Cancer and diet: The link

MANY factors can contribute to the development of chronic diseases, including certain types of cancer.

Certain dietary patterns and food choices do have associations with an increased risk of cancer.

Researchers have predicted that cancer will become the leading cause of death in every country in the world by the end of this century, making prevention a top priority in the healthcare eld.

In the early 1960s, researchers discovered that cancer rates varied between countries and identi-fied that specific dietary patterns have correlations with certain types of cancer.

They also discovered that cancer rates in people from countries with a low cancer risk who migrated to countries with higher cancer risk matched or exceeded the cancer rates in the country they migrated to. This suggests that diet and lifestyle strongly impacted cancer development.

Since then, researchers have narrowed down the specific foods and dietary patterns that may increase the risk of certain cancers.

Research into diet and cancer risk is ongoing. Researchers still have much to learn about how and why food choices a ect cancer risk.

Alcohol consumption

Having more than two drinks each day for many years may increase the chance of developing cancers of the mouth, throat, esophagus, larynx, liver, and breast. The risk increases with the amount of alcohol that a person drinks. For most of these cancers, the risk is higher for a drinker who also uses tobacco.

It is advisable to drink alcohol in moderation. This means no more than one drink per day for women and no more than two drinks per day for men. Unfortunately, it is not advisable to save all your drinks during the week and drink them all on Friday night!

Red wine contains a compound called resveratrol, found in red and black grape skins, which is a very potent antioxidant that can help protect the body from free radical damage. If you like to drink alcohol, your tipple of choice should therefore be a glass of good red wine.

Red and processed meats

Scientists know there is a strong link between processed meat intake and certain types of cancer.

In 2015 the International Agency for Research on Cancer, part of the World Health Organisation, classified processed meat as carcinogenic and unprocessed red meat as “probably” carcinogenic.

A 2018 review found that increasing intake of processed meat up to about 60g per day and red meat up to 150g per day increased colorectal cancer risk by about 20%.

Diets high in processed and red meat also have associations with an increased risk of other cancers, including stomach cancer and breast cancer.

Compounds created during high-temperature cooking and smoking processes can cause cellular damage, which can initiate the development of cancerous cells. The heme iron found in red and processed meats may also have a toxic e ect on cells.

Ultra-processed foods

Ultra-processed foods often contain ingredients that result from industrial processing, such as protein isolates, hydrogenated oils, high-fructose corn syrup, avor enhancers, artifcial sweeteners, and thickeners.

Examples of ultra-processed foods and beverages include ultra-processed sweet and savory snack foods, soda and energy drinks, breakfast cereals, reconstituted meat products, frozen pizzas, candy, and more.

Ultra-processed foods are rich in saturated fat, added sugar, and salt, but low in protective nutrients, such as bre, vitamins, and minerals. Ultra-processed foods also contain potentially carcinogenic compounds formed during processing, such as heterocyclic amines and polycyclic aromatic hydrocarbons.

Certain food additives and contamination by chemicals from food packaging may also contribute to the increased cancer risk associated with the consumption of ultra-processed food.

In addition to cancer, ultra-processed food intake has links to many other chronic conditions, including type Two diabetes and heart disease, and an increased risk of death from all causes.

High-salt diets

A diet high in added salt may increase the risk of certain cancers, particularly stomach cancer.

Scientists have suggested that high salt intake may increase the risk of infection caused by Helicobacter pylori bacteria. H pylori infections signi - cantly increase the risk of stomach cancer.

Diets high in added salt have associations with an increased risk of certain cancers, including stomach cancer and esophageal cancer.

Scalding beverages

Drinking scalding hot beverages may increase cancer risk. The IARC has classified beverages with a temperature over 65°C as “probably” carcinogenic to humans.

Lack of exercise and obesity

A lack of physical exercise is strongly linked to obesity. Obesity increases the risk of developing breast, endometrial, colon, kidney, oesophagus and gall bladder cancer.

• This article is part of a series supported by PSMAS aimed at raising awareness on cancer.