Many Australians are overweight – national data suggests around 68% of men and 55% of women are either overweight or obese. This poses a great challenge for our society as being overweight significantly contributes to the risk of poor health. These figures are generated on the basis of body mass index (BMI), which represents a ratio of weight relative to height. For reference, you can check your BMI on the Heart Foundation website or see your healthy age range on the Healthy Weight Guide website. Both are linked below.



Many people are likely to be familiar with unhealthy weight adversely impacting the cardiovascular system, blood-sugar processing, and cholesterol levels, while some may also be aware that being overweight may contribute to breathing issues during sleep. However, being overweight also disrupts many complex hormonal systems in the body, having far wider effects, contributing to poorer health across the entire body.



Although being overweight is the greater population concern, it is important to note that being underweight can also poorly impact health. Some research suggests that one in every six people who are underweight may have similar health hazards as those who are obese.

Despite its notoriety, cholesterol is important for the body – especially in lining the walls of many cells. However, abnormal cholesterol levels remain a great concern with around 32.5% of Australians having abnormal cholesterol levels.



There are two common groupings of cholesterol – LDL (low density lipoprotein), which is often known as “bad” cholesterol; and HDL (high density lipoprotein), which is often known as “good” cholesterol. Although the balance between these “good” and “bad” cholesterols is most important, overall cholesterol levels are also important. In particular, this may be because people with high cholesterol levels often present with higher levels of LDL cholesterol and lower levels of HDL.



Compelling evidence links high cholesterol levels to unhealthy effects on the cardiovascular system. However, cholesterol also increases the risk of many health conditions including diabetes, cancer, and dementia.

Diabetes, or diabetes mellitus in full, is a metabolic disorder characterised by an imbalance between levels of insulin, secreted by the pancreas, and blood sugars.



Insulin plays an important role in the body processing sugars from the blood stream. Thus, in people with diabetes insulin levels tend to be lower and blood sugars higher.



Diabetes is normally discussed with reference to two types: type 1 diabetes is most often acquired early in life and, because it is characterised in deficits producing insulin, typically requires treatment with insulin. Type 2 diabetes tends to develop later in life and is most often influenced by lifestyle behaviours. It is characterised by blood sugars rising rapidly after eating, meaning it may be managed by either insulin treatment or other medications.



Diabetes has many effects on the human body as a whole, and given the association of type 2 diabetes with poor diet and obesity, it can be difficult to determine what factors are diabetic-specific and what are a result of comorbidities (overlap with other conditions).



Nonetheless, diabetes has mechanisms linking it to cardiovascular disease, chronic kidney disease, and dementia, while it is associated with increased onset and reduced survival in several cancers. Diabetes is especially strongly linked to chronic kidney disease – diabetes is believed to cause kidney disease in around 30-40% of people with type 1 diabetes, and around 25% in type 2 diabetes.