Researchers believe that the foods people eat over their lifetime can increase or decrease their risk of developing some types of cancer. About one-third of all cancers are related to what we eat and drink, our body weight and the amount of physical activity we do.
The exact relationship between diet and cancer needs more study, but there is scientific evidence to link some food groups and individual foods to cancer risk.
Meat
Diets high in red meat or processed meat increase the risk of colorectal cancer. Studies have linked cured or smoked meat and eating large amounts of foods preserved by salting and pickling to an increased risk of stomach cancer.
Fibre
Vegetables, fruit, whole grain foods and legumes are high in fibre. Fibre helps keep the digestive system healthy and the bowels regular. Eating foods that contain fibre decreases the risk of colorectal cancer.
Vegetables and fruit
Vegetables and fruit play a key role in a healthy diet. They are excellent sources of vitamins and minerals and are high in fibre and low in fat and calories. Vegetables and fruit may help protect against certain types of cancer.
Salt
Research shows that eating too much salt and salty food may increase the risk of stomach cancer.
Sugar
Eating lots of foods that have sugar added can cause weight gain. Being overweight or obese increases the risk of cancer.
Dietary fat
A diet high in fat increases the likelihood of gaining weight. Being overweight or obese increases the risk of cancer.
Vegetarian diets
A well-balanced vegetarian diet tends to be healthy if it is low in saturated fat, high in fibre and includes a variety of vegetables and fruit. But diets that include lean white meats and fish, and red meats in small amounts can also be healthy.
Food issues
Some methods of cooking, preparing and storing food have also been associated with cancer. Some cancer-causing chemicals are created when meats are cooked at high temperatures and increase the risk of some types of cancer such as colorectal cancer. A harmful substance, such as aflatoxin, can be found in mouldy foods and is linked to an increased risk of liver cancer.
Reducing your risk
About one-third of all cancers can be prevented by eating well, being active and maintaining a healthy body weight. You can lower your risk of cancer by making simple changes to the way you eat and becoming more active.
- Eat a variety of foods from Canada’s Food Guide. Eating a healthy diet – lots of vegetables and fruit, lots of fibre and little fat and sugar – will help you get all the nutrients you need and will help you keep a healthy body weight.
- Eat regular meals. Skipping a meal – especially breakfast – can lead to overeating throughout the day. And when you’re very hungry, it’s hard to make healthy choices.
- Re-think your plate. Fill half your plate with vegetables, a quarter with grain products and a quarter with meat or alternatives.
- Cut back on portion size. (Portions in North America have grown steadily bigger over the last few decades.) Make sure that you’re not eating more than your body needs. If your portions are a reasonable size, it will be easier for you to eat what you want but still stay healthy.
- Use smaller dishes. Believe it or not, using a smaller plate gives your brain the impression that you’re eating your “normal” amount of food.
- Serve everything you eat in a dish – especially snacks. You’ll be much less likely to overeat if you’re not eating out of the box or bag.
- Make changes gradually. For example, if you try to switch from homogenized milk to skim, you may give up because you don’t like the taste. Try switching first to 2%, then 1%, then skim, and you may be more successful.
- Try to plan your meals for the whole week. Last-minute choices are often unhealthy ones.
- Don’t go grocery shopping on an empty stomach. You’ll make better choices if you’re not hungry.
- Read nutrition labels. “Low-fat” and “fat-free” doesn’t always mean low in calories.
- Don’t eat while watching TV.
- Choose wisely when you eat in restaurants – skip the fries and sugary drinks, and ask for dressings on the side.
- Slow down and enjoy every bite. It actually takes 20 minutes for your brain to get the message that your stomach is full.
- Try to limit how often you eat processed food – they often contain hidden fat, calories, sugar and salt.
- Balance the food you eat with regular physical activity to help achieve and maintain a healthy body weight.
- Choose water instead of pop and sugary drinks. Drinking water is important for your body to work properly.