According to World Cancer Research, one in two people in the UK will get cancer in their lifetime. And, with cancer cases rising, it’s only natural that many of us want to know why.
Experts have identified several potential causes of cancer. Some of these, such as the role of lifestyle choices like diet and smoking, we understand, while others remain somewhat unexplained.
While we don’t yet have all the answers, the good news is that there are several known ways to help reduce your risk of cancer. Here, we’ll take a closer look at what the current research says.
What is cancer?
Our bodies are made up of more than a hundred million cells. When everything is functioning as it should, we have just the right amount of each cell type. According to Cancer Research, cancer starts when genes (DNA) within cells change, causing them to divide and grow in an uncontrolled way, and develop into a tumour.
There are over 200 different cancer types. Experts divide these into five main cancer groups, categorised by the type of cell they start from. These are…
- Carcinomas
- Lymphomas
- Leukaemias
Brain and spinal cord cancers
- Sarcoma
What can cause cancer?
As we’ve said, cancer is caused by changes to DNA cells, also known as mutations. Experts understand why some of these changes occur, but other times, it’s not so clear.
Below, we’ll explore what current research into the causes of cancer says.
Note: It’s important to note that having one or more risk factors doesn’t necessarily mean you’ll get cancer. Some factors only slightly increase your risk, and it’s still possible to develop cancer even if you don’t have any known risk factors.
Genetics
In some cases, cancer-related gene changes (mutations) can be inherited, increasing a person’s risk of developing cancer during their lifetime. Examples of cancers that can be genetically inherited include breast cancer and colon cancer.
That said, studies suggest only 5-17% of all cancer cases are attributed to genetic mutations, with lifestyle and environmental factors, such as a poor diet, playing a larger role.
Smoking
Smoking is considered the biggest cause of cancer in the UK, responsible for 15% of all cancer cases – including 72% of lung cancers.
Tobacco smoke contains over 60 different toxic substances confirmed to be carcinogenic (cancer-producing), including nicotine. We also know from data that the more you smoke, the higher your risk. For example, smoking 25 cigarettes a day makes you 25 times more likely to develop lung cancer than someone who doesn’t smoke.
Being overweight
Being overweight is the second biggest cause of cancer and is closely linked with several types, including bowel, kidney, womb, and oesophagus cancer.
According to research, the risk for breast cancer specifically increases for menopausal women who are overweight.
Sun damage
Spending time outdoors in the sun is a great way to reduce stress, stay active, and get a healthy dose of vitamin D. However, overexposure to the sun’s UV rays can cause sunburn, heat stroke, premature ageing, and increase the risk of skin cancer.
For example, melanoma skin cancer is the fifth most common cancer in the UK and is primarily caused by sun damage.
Poor diet
As well as contributing to weight gain, poor diet choices can increase the risk of certain health conditions – including cancer. In fact, the World Cancer Research Fund (WCRF) estimates that between 30% and 50% of all cancer cases could be prevented if people had healthier diets and lifestyles.
Beyond general diet gaps, such as not eating enough fibre, the World Health Organization (WHO) has highlighted several ‘carcinogenic’, or cancer-causing, foods (a carcinogen is a substance capable of causing cancer in living tissue). Among these are alcohol, fast food, and processed meat like ham, corned beef, and frankfurter hotdogs.
For example, alcohol, a classified Group 1 carcinogen, is specifically linked with an increased risk of throat, mouth, liver, breast, and bowel cancer.
Air pollution
Air pollution has been linked with a greater risk of several cancers, including lung cancer, liver cancer, and breast cancer.
According to experts, air pollution is most common in areas with a high amount of motor vehicle exhaust, fuel is burned for power generation, and rubbish is regularly burned.
Age
Age is a risk factor for cancer because cells become more susceptible to genetic mutations over time. For example, according to statistics, the median age of breast cancer, prostate cancer, and lung cancer diagnoses is 62, 66, and 71, respectively.
That said, experts say a person’s cancer risk can be reduced by making healthy lifestyle choices.
Infections
Certain infections can increase the risk of cancer. For example, according to Cancer Research, nearly all cases of cervical cancer are caused by human papillomavirus (HPV).
HPV is a common virus that infects skin cells lining the body, including the mouth, throat, and genitals. It’s also linked with an increased risk of some types of head and neck cancer.
Note: The HPV vaccine helps to prevent cancer by protecting against HPV.
Household chemicals
There have been recent concerns raised around the potential link between certain household items, including mattresses, cleaning products, and nonstick cookware, and cancer risk.
For example, one study suggested that certain household cleaning products could expose us to potentially harmful chemicals, like benzene, which have been linked to cancer.
Note: Research into the link between certain household products and cancer is ongoing, and further studies are needed before a conclusion can be reached. You can read more about current research into cancer concerns from everyday products on the Harvard Health website.
7 ways to reduce your risk of cancer
The prevalence of cancer these days, and the fact that cases are rising, can feel frightening. However, while it’s not possible to eliminate your risk, there’s reason to be encouraged. According to experts at Macmillan Cancer Support, around 40% of cancers could be prevented with lifestyle changes.
We’ll explore some of the main ways you can reduce your risk below.
1. Take steps to quit smoking
Smoking is the biggest cause of cancer, so quitting is the single most important thing you can do for your health.
Even if you’ve smoked for years, it’s never too late to quit. Research from Macmillan Cancer Support shows that after 12 years of not smoking, a person’s lung cancer risk is about 72% lower than it is for those who still smoke; and after about 15 years, it’s almost the same as someone who has never smoked.
If you’d like help giving up smoking, you might find our article, 7 tips for quitting smoking, useful.
It’s also worth noting that, while cigarettes pose the largest risk, other tobacco products, such as cigars, chewing tobacco, and cannabis (because most people mix it with tobacco), also increase cancer risk.
2. Maintain a healthy weight
Cancer Research advises that maintaining a healthy weight is one of the best ways to reduce your cancer risk.
Simple steps like increasing your daily step count, improving your diet, and engaging in physical activity can make all the difference when it comes to dropping excess weight.
If you struggle to lose weight or find yourself in a constant cycle of yo-yo dieting, you might find our article, 7 tips to lose weight and keep it off, useful.
3. Enjoy the sun safely
Sun damage is the biggest cause of skin cancer, but the good news is it’s also one of the most preventable. Experts at Cancer Research UK estimate that up to nine in 10 cases of melanoma skin cancer could be prevented if people enjoyed the sun safely.
For this reason, taking steps to protect your skin from sun damage, such as wearing sunscreen every day (no matter the weather), can make all the difference to your risk.
Using sunbeds or sunlamps is also linked with an increased risk of skin cancer. If you’d like to look tanned, it’s best to use fake tan lotions or sprays instead.
4. Eat a balanced diet and avoid carcinogenic foods
Eating a healthy, balanced diet full of essential nutrients like fibre, protein, vitamins, and minerals is key to reducing cancer risk. For example, studies suggest that around 28% of bowel cancer cases in the UK are caused by eating too little fibre.
Similarly, it’s important to restrict your intake of ‘carcinogenic’ foods, such as alcohol and processed meat.
5. Introduce cancer-fighting foods
There’s evidence that certain foods, including carrots, beans, berries, and flaxseed, may be particularly beneficial for fighting cancer. This is largely due to the presence of plant compounds, like polyphenols, which have antioxidant properties.
For example, an analysis of five different studies found that eating carrots reduced the risk of stomach cancer by up to 26%. And another animal study found that rats had a 75% lower risk of cancer when they were fed black beans.
To learn more, check out our article: Which foods might increase or decrease the risk of cancer? Alternatively, head over to our diet and nutrition section for more diet tips.
6. Attend cancer screenings
The UK currently has three national cancer screening programmes for breast, cervical, and bowel cancer.
Cancer screenings are designed to promote early cancer diagnosis by detecting potential signs of cancer in people with no symptoms. We know from research that early diagnosis can make all the difference to cancer outcomes. For example, statistics from Cancer Research UK show that almost 100% of people will survive Stage 1 breast cancer for five years or more if it’s caught early enough.
For this reason, attending cancer screenings is one of the best things you can do to protect your health.
Other regular health checks, such as cholesterol testing and blood pressure checks, are also helpful for assessing overall health and risk of health conditions, including cancer.
It’s important to note that, while there aren’t national screening programmes for all types of cancer, there are tests available. For example, PSA tests can be used to check for prostate cancer, which is the most common cancer in men. To learn more, check out our article: 8 myths about prostate cancer testing that could be putting you at risk.
Note: If something doesn’t look or feel right, it’s important to speak to your GP as soon as possible. Don’t wait for the screening.
7. Be aware of body changes
Alongside attending regular cancer screenings and health checks, it’s helpful to familiarise yourself with the potential signs of cancer.
Interestingly, experts at Cancer Research UK say there’s no solid evidence that home ‘self-examinations’, which involve regularly checking at a set time in a very specific way (such as using certain hand movements or positions), are useful. Among other things, they say these checks often lead to unnecessary tests, treatment, and worry.
Instead, being ‘body aware’ by knowing what your body usually looks and feels like can make it easier to spot any changes that aren’t normal for you. For example, noticing breast or mole changes.
Final thoughts…
Considering one in two of us will develop cancer, it’s natural to want to know what we can do to reduce our risk. While further research is needed to fully understand how and why cancer develops, there are things we can do to take charge of our health and reduce our risk.
For further reading, head over to our general health section.
Do you have any other insights that you’d like to share? We’d be interested to hear from you in the comments below.
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