July is National Diabetes Week so this month our focus is on diabetes, Australia’s fastest growing chronic disease, which is estimated to affect 1.7 million Australians. In fact, 280 of us are diagnosed each day – that’s one every five minutes. And many people with type 2 diabetes remain undiagnosed.
While the statistics paint a gloomy story, there is some good news. Type 2 diabetes is largely preventable and because in most cases it develops slowly, this presents plenty of opportunity to intervene and reduce your risk.
Type 2 diabetes: what goes wrong?
Diabetes is a condition where there is too much glucose (or sugar) in the bloodstream. When we consume carbohydrate (starchy and sugary foods) our body breaks them down into glucose (the body’s main energy source), which enters the blood stream. Insulin (a hormone produced by the pancreas) is needed for the absorption of glucose by the body’s cells. Diabetes occurs when the body doesn’t produce insulin or when the insulin that is produced doesn’t work effectively.
Type 2 diabetes, which is by far the most common form, affects 85-90% of all people with diabetes. While it’s more often diagnosed in older adults, due to our increasing rates of obesity, we are now frequently seeing young children with type 2.
The development of type 2 diabetes begins with a condition called insulin resistance, where the body’s insulin is unable to work properly. Initially, the body makes extra insulin to overcome this resistance, so blood glucose levels remain normal. But if nothing is done to reduce the extra workload on the body’s insulin producing (beta) cells, eventually they can’t keep up and blood glucose levels start to rise. Basically, the beta cells can no longer produce enough insulin to overcome the resistance.
As blood glucose levels rise, you progress from insulin resistance to impaired glucose tolerance or impaired fasting glucose, both also known as ‘pre-diabetes’. This is where blood glucose levels are above normal but not high enough to be diagnosed with diabetes. At this stage, lifestyle changes, moderate weight loss and possibly the use of medication can significantly reduce the risk or delay the development of diabetes. Without intervention, however, it is likely that blood glucose levels will continue to rise and progress to type 2 diabetes within 5-10 years, or sometimes sooner.
Why prevention matters
Unfortunately research has found that by the time many people are diagnosed with type 2 diabetes they have already lost up to 80% of their beta-cell function. In other words, only 20% of their body’s insulin producing capacity is left. This means that lifestyle changes may not be effective for long, and diabetes medications might be needed at the time of or soon after diagnosis, with many people progressing to needing insulin to manage their diabetes within a few years. Of particular concern is that many people with type 2 diabetes already have early signs of complications such as eye, kidney and nerve damage, by the time they are diagnosed.
Diabetes complications occur when the blood glucose levels remain elevated for periods of time – these complications include heart disease, kidney disease, eye damage and circulation problems. If diabetes is diagnosed early and blood glucose levels are kept well managed, with lifestyle changes and the addition of medication when needed, the risk of developing these complications can be significantly reduced. So early diagnosis, and maintaining blood glucose levels as close as possible to the normal range, as well as managing cholesterol and blood pressure, is the key.
As the symptoms of diabetes (such as thirst, frequent urination, blurred vision and fatigue) don’t usually kick in until the blood glucose levels are quite high, awareness of risk factors is the key to early diagnosis of type 2. That’s right – the key to preventing diabetes and its complications is not to sit around and wait for it to happen but to get in early and do everything possible to ward it off. And the best way to do this is with lifestyle changes.
Lifestyle is key – proof is in the research.
While genetics play a part, and we can’t change our genes, type 2 diabetes is also a lifestyle disease that is more common in people who are overweight and inactive. It makes sense, then, that diet and exercise might help to prevent this condition from occurring in the first place. The good news is that we have proof that this is the case and the benefits are significant.
Several studies have now shown the benefits of lifestyle intervention for preventing diabetes but the best evidence comes from two large studies, one in the USA (called the Diabetes Prevention Program, or DPP) and another in Finland (called the Finnish Diabetes Prevention Study) which both found that people with pre-diabetes who took part in a lifestyle intervention program reduced their risk of developing diabetes by 58%. This means you can more than halve your risk of developing diabetes just by improving your eating habits, walking regularly and losing a few kilograms.
Of note, the US study found that lifestyle changes were twice as effective as medication in preventing diabetes. Even if you already have diabetes, making these changes will help you to manage your condition, may delay or reduce your need for medication, and can help to reduce the chances of long-term complications.
So if you want to take control of your health, now is the time to take action!
Diabetes prevention in 6 easy steps
Here are the lifestyle changes that matter:
Move more. It’s well established that regular exercise can significantly reduce diabetes risk. A combined analysis of 10 studies carried out by researchers at the Harvard School of Public Health found that compared to those who were sedentary, people who regularly participated in moderate intensity physical activity had a 31% reduction in risk of type 2 diabetes. And those who walked briskly for at least 2.5 hours each week had a 30% lower chance of developing diabetes than those who did almost no walking. These findings were similar in men and women and were independent of weight. And if you need more motivation to get moving, check out our blog post Motivation to Exercise with some tips to get you started.
Sit Less. It’s not just about regular exercise – even sitting less can help. Australian research has linked television watching and time spent in sedentary activities with a higher risk of raised blood glucose levels. Other studies have found that breaking up prolonged sitting (even for a minute or two every 20-30 minutes) can improve insulin sensitivity and glucose tolerance. Obviously sitting is bad for our health but even small changes can make a difference!
Adopt a plant-based diet. Eating habits have a vital role to play when it comes to your risk of developing type 2 diabetes. Limiting total energy intake to manage your weight is important but the types of food you eat also matter. Diets high in saturated fat, red meat and processed meats have been linked with an increased risk of diabetes while diets high in fibre, wholegrains, legumes, nuts and vegetables are associated with a reduced risk. This means basing your meals around plant foods (vegetables and salads, legumes, wholegrains and nuts), eating more fish and legumes in place of red meat, choosing only lean cuts of meat and avoiding processed meats. One large study found that a Mediterranean diet (which is consistent with these recommendations) reduced the risk of diabetes by 52% in those with cardiovascular risk factors. Similarly, a number of studies have found that those who follow a vegetarian or vegan diet are significantly less likely to develop diabetes. Not sure where to start? Check out or Pinterest recipe board for some inspiration.
Reduce your waist measurement. Carrying excess weight increases the risk of diabetes, particularly when it’s around the middle. If your waist measurement is above 80cm for women or 94cm for men, you are at much higher risk of developing diabetes. The good news is that losing just 5-10% of your weight can significantly reduce your risk of developing diabetes.
If you smoke, quit now. We all know that smoking isn’t good for us and can increase the risk of heart disease and cancer, but most people don’t realise that it can also increase your diabetes risk. Studies have shown that smokers are more insulin resistant and have an increased risk of developing type 2 diabetes. One large study of more than 4000 men found that compared to those who had never smoked, those who smoked up to 20 cigarettes per day had a two-fold increase in risk of developing diabetes while those who smoked 20 cigarettes or more each day had a 2.4-fold increase in risk.
Get a good night’s sleep. Lack of sleep has been shown to worsen insulin resistance and studies have shown that both sleep quality and quantity are related to diabetes risk. A combined analysis of 10 studies found that sleeping less than 5-6 hours/night increases the risk of diabetes by 28% while sleeping more than 8-9 hours increases the risk by almost 50%. The same study also found that difficulties getting to sleep and difficulties maintaining sleep were associated with a 57% and 84% increase in risk of diabetes, respectively. In those with diabetes, too little or too much sleep is associated with higher blood glucose levels.
Diabetes – are you at risk?
If you answer yes to one or more of the following questions, you are at higher risk of developing diabetes, so it’s important to discuss this with your doctor:
- I have a family history of type 2 diabetes
- I have high blood pressure
- I have high triglycerides and low levels of good (HDL) cholesterol
- I have heart disease or have had a heart attack
- I am overweight, particularly around the middle
- I am over 55
- I am of Chinese, Indian or Pacific Islander Heritage
- I am an Aboriginal or Torres Strait Islander
- I have Polycystic Ovary Syndrome (PCOS)
- I had diabetes in pregnancy or gave birth to a large baby (over 4.5kgs)
- I don’t exercise regularly or get much activity in my day
You can also check out your risk online with the AUSDRISK interactive tool – by answering ten questions based around the risk factors above, you will be able to calculate your risk of type 2 diabetes in the next 5 years.