The size of your belly can be an accurate barometer of your future health risks. Stephanie Osfield tells how you can make a difference.
We may play down our widening waistlines by calling them muffin tops, love handles and spare tyres, yet Australian bellies are getting bigger and bigger.
More than 66 per cent of women and 60 per cent of men sport a belly size big enough to be considered a health hazard.
Carrying excess fat around your middle is now known to be more dangerous than fat around your hips and thighs.
“In excess, the fat we can see on our tummy is often a sign of fat hiding in the abdomen,” says Tim Crowe, Associate Professor of Nutrition at Deakin University.
This more dangerous visceral fat accumulates deeper in the belly where it wraps around vital organs, like your kidneys and heart. Unseen and undetected, it can wreak hormonal havoc.
“Visceral fat is metabolically active,” he explains.
“Fat cells in the abdomen are like little factories that pump hormones into the body - in women who are overweight for example, this may lead to excess oestrogen, which can compromise fertility and has been linked to some oestrogen-sensitive breast cancers,” he says.
Visceral belly fat also produces inflammatory chemicals.
“These are linked to conditions like diabetes, heart disease, asthma and arthritis,” says Professor Joseph Proietto of the Department of Endocrinology at the University of Melbourne.
“In the heart, they may lead to the build-up of plaques in the arteries which can increase the risk of heart attack.”
A belly fat time bomb
“Visceral fat continuously releases free fatty acids into the bloodstream,” Prof Proietto warns.
“These go straight to the liver where they increase the production of other fats like ‘bad’ LDL cholesterol and triglycerides and also lead the body to produce more glucose, which may then get stored as more fat.”
This excess fat (stored around the body) can accumulate in the neck and contribute to sleep apnoea, in the heart where it can narrow the arteries, and in the muscles, where it can prevent them from using the glucose that is stored there.
In addition, visceral fat releases ‘bad’ chemicals that can stop glucose from getting to where it needs to go to be used for energy. As a result, glucose levels in your bloodstream rise. Your body then tries to get rid of the excess glucose by pumping out more insulin - the hormone that helps taxi glucose into cells.
“To stop this excess insulin your body shuts down the insulin receptors on the outside of your cells. This is called insulin resistance, an unhealthy state that can cause type 2 diabetes,” Prof Proietto says.
There IS good news!
But there is good news. If you decide to shed weight, some of this visceral fat is among the first to go.
When you cut back on kilojoules, your body usually burns visceral fat first. Add exercise to the mix and this also encourages the loss of visceral fat - even if you’re not losing a great deal of weight.
So, if you’ve gone up a notch or two on your belt, there are simple changes that can help shave centimetres from your waist and add years to your life, says Ass Prof Crowe.
Burn, belly burn!
How to get started
Exercise increases the body’s lean muscle and muscle tissue burns more kilojoules than fat tissue, even at rest. So, aim for at least half an hour of exercise every day.
“Walking around three to four km daily can help you maintain a healthy weight and reduce belly fat - but make sure to stride, not stroll, so that you feel a bit breathless if you try to talk,” says Dr Nathan Johnson, exercise physiologist and Researcher at the Boden Institute of Obesity, Nutrition, Exercise and Eating disorders.
For weight loss Johnson recommends, “activities that use large muscles such as cycling, swimming, dancing or aerobics.”
Too busy or tired for a full half hour? Try short 5-10 minute exercise bursts, with 8-20 seconds of activity and 12-20 of recovery, known as High Intensity Interval Training (HIIT).
“Studies show some people lose belly weight faster and in less workout time by engaging in activities that cause rapid breathlessness like jumping, skipping or riding a stationary bike,” says Kate Pumpa, Assistant Professor of Exercise Physiology at the University of Canberra.
“HIIT helps you expend a large amount of kilojoules in a short space of time and quickly uses up your glycogen stores so that your body burns fat for fuel.” Check with your GP before you start any new exercise routine.
The biggest causes of belly fat
Whether it’s beer guts or muffin tops, do our male or female hormones really dictate our midriff measurement? “They do to some extent,” says Ass Prof Crowe. “Men are more prone to gain weight in their belly due to testosterone.”
Eating too much
While high-fat foods like creamy cakes, cheesy pizzas and burgers don’t help, eating too much in general is just as responsible.
It’s not only high in kilojoules but when you drink, your liver is too busy burning off the alcohol to burn off the fat. Alcohol can also affect the hormones that regulate satiety, causing you to overeat. Result: waist gain.
Lack of daily activity
For men, it can be a rude awakening to discover that after being able to seemingly eat anything during their teens and twenties, once they hit their thirties, have a family and a more demanding career, they gain a new gut companion. It’s a lack of activity, whether organised sport or general racing around, that means those big hearty meals that were once burned up, are now surplus to requirements, and end up as extra weight around the waist.
It’s a time when many women develop an unwanted belly. “Lower oestrogen levels after menopause can lead women to store weight more like men around their belly, gaining visceral fat and increasing the risk of heart disease,” Ass Prof Crowe adds. Once again, any weight gain is exacerbated by lack of activity and too many high-kilojoule foods.
The sleep connection
Many studies show people who sleep less than five hours a night weigh more, particularly in middle age. At the University of Chicago, it took only four nights of slashing sleep to 4.5 hours for the fat cells in otherwise young, healthy and lean men and women to become 30 per cent less responsive to insulin. This indicates the start of insulin resistance (where cells no longer effectively utilise glucose and insulin for energy) which can lead to pre-diabetes, the precursor to type 2 diabetes.
“Stress can also upset the appetite hormones that cause hunger, leading us to eat more,” says Prof Proietto.
The guts of the problem
Aside from heart disease, diabetes and cancer, abdominal weight gain is linked to many other health issues:
Belly fat, particularly from middle age onwards ramps up risk of dementia later in life, shows research by Boston University School of Medicine.
Harvard research has shown men carrying deep visceral fat suffer decreased bone density and strength.
Women and men aged between 20 and 55 suffer more migraines if they have bigger waistlines, shows research from Drexel University in the US.
Poor sleep quality
Losing weight, particularly belly fat, improves sleep and reduces daytime tiredness according to a Johns Hopkins study.
Women carrying more belly fat before menopause are at greater risk of some types of breast cancer, shows research led by Brigham and Women’s Hospital.
Research by the University of Science and Technology in Norway found adults with bigger bellies were more likely to develop asthma, even if they weren’t overweight.
Are you at risk?
What’s the tipping point from a healthy belly to hazardous one? It’s not quite as simple as doing a pinch test.
“Slim people who run marathons regularly can still grab a little bit of abdominal fat, and it is not this fat but the deeper visceral fat which is most dangerous,” says Prof Proietto. He points out that cholesterol, blood sugars and blood pressure should be regularly checked and always considered along with your waist circumference.
Your waist circumference
According to the Department of Health and Ageing, waist measurement is a more reasonable guide to your risk of health problems than your weight or BMI.
“If you increase exercise, your weight on the scales might go up due to muscle gain, so measuring the loss of centimeters from your waist is often a better indication of weight loss and health benefits,” says Dr Pumpa.
To measure your waistline
Measure directly against your skin.
Breathe out normally.
Make sure tape is snug, without compressing your skin.
Measure halfway between your lowest rib and the top of your hipbone, roughly in line with your belly button.
Don’t have a tape measure? Download one from the government’s Measure Up website at measureup.gov.au.
Generally, the following waist measurements are a guide to your potential risk of chronic disease, like type 2 diabetes or heart disease.
94cm or less
80cm or less
More than 102cm
More than 88cm
How to whittle your waist
To help you lose weight, especially around your middle, here are your go-to foods – and the ones to limit.
Foods to eat more of
Make these a daily part of lunch as well as dinner. They lend satisfying bulk to sandwiches and make tasty salads, too. Look for capsicum, leafy greens (lettuce, spinach, bok choy), cauliflower, tomatoes and mushrooms.
Chickpeas, lentils, kidney beans
These are high in filling fibre. They are perfect to add to salads, pastas, taco mixes and chilli con carne.
Try trimmed steak, chicken breast and lean mince. A healthy portion is the size of your palm. Make sure your dinner has twice the serving size of vegies as meat.
Opt for skim milk on morning cereal, eat low-fat yoghurt as a morning snack and try the tasty varieties of reduced-fat cheese.
Have a bowl of muesli or porridge for breakfast, look for grainy bread or crispbreads for your lunch and choose brown rice for stir-fries and even sushi. These are all filling options.
Keep fresh fruit, a handful of nuts, or hommous with vegie sticks on hand for nourishing snack choices. You’ll be less likely to give in when temptation arises.
Small amounts of good fats
Use olive oil-based salad dressings, try avocado instead of butter on your sandwich and toast and when cooking, use a spray oil, like canola or olive.
Foods to eat less of
Sugary soft drinks and cordial add loads of empty kilojoules, so keep them to once-a-week treats. Even juice needs to be limited to a 125ml glass, or you end up with more far more kilojoules than health benefits.
Large full-fat coffees
Downsize and opt for skim milk and watch out for any added syrups, too.
Salami, steak with fat marbled through it, fatty minces, chicken thighs, or BBQ chicken with the skin on all add lots of saturated fat.
Chocolate bars, potato chips, big muffins and cake are fine once in a while. But, eating them more than once a week can quickly sabotage your aim to shed belly fat. Keep these to occasional treats.
White bread, rice cakes and processed cereals all get digested more quickly, so won’t keep you as full as wholegrain choices. In fact, a 2008 review found "there is strong evidence that a diet high in wholegrains is associated with a lower body mass index, smaller waist circumference, and reduced-risk of being overweight." So ditch the refined stuff and go for wholegrain!
Lots of takeaway or deep-fried food
Fish and chips, pizza, burgers and hot chips are all high in kilojoules, saturated fat and salt. If you’re trying to lose weight, these foods are best kept to once a fortnight.
Myth: Weight training burns more belly fat
“Our research looked at this directly and found that no one type of exercise has more effect,” says Dr Johnson. The best approach? “Vary your exercise to include activities like stretching, playing a game of tennis or adding weights, stairs, hills or short bursts of jogging to your walk.”
Myth: Sit-ups will reduce my tummy fat
“Fat loss caused by exercise occurs all over the body, so sit-ups may tone and strengthen your abdominal muscles but won’t magically reduce belly fat,” says Dr Nathan Johnson, exercise physiologist at Sydney University. (In fact, the marketers of the heavily advertised Ab Circle Pro exercise machine were fined $25 million in the US for deceptive advertising.)
Myth: Middle-aged spread is inevitable
You don’t awake one morning to notice your jeans won’t do up ñ this slow weight creep occurs over years. “Middle age spread is not inevitable - what happens with age is that we move less but eat the same or even more and this leads to weight gain,” says John Wentworth from the Centre for Obesity Research and Education at Monash.
The power of the mind
Take time out for 30 minutes of daily meditation and eat more mindfully – women who tried this shed kilos without dieting, according to one study at the University of California. And those who calmed down the most from their ‘ohm’ time, lost more belly fat.