Healthy weight and cancer risk

Keep your weight within a healthy range and avoid weight gain as an adult to reduce your cancer risk.

Many people don’t realise that having overweight and obesity is a risk factor for 13 types of cancer, including cancer of the bowel, kidney, pancreas, oesophagus, endometrium, liver and breast (after menopause).

How does carrying excess body fat increase cancer risk?

Researchers are still investigating how carrying excess body fat causes cancer. However, there are several likely reasons, including:

• Too much body fat can cause insulin and other growth factor levels to rise, and this can make cancer cells grow.
• Fat cells release sex hormones that are linked with some cancers.
• Body fat stimulates inflammation that promotes cancer development.

How to check your health risk

The health risk associated with your body weight can be estimated using your waist measurement and body mass index (BMI).

Measure your waist

Having fat around your abdomen or waist, regardless of your body size, increases your risk of developing certain weight-related health conditions, including cancer.

1. Place a measuring tape firmly around your waist. For women – measure around the narrowest point of your waist. For men – measure around your navel
2. Make sure you breathe normally.
3. Use the table below to determine your health risk

Calculate your BMI

BMI is a simple way to find out if you are a healthy weight for your height. Work out your BMI by dividing your weight in kilograms (kg) by your height in metres squared.
Please note: BMI is not applicable for people under 18, pregnant women, people with higher levels of lean body tissue, and people from some ethnic backgrounds.

How to maintain a healthy weight

If you eat and drink more energy (kilojoules) than your body uses through metabolism, exercise and day-to-day activities, the spare energy is stored as fat and you gain weight.

The causes of weight gain are complex, and largely out of our control. This includes limited access to healthy foods and spaces that allow for physical activity, and marketing of unhealthy foods and drinks by the processed food industry.

Eating well and being physically active will reduce your cancer risk, regardless of your body weight. These behaviours may also help to avoid weight gain, maintain a healthy weight or lose weight to reduce cancer risk.

Here are a few tips to live a healthy life:

• Limit unhealthy foods and drinks high in kilojoules, added fat or sugars, e.g. sugary drinks, fast food or takeaway foods, potato chips, pies, cakes and sweets.
• Avoid large food portions or eating more often than your body needs.
• Be physically active.
• Cut down on sedentary time, e.g. watching television or using computers for long periods of time.
• Eat a balanced diet and do regular physical activity to avoid weight gain.
• Eat lots of wholegrains, vegetables, fruit and beans/legumes every day.

If you are living in a larger body, focus on making realistic and long-term changes to your current eating and activity patterns.

Avoid fad diets and extreme exercise plans. Being active and following a healthy eating and drinking plan most of the time is a good start. If you need more help, see your general practitioner (GP) or a dietitian.

Supporting healthy lifestyles: Government policies can influence the food environment, how and where food is priced, marketed and sold; and the physical environment, how easy it is to be active. Read more about supporting healthy lifestyles.