know exactly where the theory that cancer is a fungus came from, but it’s a persistent one. The origin of this myth may stem from the idea that cancer is caused by infection from the common fungus candida, and tumours are actually the body’s attempt at protecting itself from this infection.

Some sources have suggested that baking soda (sodium bicarbonate) is an answer to treat cancer. Although sodium bicarbonate is not a solution that has been proven to treat known fungal infection, it is known that high doses of sodium bicarbonate can lead to very serious consequences.

Some studies suggest that sodium bicarbonate can affect cancers transplanted into mice or cells grown in the lab, by neutralising the acidity in the microenvironment immediately surrounding a tumour.

A small clinical trial, carried out some years ago in the US, was investigating whether sodium bicarbonate capsules can help to reduce cancer pain, but the trial didn’t progress to phase 2 with any results.

As far as we are aware, there have been no published clinical trials of sodium bicarbonate as a treatment for cancer.

7. Can sharks get cancer?

An illustration of a shark. Yes, they can.

This question stemmed from the discovery that cartilage can prevent a key process that allows cancers to spread, which is the formation of blood vessels (angiogenesis). Sharks’ skeletons are entirely made of cartilage.

Possibly, the reason people believed that sharks couldn’t get cancer is likely due to the fact that no one had done a systematic study to check whether they could. However, a study carried out in 2004, looking for cases of cancer in existing animal collections, found 42 tumours in the Chondrichthyes species – a class of cartilaginous fish that includes sharks, skates and rays, including cases of tumours in shark cartilage.

But while it looks like sharks can develop cancer, there is one animal that has a remarkable resistance to the disease – the naked mole rat.

Naked mole rats have an exceptional resistance to cancer, thanks to unique conditions in their bodies that stop cancer cells multiplying.

Understanding how these fascinating animals are almost completely immune to cancer could improve our understanding of the early stages of the disease in humans, and lead to new ways to prevent or better treat it.


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