Diabetes is a metabolic disorder. It is a chronic condition which occurs when the pancreas does not produce sufficient insulin, a hormone that regulates blood sugar, or when the body cannot effectively use the insulin it produces, as a result of which the amount of glucose (sugar) in the blood is too high (hyperglycaemia). There are two types of Diabetes:
Type 1 (formerly called insulin-dependent or childhood-onset diabetes), characterised by absolute insulin production deficiency. Type 1 diabetes usually appears before the age of 40 and is the least common diabetes, accounting for between 5-15% of all cases of diabetes.
Type 2 (previously know as non-insulin-dependent or adult-onset diabetes), characterised by relative insulin deficiency, due to insufficient insulin production or the body’s ineffective use of insulin. Type 2 diabetes usually appears in people over the age of 40, and is the most common of the two diabetes types, accounting for 85 -95% of all cases of diabetes.
Gestational diabetes arises, which arises during pregnancy.
Signs of diabetes include: increased thirst (polydipsia), extreme tiredness, weight loss, blurred vision, excessive excretion of urine (polyuria). Over time the consequence of diabetes include heart, blood vessel, eye, and kidney and nerve damage.
According the World Health Organisation (WHO) more than 180 million people have diabetes across the world. They predict this number will double by 2030.
Figure 1 Number pf people with diabetes (20-79 age group) by region, Diabetes Atlas, Second Edition  Enlarge the picture
Worldwide, the annual direct healthcare costs of diabetes, for people in the 20-79 age-bracket, is estimated to be at least 153 billion international dollars. The total direct medical costs of Type 2 diabetes in the eight European countries was estimated at EUR 29 billion a year (1999 values) .
Risk factors for Type 1 diabetes are unknown. However, both genetic and environmental influences are suspected of playing a role. It is thought that an environmental trigger stimulates an immune attack against the insulin-producing pancreas beta cells in genetically susceptible individuals.
Risk factors for of Type 2 diabetes include: having a close family member with Type 2 diabetes, high blood pressure, excess body weight, physical inactivity and ethnicity.
As a result of globalisation dramatic changes have occurred in the environment and to lifestyles. The rapid rise in incidence of diabetes, coupled with the disturbing clustering of diabetes with other well-known cardiovascular disease (CVD) risk factors such as obesity, suggests environmental and lifestyle factors, rather than genetics, are the principal contributors to the diabetes epidemic.
The lifestyle risk factors for diabetes are well established. However, recent evidence suggests that toxins may also be involved, interfering with glucose and insulin metabolism. The chemical culprits include dioxins and endocrine disrupting chemicals (EDCs) like Bisphenol A (PBA), substances known to interfere with the body’s hormone system, linked to the actions of insulin. , , 
In addition to these studies, chemicals are further implicated by the link with risk correlates that influence major risk factors rather than contributing to the absolute risk of diabetes, such as hypertension, cholesterol, or obesity. For example, research suggests there is a link between obesity and exposures to chemicals that mimic estrogens (xenoestrogens). Since obesity is a risk factor for Type II diabetes, these chemicals can also be considered indirect linked to diabetes.
Further research into the causes of Type 1 diabetes is clearly needed. However, with more than half of the European population predicted to suffer from Type 2 diabetes during their lifetime and its clustering with CVD and obesity, preventive measures to reduce disease incidence are urgently needed to reduce the escalating public health burden. Measures to reduce obesity and increase physical activity are vital. However, given the increasing evidence linking chemicals to obesity, diabetes and CVD, a precautionary approach that aims to reduce exposures to certain chemicals is also warranted.
For more information in Obesity please see the relevant web pages of the Chemicals Health Monitor.
 Alonso-Magdalena, P, S Morimoto, C Ripoll, E Fuentes and A Nadal (2006) The Estrogenic Effect of Bisphenol-A Disrupts the Pancreatic ß-Cell Function in vivo and Induces Insulin Resistance, Environmental Health Perspectives, Volume 114, Pages 106-112
 Lee, D-H, I-K Lee, K Song, M Steffes, W Toscano, BA Baker, and DR Jacobs (2006) A Strong Dose-Response Relation Between Serum Concentrations of Persistent Organic Pollutants and Diabetes. Results from the National Health and Examination Survey 1999–2002, Diabetes Care, Volume, 29, Pages 1638-1644.
 Rene B. J. Remillard and Nigel J. Bunce (2002) Linking Dioxins to Diabetes: Epidemiology and Biologic Plausibility, Environmental Health Perspectives, Volume 110, Number 9