Obesity

The burgeoning epidemic of diabetes in Africa will exact a terrible toll from the people and economies of the region. The costs of the condition and its complications are already unacceptably high. Every day in Africa, large numbers of children and adults die because they cannot pay for the insulin they need to survive; many more die before a diagnosis can be made. But diabetes can be controlled through relatively small investments and prevented entirely through simple cost-effective interventions.

In the late 20th century obesity became an epidemic. The importance of obesity as a risk factor for a number of conditions, including type 2 diabetes, cardiovascular disease, hypertension, gallstones and certain cancers, is well documented. Often associated with insensitivity to insulin, obesity is clearly a key factor in the development of the metabolic syndrome – a risk for both diabetes and cardiovascular disease. In this article, Robert Eckel and Scott Grundy explore the underlying causes of obesity and insensitivity to insulin.

It is estimated that around 2 billion children and adolescents worldwide suffer from weight-related disorders. According to the World Health Organization (WHO), more than a billion people are overweight, at least 300 million of whom are obese. As societies continue to embrace unhealthy sedentary lifestyles, fuelled by high-fat, high-sugar processed foods, obesity-related disorders, including type 2 diabetes and cardiovascular disease, are affecting increasing numbers of people at all levels of society and in almost all the countries in the world.

As the number of children with obesity continues to grow, the health implications of the condition are becoming increasingly evident: an unprecedented epidemic of type 2 diabetes is emerging in obese and overweight young people. At the time of diagnosis of diabetes, cardiovascular disease may already be present, even in young adults. The close association between type 2 diabetes and cardiovascular disease led to the hypothesis that the two may arise from a common antecedent, the metabolic syndrome – a cluster of metabolic disorders.

Over the last 30 to 40 years, the death rate from cardiovascular disease has been gradually falling in many countries in the developed world. Improved detection and treatment of high blood pressure and high cholesterol levels, falling rates of smoking, and modern, efficient treatment of emergencies, such as heart attacks, have contributed to a steady decline in the numbers of people dying from cardiovascular conditions. However, according to Jonathan Shaw, this trend could be reversed at the next tick of the global clock.

The drastic rise in childhood obesity worldwide reflects the impact of unhealthy modern lifestyles. Over the last decade and a half, the increase of high-sugar, high-fat processed foods in our diets has combined with sedentary behaviour to radically and negatively affect the health of our societies. Initiatives are urgently required which can reduce the resulting individual and societal burden to physical and psychological health and economic development.

One day in 1997, when he and his family should have been celebrating his wife’s birthday, Guy Barnett’s life changed abruptly: having been diagnosed with type 1

Indigenous Australians have poorer health than the rest of the Australian population; for Aboriginal people, life expectancy is about 20 years less than for the general population. Significantly though, the low expectation of life in Indigenous Australians is less associated with high child mortality, as occurs in many groups in developing countries; the big differences are among young to middle-aged adults.

Compared to people without the condition, people with diabetes are at increased risk from vascular diseases – including heart attack and stroke. This risk is further increased in people with diabetes who smoke; smokers with the condition should be advised by their health carers to stop smoking as a matter of urgency. But giving up the habit is not easy. Successful cessation requires people to surmount a number of difficulties, including strong physical, psychological and behavioural

Treatment with the newly developed drug rimonabant has been found to help to reduce body weight and improve cardiovascular and metabolic risk factors. It has also been shown to help smokers to stop using tobacco without the weight gain often associated with cessation. Beat Lutz reports on the recently discovered body system that links obesity, metabolic disorders and smoking, and the potential of rimonabant as a therapeutic option to tackle these multiple cardiovascular risk factors.