Recent research has revealed surprising links between our everyday food choices and cancer risk. It highlights often-overlooked foods that could significantly lower our chances of developing certain types of cancer.

A groundbreaking study by the American Cancer Society (ACS)[1] has found that about 40% of cancer cases and 50% of cancer deaths in adults over 30 could be prevented by addressing changeable lifestyle factors, including diet.

Let's explore these findings and see how simple changes to our meals could make a big difference to our health.

How Our Lifestyle Affects Cancer Risk

The ACS study, published in July 2024, offers valuable insights that likely apply to other developed countries, including the UK. It found that risk factors within our control, including diet, physical activity, and other lifestyle choices, play a crucial role in cancer prevention.

Dr. Farhad Islami, a senior researcher at the ACS who led the study, said: "Helping people maintain a healthy weight and diet can greatly reduce the number of cancer cases and deaths, especially since we're seeing more cancer types linked to excess weight, particularly in younger people."

This underlines why the foods we'll discuss below are so important in potentially reducing cancer risk by up to 40%.

Fibre: Your Gut's Best Friend

The ACS study found that excess body weight was the second biggest controllable factor in cancer cases, after smoking, contributing to 7.6% of all cancer cases. This shows how crucial it is to maintain a healthy weight, and fibre plays a big role in this.

The NHS recommends adults consume 30 grams of fibre per day. Fibre is thought to prevent colon cancer through several mechanisms:

1. Promoting more frequent bowel movements, reducing the time harmful chemicals spend in the bowel

2. Potentially binding carcinogens to stool, aiding in their expulsion from the body

3. Keeping you full longer, which may help prevent overeating and maintain a healthy weight

   
   

High-fibre foods to incorporate into your diet include:

• Wholegrain bread, pasta, and cereals

• Fruits such as pears, raspberries, and blackberries

• Vegetables like broccoli, kale and spinach

• Pulses such as beans and lentils

Calcium: Not Just for Strong Bones

While the ACS study didn't specifically highlight calcium, it did stress the importance of maintaining a healthy weight. Foods rich in calcium, especially low-fat dairy products, can be part of a balanced diet that helps with weight management.

The NHS recommends 700mg of calcium per day for adults. Good sources include:

• Dairy products like milk and yoghurt (about 200mg per 200ml of semi-skimmed milk)

• Fish with soft bones, such as sardines

• Green leafy vegetables like kale and okra

The Rainbow Foods: Fruits and Vegetables

The ACS study found that low consumption of fruits, vegetables, fibre, and dietary calcium contributed to a significant number of cancer cases. This backs up what we've said about the importance of these foods in potentially reducing cancer risk.

The NHS recommends at least 5 portions of a variety of fruit and vegetables every day as part of a healthy, balanced diet. One portion is about 80g, which could be:

• 1 apple, banana, or pear

• 3 heaped tablespoons of vegetables

• A dessert bowl of salad

  
  

Fruits and vegetables may help reduce cancer risk by:

• Lowering the risk of human papillomavirus (HPV), a leading cause of certain cancers

• Providing antioxidants that combat free radicals and reduce inflammation

• Supplying folate, which may help reduce HPV risk

The Red Flag: Processed Meats

The ACS study showed that diet-related factors, including eating red and processed meat, contributed to a substantial number of cancer cases. Specifically, about 13% of colorectal cancers could be attributed to processed meat consumption.

A study led by researchers at Imperial College London found that people eating around 76g of red and processed meat a day had a 20% higher chance of developing bowel cancer than those who ate about 21g a day.

To reduce risk, consider limiting intake of processed meats such as:

• Sausages

• Bacon

• Ham

• Ultra processed ready meals

Alcohol: A Notable Risk

The ACS study identified alcohol as the third largest contributor to cancer cases, associated with 5.4% of cancer cases. This emphasizes the importance of drinking less as part of a cancer-prevention strategy.

The NHS recommends:

• Not regularly drinking more than 14 units of alcohol a week

• If you do drink as much as 14 units a week, spread it over three or more days

• Try to have several alcohol-free days each week

Beyond Food: Other Ways to Lower Your Risk

While we've focused on food, the ACS study pointed out other important lifestyle factors that affect cancer risk:

1. Smoking was the biggest risk factor, linked to nearly 20% of all cancer cases and 30% of all cancer deaths.

2. Too much sun exposure was also a significant factor, with UV radiation exposure contributing to 4.6% of cancer cases.

3. Not getting enough physical activity played a role too, with physical inactivity contributing to 3.1% of cancer cases.

   
   

These findings show that preventing cancer isn't just about what we eat. It's also about not smoking, protecting our skin from the sun, and staying active.

In fact, for some specific cancers, the potential risk reduction through lifestyle changes is even more dramatic:

• More than 80% of melanoma skin cancers (92.2%) could be prevented, mainly through sun protection.

• 88.2% of lung cancers could be prevented, primarily by not smoking.

  
  

Dr. Ahmedin Jemal, another senior researcher at the ACS, stressed:

"These findings show we need to make it easier for everyone to access preventive health care and learn about ways to prevent cancer."

By making smart food choices and adopting a balanced, nutrient-rich diet, along with other healthy lifestyle habits, we can take significant steps towards lowering our cancer risk by up to 40%. Remember, it's never too late to start making positive changes for better health.