According to the Ministry of Health, there are more than 270,000 Kiwis who have type-2 diabetes, and approximately one-third of these cases are undiagnosed. Type-2 diabetes occurs predominantly as the result of an unhealthy lifestyle, however there are other factors to consider.

‘It's our own inaction that's allowing type-2 diabetes to become an epidemic,' says Mike Smith, president of Diabetes New Zealand.

What causes type-2 diabetes?

The hormone insulin is like a metabolic traffic officer, allowing glucose into cells where it's burnt as energy. Too much food creates a traffic jam of glucose in the blood, and that combined with insufficient exercise results in the effect of insulin becoming overpowered, so the glucose that was once a vital food source becomes a demon.

A persistently high level of glucose causes damages to the walls of blood vessels, increasing the risk of blood clots. This can lead to an increased risk of heart attack, stroke, kidney disease and blindness.

The slippery slope

About 500,000 New Zealanders may have pre-diabetes and as with type-2, the insulin simply doesn't work as efficiently, resulting in higher blood glucose levels. Untreated, it may turn into type-2 diabetes after five to 10 years.

Simple detection

Pre-diabetes is often diagnosed by chance. Your doctor may have ordered a fasting blood glucose test as a routine screening, and the results have come back higher
than recommended. You will then have to undergo an oral glucose tolerance test, in which you fast overnight, then drink glucose and have your blood glucose measured over a two-hour period. If glucose is building up in your blood, the diagnosis is pre-diabetes.

What puts you at risk?

Diabetes risk factors include:

A family history of diabetes

A waist measurement greater than 88cm for women or 102cm for men

Lack of exercise

High blood pressure

High LDL or ‘bad' cholesterol, high triglycerides and not enough HDL or ‘good' cholesterol

Polycystic ovaries

If you fall into any of these categories, see your doctor to determine your blood pressure, waist size and your fasting levels of glucose, cholesterol and triglycerides.

What you can do?

A slide towards type-2 diabetes (which is non-insulin dependent) can be halted. If you can reduce your weight by five to 10 per cent, and exercise for more than 30 minutes each day, you may reduce your risk of developing type-2 diabetes by up to 58 per cent. By becoming physically active you will:

Make your insulin work better, lower the glucose in your blood and lower your blood pressure as well as blood fat

Achieve a healthier body weight

Increase the strength of your bones to prevent osteoporosis

Improve your quality of life

Your action plan

If you could be at risk, then here's how to stave off the onset of pre-diabetes. Always talk over an activity plan with your doctor. Half an hour of moderate physical activity
on most days of the week is ideal.

Walking is a refreshing and gentle exercise to start your regimen. Get ready the night before - put your shoes, socks, shorts, shirt and sunscreen at the end of the bed, so when you get up all you have to do is fill up your water bottle, grab your hat and sunnies and off you go. Find a friend to walk with you. If you're too puffed to chat you're walking too fast, if you can sing you're not going fast enough.

Motivate yourself with a pedometer. To stay the same weight, do 10,000 steps a day, to lose a few kilos, slowly work up to 15,000 steps a day. Walk for 10 minutes twice a day for the first week, and gradually progress to longer walks.

To increase the health benefits of walking by 30 per cent, progress to interval or ‘slow then go' training. Start at your regular pace, then increase your speed for a minute or two before dropping back to your usual pace. Increase the interval every other day to add speed-up sections to your walk.

Eat by the rule, ‘Breakfast like a king, lunch like a prince, sup like a pauper.' Have smaller meals, increase your fibre intake, cut out unhealthy fats and opt for lean meats. All meals should have a low glycemic index (GI) to improve metabolism. For breakfast, try wholegrain bread or rolled oats with fruit and low-fat yoghurt and milk. For more information, visit www.diabetes.org.nz.

Knowing the difference

It's vital to note that pre-diabetes heads down the road to type-2 or lifestyle-induced diabetes - quite different  to type-1 or juvenile diabetes in which the body does not produce insulin at all. Mike Wilson, CEO of Juvenile Diabetes Research Foundation in Australia, says, ‘The blame culture around diabetes is unfair, especially in the case of type-1 diabetes, which isn't linked to day-to-day diet or exercise. Type-1 is caused by a mixture of genes and factors in our environment that scientists don't yet fully understand.' What this form of the disease urgently needs is a cure.

A study of 270, 000 men and women on a low-GI diet for nine years found they reduced their risk of type-2 diabetes by 40 per cent.

Visit www.glycemicindex.com for a comprehensive list of low-GI foods.

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