Body weight

Almost 2 in 3 Australians adults are either overweight or obese. Excess body fat is associated with a number of chronic diseases including diabetes and heart disease. Research also shows that being overweight or obese increases the risk of a number of cancers.

There is convincing evidence that overweight and obesity increases risk of:

• Oesophageal (food pipe) cancer
• Pancreatic cancer
• Bowel cancer
• Breast cancer (in women who have had their menopause)
• Endometrial cancer (lining of the womb or uterus)
• Kidney cancer

There is probable evidence that overweight and obesity increases risk of:

• Gall bladder cancer

Poor food and drink choices and not enough physical activity often lead to weight gain. Good nutrition and regular physical activity help you to maintain a healthy weight, and reduce your risk of cancer.

How do I know if I am overweight or obese?

There are two ways you can find out if you are overweight or obese. One is the body mass index (BMI), the other is waist circumference measurements. Neither method is perfect but when used together they are useful in determining how healthy your weight is.

Body Mass Index (BMI)

BMI compares your weight to your height.  BMI is calculated by dividing your weight in kilograms by your height in metres squared.  If you enter your height and weight below, you can calculate your BMI.

Source: World Health Organization, 2004.

Note: The BMI may not be accurate for people with greater muscle mass (such as athletes) or in older people and others who have lost muscle mass.

If your BMI is between 18.5 and 25, you are in a healthy weight range.  You should continue to maintain your weight.

If your BMI is above 25, you are above the healthy weight range.  This puts you at a higher risk of developing cancer.  Try to look for ways to improve your diet and increase your activity levels.  Remember, every small change you make counts!  Refer to some of the healthy eating and exercise tips on our website to help you work towards a healthy weight range to reduce your risk of cancer.

If your BMI is below 18.5, you are below the healthy weight range.  Being underweight puts you at risk of poor health.

If you require professional advice on managing your weight, consult your doctor or an accredited practising dietitian to help you achieve a healthier weight.

Waist circumference

Waist circumference indicates how much fat you have around the middle of your body or abdomen (stomach). Having weight around your middle is a risk factor for many chronic diseases, including some cancers, type 2 diabetes and cardiovascular disease. It is more of a health risk than the weight on your hips or thighs.

Use a measuring tape to measure your waist circumference around the narrowest point of your body (see diagram). Measure at the end of a normal breath, and ensure that the tape is firm; not too tight or too loose.

You may be at a higher risk of developing cancer if your waist circumference is above the healthy range.

Women

• 80 cm or more increases risk
• 88 cm or more substantially increases risk

Men

• 94 cm or more increases risk
• 102 cm or more substantially increases risk

Source: World Health Organization, 2000. 

So what should I do?

Balance energy in and energy out

You obtain energy from the food and drinks (including alcohol) you consume and burn energy via physical activity. This includes physical activity done as part of your daily routine - such as taking the stairs instead of the lift - and planned activity such as going for a walk, cycling or playing sport.

If you already have a healthy body weight, you can maintain it by balancing your energy intake and output. 

If the amount of energy you take in from food and drinks is more than the amount you use in daily physical activity, your body stores the excess energy as fat, and over time you will gain weight.

If the energy you take in from food and drinks is less than the energy you use in daily physical activity, over time you will lose weight.

How much brisk walking do I need to do to burn off a:

• 55 g bar of milk chocolate (1185 kJ) - 56 minutes
• 375 mL can of soft drink (655kJ) - 31 minutes
• Packet of takeaway hot chips (1838kJ) - 1 hour and 28 minutes

Eat well

Eating well provides you with valuable nutrients and energy, and will help you to reach and maintain a healthy weight. Understanding energy density and portion control will help you to eat well.

Avoid energy dense food and drink

All foods and drinks, except water, contain energy measured in kilojoules (kJ) or calories. The energy density of a food is the amount of kilojoules or calories per gram of food.

The higher the water content of a food, the lower its energy density. Fat is the most energy dense nutrient and provides 38 kJ of energy per gram while carbohydrate and protein provide around 17 kJ of energy per gram.

If you base your meals and snacks mainly on low energy dense foods, some medium energy-dense foods and limit high energy dense foods, this will help you to reach and maintain a healthy weight.

Here are some tips to reduce the energy density in your diet:

• Start your meal with a low energy density entrée (starter) such as a broth-based soup or a salad (without oily dressing)
• Bulk up your meals with low energy-dense foods:
  • Add vegetables and legumes to pasta sauce
  • Add lentils or pearl barley to soups and stews
  • Make vegetables the main meal and meat a side dish
• Prepare foods using healthy cooking methods:
  • Choose to grill, steam or bake foods and don't use fat or oil
  • Limit foods that are fried or baked in fat
• Swap high energy-dense foods for less energy dense options:
  • Choose reduced-fat dairy products instead of full fat versions
  • Choose tomato-based pasta sauces instead of creamy or cheese-based ones
  • Choose reduced-fat and low sugar products such as reduced-fat mayonnaise and fruit canned in natural juice instead of syrup
  • Snack on fruit and vegetables instead of confectionary (sweets/lollies) and crisps
  • For dessert, choose fruit salad and reduced-fat yoghurt instead of ice cream or cream

• Eat smaller portions of high energy-dense foods
  • Handle your chocolate craving by having a fun size chocolate bar instead of a regular or king size bar
  • Eat small servings of desserts and pastries, for example half a muffin, one small scoop of ice cream or share dessert with a friend

Limit high energy drinks

Due to their water content, drinks are less energy dense than foods. However sugary drinks provide lots of kilojoules and little or no nutrients. Water is the best choice. Drinks such as fruit juice, soft drinks and cordials should ideally be avoided, or at least consumed infrequently and in small amounts.

Eat more fruit and vegetables

Eating more fruit and vegetables is an easy and nutritious way to reduce the energy density of your diet. You should aim for 2 serves of fruit and 5 serves of vegetables every day. Try to include at least one fruit or vegetable in all your meals and snacks.

Here are some tips on how to eat more fruit & vegetables:

• Add bananas, oranges, sultanas, or grated carrots, zucchini or apple, to muffins
• Add banana or berries to porridge and breakfast cereals
• Make a vegie omelette for breakfast or brunchon the weekend
• Top toast with banana or avocado
• Enjoy a smoothie made from fresh or frozen fruit and reduced-fat yoghurt or milk
• Eat fruit-based desserts such as chopped fresh fruit, stewed fruit or baked apples
• Make vegie pizzas using leftover roasted or grilled vegies
• Increase the amount of vegies in your stir fries
• Bulk up soups, stews and pasta with vegies and legumes such as lentils
• Keep a selection of reduced salt or no added salt canned and frozen vegetables in your cupboard and freezer so you always have a substitute when fresh ones aren't available

Avoid alcohol

Just like any food or drink you consume (except water), alcoholic drinks contain energy. In fact, alcohol contains few nutrients but is very energy dense.

In Australia, one ‘standard drink' contains 10 grams of alcohol, which gives you 290 kJ of energy. If the alcohol is mixed with other sugary drinks (mixers), it contains even more energy. For example, a can of bourbon and coke provides about 690 kJ of energy and would take about 35 minutes of brisk walking to burn off.

Another downside of alcohol is that it is easy to consume much more than a standard drink!

The drinks served in restaurants, pubs and at home are often much larger than one standard drink. For example, a small glass of wine in a restaurant is about 150 mL, which is one and a half standard drinks.

If you are trying to achieve or maintain a healthy weight, it is best to avoid drinking alcohol. Alcohol also increases your chances of developing cancer in specific parts of the body, including the mouth, throat (pharynx and larynx), oesophagus (food pipe), bowel, breast and liver.

There is no safe alcohol level with regards to cancer. If you do choose to drink alcohol, the recommendations are that men and women should have no more than two standard drinks per day, and have multiple alcohol-free days a week.

To compare:

• 1 gram of alcohol = 29 kJ of energy; whereas
• 1 gram of protein or carbohydrate = 17 kJ of energy

Don't eat too much

Reaching and maintaining a healthy weight is not only about what you eat, but also about how much you eat. Portion control is very important in helping you to achieve your healthy weight goals.
For the best nutrition health professionals recommend adults should consume the following number of serves from each of the five main food groups every day:

Energy dense foods that are high in fat and sugar, such as desserts, biscuits, cakes, sugary drinks and chips, are ‘extra' foods that should not be part of your everyday food intake, especially if you are trying to lose weight.
Remember that ‘extra' foods do not fill you up as much as healthy, low energy dense foods, so it is easy to over eat ‘extra' foods.

Tips: Controlling your food portions

• Use smaller plates
• Store foods in individual portions rather than in bulk containers
• Don't eat from the bag or packet - put a small amount of snack food into a bowl and put the packet away
• Order entrée (starter) sizes or small meals at restaurants
• Eat slowly and enjoy the food. It takes 10 to 20 minutes for your stomach to signal to your brain that you are full
• Resist up-sizing or purchasing ‘value meals' at fast food restaurants
• If you eat food from the ‘extras group', share it with a friend

Be active

Being active has an important role in helping you achieve and maintain a healthy weight. It also helps you sleep better and feel healthier! 

• Energy In = Energy Out

For weight maintenance, aim for at least 30 minutes of moderate-intensity physical activity on most, preferably all, days.

For weight loss and cancer prevention the more physically active you are the better. As fitness improves aim for at least 60 minutes of moderate intensity activity or 30 minutes of vigorous-intensity activity every day.

How do I know the intensity of the activity I am doing?

Use the Talk Test. While performing light-intensity activity (such as slow walking, light housework or gardening) you should be able to sing. During moderate-intensity activity (such as brisk walking, flat cycling) you should be able to carry on a conversation comfortably. During vigorous intensity activity (such as running, cycling uphill) you should be too out of breath to carry on a conversation.

It's easy to include some physical activity every day.

Tips: Increasing your physical activity

• Organise a weekly group activity with your friends such as a netball game or a long walk.
• Exercising with friends helps with motivation and commitment
• Use physical activity as transport to get from one destination to another (e.g. walk, cycle)
• Park your car further away from your destination and walk some of the way
• Do gardening and housework
• Do stretching exercises while watching television
• Take a brisk walk during your lunch break
• Join a fitness centre near your work, and work out before or after work while you avoid rush hour traffic
• Walk your dog
• Use the stairs instead of the lift
• If you have children, plan active family time such as going to the beach for a swim, or bushwalking
• Get off the bus or train a few stops earlier and walk
• Cycle to work
• Go for a walk after dinner or before breakfast - or both!
• Join your local sports group

Diets don't work

For healthy weight loss ‘dieting' is not recommended. Rather, we recommend gradual and realistic changes to your food and exercise routine that will last a lifetime.

It's about balancing your food and exercise and enjoying the positive changes you are making towards a healthier lifestyle. Start by setting 3 goals. Once you have achieved these goals include 3 more goals and so on. Making small changes is a realistic way to a healthier lifestyle that you can maintain forever.

Goals:

1. I will include extra vegetables with lunch and dinner
2. I will walk for 30 minutes every day
3. I will drink water instead of juice and soft drink

Where to go for more information

Many organisations are working to help people achieve and maintain a healthy body weight in order to reduce the risk of a number of chronic diseases. To find out more about some of the different programs available in Western Australia and throughout the rest of the country choose from the links below:

Western Australian Campaigns

• LiveLighter is a program encouraging Western Australian adults to lead healthier lives - to make changes to what they eat and drink, and to be more active. We want to help people understand why they need to take action and what simple changes they can make in order to ‘LiveLighter'. It is funded by the WA Department of Health and delivered by Cancer Council WA.

National Campaigns

• Swap It, Don't Stop It! Campaign followed on from the Measure Up Campaign and highlighted the link between increased waist size and the risk of chronic disease. Eric, an animated balloon character, is the face of the new campaign. Over the years Eric's belly has ballooned but he is now making small changes to his lifestyle to improve his health. He is encouraging you to join him too.

National organisations, websites and documents

• Diabetes Australia is a national federated body comprised of state and territory organisations supporting people with diabetes and those professional and research bodies, particularly concerned with the treatment and prevention of diabetes. Its purpose is to help all people affected by diabetes and those at risk and to contribute to the search for a cure.

• Dietitians Association of Australia (DAA) is the national Association of the profession, with branches in each State and Territory. As well as supporting its members, DAA advocates for better food and improved health in order to reduce chronic disease in the Australian population.

• Healthy Weight Website is an initiative of the Australian Government, Department of Health and Ageing. It provides information and advice on healthy body weight, healthy eating and physical activity.

• National Heart Foundation aims to save lives and improve health through funding cardiovascular research, providing guidelines for health professionals, informing the public and assisting people with cardiovascular disease.

• Nutrition Australia is an independent, member organisation that aims to promote the health and well-being of all Australians.

• The Parents Jury is an online network of parents, grandparents and guardians, who are interested in improving the food and physical activity environments of Australian children. It provides a forum for parents to voice their views and to collectively advocate for the improvement of children's food and physical activity environments.

To find out more about how overweight and obesity can increase your cancer risk see the position statement on Overweight, obesity and cancer prevention.