Choose mostly plant foods, limit red meat and avoid processed meat.
Making simple changes to your diet can help reduce your cancer risk.
The choices that affect your cancer risk
We all make choices every day about what we eat and drink, and how physically active we are.
And there is overwhelming evidence that the choices we make today can make a big difference to our cancer risk.
WCRF HK is committed to giving people the information they need so that when they make their daily choices, they are doing so based on the latest scientific evidence.
The lifestyle choices listed below show you the impact they can have on your risk of developing particular types of cancer later in life.
There is convincing evidence that alcoholic drinks are a cause of cancer of the mouth, pharynx and larynx; cancer of the oesophagus; and breast cancer. For colorectal cancer, the evidence is convincing for men and probable for women. Alcohol is also probably a cause of liver cancer.
The evidence that all types of alcoholic drinks are a cause of a number of cancers is now stronger than it was in the mid 1990s. For cancer prevention, WCRF HK recommends not to drink alcoholic drinks. However, evidence suggests that small amounts of alcohol may have a protective effect on the heart. But the benefits only outweigh the risks in those particularly at risk of heart disease, such as men aged over 40 and postmenopausal women.
WCRF HK recommends that if people choose to drink, they should limit themselves to one drink a day for a woman and two drinks a day for a man.
The evidence is convincing that being overweight is a cause of cancer of the oesophagus; pancreas; endometrium (womb); kidney; and post-menopausal breast cancer. It is also probably a cause of cancer of the gallbladder.
There is evidence that being overweight actually protects against pre-menopausal breast cancer, but the evidence is convincing that it is a cause of post-menopausal breast cancer, which is by far the most common type of breast cancer.
There is also a separate link between cancer and fat around the waist, and the evidence is convincing that it is a cause of colorectal cancer, and is also probably a cause of post-menopausal breast cancer and cancers of the pancreas and endometrium.
Because of the close link between cancer and body fatness, WCRF HK recommends that you should be as lean as possible within the healthy body weight range and that you should avoid putting on weight throughout adult life.
People who have put on weight should attempt to lose it, even if they are still within the healthy range. People who are already overweight should aim to lose weight.
Breastfeeding – There is convincing evidence that breastfeeding protects the mother against breast cancer, and it also probably protects the child against obesity later in life, which is in turn linked to a higher cancer risk.
This is why WCRF HK recommends that mothers breastfeed exclusively for the first six months, and then add liquids and foods.
Evidence shows that diets high in calcium probably protect against colorectal cancer, but they are probably a cause of prostate cancer.
Because of this conflicting evidence, WCRF HK has not made any recommendations on whether or not people should eat diets high in calcium, such as dairy products.
Evidence suggests that energy dense food, or food that has more than about 225-275 calories per 100g, probably contributes to weight gain and obesity.
Because of the close link between cancer risk and being overweight and obese, WCRF HK recommends that you should limit consumption of energy-dense foods, as well as sugary drinks.
The evidence also suggests that eating low energy-dense foods such as vegetables probably protects against weight gain and obesity.
Garlic probably protects against colorectal cancer.
Folate, a form of Vitamin B that occurs naturally in some fruits and vegetables, probably protects against cancer of the pancreas.
Evidence shows that eating a wide range of fruit probably protects against cancers of the mouth, pharynx and larynx; oesophagus; lung; and stomach.
This is why WCRF HK recommends people eat at least five portions of a wide variety of fruits and vegetables every day.
High-fibre diet – The evidence shows that foods containing dietary fibre protect against colorectal cancer.
This is one of the reasons why people should be eating a diet that mostly consists of plant foods.
The evidence shows that lycopene, which is found in tomatoes and other red fruits, probably protects against prostate cancer.
The evidence is convincing that physical activity protects against colorectal cancer, while it also probably protects against post-menopausal breast cancer and cancer of the endometrium.
The evidence is also convincing that physical activity protects against weight gain and obesity, which are both closely linked to cancer.
Because of this, WCRF HK recommends people should be physically active for at least half an hour a day, and that as physical fitness improves they should aim for an hour of daily moderate physical activity, such as brisk walking or gardening, or half an hour of vigorous physical activity, such as running or playing football.
The evidence is convincing that processed meat is a cause of colorectal cancer.
Processed meat refers to any meat that is preserved by salting, curing, smoking, or adding chemical preservatives. This means meat such as ham, bacon and hot dogs and some sausages.
The data shows that eating even a small amount of processed meat is linked to increased risk of colorectal cancer. This is why WCRF HK recommends people avoid eating processed meat.
The evidence is convincing that red meat, such as beef, lamb and pork, is a cause of colorectal cancer.
This is why WCRF HK recommends that people eat no more than 500g of it per week.
Salt and salty food
The evidence suggests that salt and salty foods are probably a cause of stomach cancer.
For this reason, WCRF HK recommends that people avoid salty foods and have less than 6g of salt a day.
The evidence shows that selenium, which is found in dietary supplements, probably protects against prostate cancer.
However, WCRF HK recommends that people generally do not have supplements to protect against cancer and instead get their all their nutrients from their diet.
Selenium is also found in foods such as brazil nuts.
The evidence shows that sugary drinks probably cause weight gain and obesity. Because of this, WCRF HK recommends that people should avoid sugary drinks.
While this includes drinks with added sugar such as fizzy drinks, we should also limit the amount of fruit juice we drink to one glass a day.
Water is the ideal drink, but things like unsweetened tea and coffee and diet soft drinks are also alternatives.
The Expert Report found strong evidence that high-dose supplements of some nutrients can affect the risk of some cancers.
But in general, the best source of nourishment is food and drinks, not dietary supplements. There are some situations when supplements are recommended – your healthcare provider can advise you when it is necessary.
The evidence shows that eating plenty of a variety of non-starchy vegetables probably protects against cancer of the mouth, pharynx and larynx; oesophagus; and stomach. Non-starchy vegetables do not include peas, potatoes, squashes, and corn.
This is why WCRF HK recommends eating at least five portions of a variety of vegetables and fruits every day.
No list of this type would be complete without emphasising that you should not use tobacco.