Diabetes is a condition which is characterised by excessive levels of circulating blood glucose (sugar) and can predispose individuals to a plethora of additional conditions if not properly managed. There are three main forms of diabetes type 1, type 2 and gestational diabetes mellitus.
Islet cells in the pancreas counteract rising blood glucose levels by producing a hormone known as insulin. Insulin's role within the body is to transport circulating glucose from the blood stream into skeletal muscle and fat tissue where it can then be stored and used as an energy source for future use. This is an extremely important process as glucose in high concentrations within the blood is toxic and can cause irreparable damage to blood vessels, nerves, and organs.
Diabetes, or prolonged high blood glucose, can occur through a number of different pathways and the mechanism which is causing excessively high blood glucose determines the type of diabetes, either type 1, type 2 or gestational.
Type 1 Diabetes Mellitus
Type 1 diabetes is characterised by the loss of pancreatic islet cells due to autoimmune system dysfunction. The autoimmune system perceives the islet cells to be foreign and attacks them resulting in severely limited or no insulin production. It is currently unknown exactly what causes the body's autoimmune system to perceive islet cells as foreign, however, there does appear to be a genetic link. Typically type 1 diabetes manifests at a young age, although can appear at any stage of life. It should also be recognised that type 1 diabetes is not caused by lifestyle and dietary habits, but both do play a very important role in managing the condition.
Type 2 Diabetes Mellitus
Typically type 2 diabetes is the result of insulin resistance where insulin is still being produced. However, the insulin's function is not adequate enough to maintain normal blood glucose levels (4.4 - 6.1mmol/L). Within the initial phases of the disease, the pancreas increases its insulin production to help counteract the rising blood glucose levels. Unfortunately, this increased insulin production is not sustainable and insulin production decreases over time. Type 2 diabetes can be the result of risk factors, such as, genetic predisposition, poor lifestyle and dietary habits,that increase an individual's chances of developing type 2 diabetes. It should be noted that not all risk factors are avoidable/modifiable. Below are some of the known modifiable and non-modifiable risk factors for type 2 diabetes.
During the early phases of pregnancy, adaptations to hormone levels result in lower blood glucose levels. However, as the pregnancy progresses insulin sensitivity decreases and, as a result, increases circulating blood glucose. To counteract the rise in blood glucose, more insulin is produced, but if insulin production is inadequate, it may result in sustained high blood glucose levels - gestational diabetes.
Modifiable Risk Factors
- Overweight / Obesity
- Physical inactivity
- Poor diet
- High blood pressure
- High cholesterol
Non-Modifiable Risk Factors
- Gestational diabetes - Individuals who were diagnosed with gestational diabetes during pregnancy have a significantly increased risk of later development of type 2 diabetes.
According to the latest statistics from the Australian Institute of Health and Welfare, almost one million Australian's (4.2%) are currently living with diabetes. Of those who have been diagnosed with diabetes, 11.9% are type 1 and 84.9% are type 2. In regards to gestational diabetes, 1 in 20 pregnancies are affected by diabetes.
During 2008-2009, approximately $1.5 billion was spent on treating diabetes in Australia, which makes up 2.3% of all health expenditure. Additionally, 3 out of 5 diabetics were also diagnosed with cardiovascular disease (commonly caused by sustained high blood glucose levels) which placed an additional burden on the healthcare system.
Signs, Symptoms and Detection
The signs and symptoms of diabetes are very similar between all three major forms of diabetes. Type 1 diabetes symptoms may appear significantly faster and more severely, while type 2 symptoms may only be mild and increase slowly over time. These signs and symptoms include:
- Feeling lethargic / fatigued
- Excessive thirst
- Increased appetite
- Frequent urination
- Unexplained weight loss
- Lack of concentration
- Blurred vision
- Slow healing wounds
- Increased susceptibility to infections
- Tingling or numbness in the extremities
- Nausea and stomach pains
- If you are concerned that you may be suffering from diabetes, it is recommended that you consult your doctor to undergo glucose tolerance testing.
Prevention and Management
Unfortunately, due to the genetic factors at play, there are no known ways to reduce the likelihood of developing type 1 diabetes. This is a similar case for some women during pregnancy, where a genetic predisposition makes developing gestational diabetes unavoidable. However, prevention for type 2 diabetes and gestational diabetes (in some women) can be improved by adopting healthy lifestyle choices and limiting exposure to associated risk factors. Below are some helpful tips to enhance prevention and management of type 2 diabetes:
- Be physically active - Exercise can reduce blood glucose levels, even in the absence of insulin, and plays an important role in reducing insulin resistance. Both healthy individuals and people with diabetes should be aiming to achieve a minimum of 150 minutes of moderate intensity physical activity per week. With physical activity being performed 5-7days each week. Additionally, it is also recommended that individuals participate in strengthening activities at least 2 days per week.
- If you have been diagnosed with diabetes please ensure you check with your doctor before commencing exercise. It is also recommended that individuals with diabetes exercise with a partner and ensure blood glucose readings are between 5.6mmol/L - 13.9mmol/L prior to commencing. If you would like more information regarding the amount and type of physical activity you should be performing, please consult your doctor or an exercise physiologist.
- Maintain a healthy body weight - Large amounts of body fat can increase insulin resistance and increase your risk of developing type 2 diabetes.
- Maintain a healthy diet - It is recommended that individuals achieve a minimum of two serves of fruit and five serves of vegetables each day, as well as limiting the amount of saturated and trans fats consumed. If you would like more information regarding healthy dietary habits, please consult your doctor or a qualified dietician.
- Avoid / Cease smoking - Research shows that those who smoke tobacco are twice as likely to develop type 2 diabetes.
- Limit alcohol consumption - Alcohol is high in energy and can contribute to weight gain as well as increases in blood pressure and bad cholesterol. Men and women should limit their alcohol consumption to two standard drinks per day and have at least two alcohol free days per week.
- Have regular health check-ups - As we age it is a very good idea to regularly have your blood pressure, blood glucose levels and cholesterol checked to ensure diseases are diagnosed before they progress and become more severe.
**CLICK HERE to view the Exercise and Sports Science Australia Position Statement on Diabetes and Exercise