Type “Can food prevent cancer?” and you’ll get many recommendations for which food to avoid preventing cancer. Don’t overcook the food, cut sugar, go vegan, eat broccoli. But how often do these claims hold? Can food cause cancer, or can food prevent cancer?

Well, nutrition plays a significant role in our day-to-day life. Many factors can contribute to the development of chronic diseases such as cancer. The relationship between diet and cancer risk is complex. On the other hand, specific dietary patterns and food choices have been linked to an increased risk of cancer.

What does the research say?

Researchers in the 1960s found that cancer rates differed between countries and were linked to particular dietary patterns. Cancer rates in people who moved from low-risk countries to high-risk countries were found to be equal to or higher than the rates in the new country. This implies that diet and lifestyle have a significant impact on cancer development.

Since then, researchers have narrowed down the specific foods and dietary patterns that may increase the risk of certain cancers. This article will mainly discuss food, but we must remember that drinking alcohol is also a recognised dietary risk. 

But how does a specific food, or type of food, affect our cancer risk? Here is the evidence–or lack of evidence– behind some of the most popular cancer-related diet claims.

The Claim: Sugar Promotes Tumour Growth

Sugar molecules, commonly known as carbohydrates, are the primary energy source for all cells in our body, including malignant cells. However, there are other sources of energy for our cells. Other nutrients, such as proteins and lipids, can be used by cells to develop.

Scientists are looking into whether specific diets can help inhibit tumour growth. Studies on rodents and humans indicate that the ketogenic diet, which is low in carbohydrates and high in fat, may slow down the growth of certain tumours, like the ones in the rectum when combined with standard cancer treatments such as radiation and chemotherapy. 

According to Neil Iyengar, MD, an oncologist at Memorial Sloan Kettering Cancer Center in New York City, ketogenic diets lower insulin levels. Research in mice shows that high insulin levels can weaken the ability of specific therapies to slow tumour growth.

The Verdict: Cutting sugar won’t stop cancer from spreading. Preliminary research suggests that a low-carb diet may improve the effectiveness of specific cancer treatments.

The Claim: Consuming overcooked or charred food causes cancer.

Some foods, notably carbs like bread or potatoes, emit acrylamide when cooked at high temperatures.

Scientists discovered that high quantities of acrylamide, commonly found in food, can induce tumours to grow in animals. On the other hand, human studies have shown minimal evidence that acrylamide in meals increases the risk of cancer. 

Different cooking methods for meat, like pan frying, grilling, or smoking, can create extra compounds called heterocyclic amines and polycyclic aromatic hydrocarbons. 

Rodents exposed to high quantities of these compounds, like acrylamide, develop tumours in multiple organs. However, the data on people could be more precise. 

While some studies suggest that consuming chemicals from cooked meats may raise the risk of some malignancies, such as colorectal or pancreatic cancer, others have found no link.

The Verdict: There is insufficient evidence to conclude that eating overcooked or burnt food causes cancer in people.

The Claim: Consuming Processed Foods Leads to Cancer

The evidence associating processed meats like salami, beef jerky, and cold cuts to the risk of some cancers, specifically colon cancer, is compelling.

In 2015, the World Health Organization’s International Agency for Research on Cancer (IARC) classified processed meats as a Group 1 carcinogen reserved for cancer-causing chemicals. 

After reviewing hundreds of studies with 22 experts from 10 nations, the agency concluded that consuming processed meat is linked to a higher risk of colorectal cancer in humans. 

Some long-term studies suggest that other “ultra-processed” foods, such as soda, canned soups, and instant noodles, may raise the chance of acquiring cancer. These meals can have harmful substances like acrylamide, nitrates, heterocyclic amines, and polycyclic aromatic hydrocarbons. They also tend to be high in added sugar, salt, and saturated fat.

The Verdict: There is a clear correlation between processed meat and cancer risk. Although there is evidence that red meat and ultra-processed foods may increase cancer risk, the data is not as robust.

Is there any “anti-cancer” diet?

There is no single diet that can guarantee that you will not develop cancer. A healthy, balanced diet, on the other hand, can minimise the risk.

We often hear that eating a healthy and balanced diet benefits our health, but what does this mean?

To have a healthy diet, eat lots of fruits, vegetables, and whole grains like brown pasta and wholegrain bread. Opting for lean protein sources such as fresh chicken, fish, or legumes such as lentils and beans is crucial.

Limit your processed and red meats, such as bacon, sausages, and chicken nuggets. Avoiding high-calorie foods like fast food and sugary drinks such as sodas, energy drinks, and alcohol is also suggested.