A century ago the major cause of deaths was infectious diseases. With the advent of medicine the number of deaths due to infectious diseases has reduced but illnesses that are more chronic and metabolic have risen in number. Chronic diseases now account for the majority of deaths especially in developed countries.

Depression and anxiety

There is a connection between chronicity, or long term nature of illnesses, long life span and mental illnesses as well.

The prevalence of mental health disorders in the United States, for example, has increased over the past several decades and nearly 6.6% of the US adult population (more than 13 million adults) have a major depressive disorder and about 18% (about 40 million adults) have an anxiety disorder.

Depression and anxiety thus form the major chunk of mental health problems in the United States as well as in other developed nations.

Prevalence of obesity

Obesity is on the rise as well. Among US adults, prevalence of obesity, as defined as a body mass index or BMI of 30 or more, was nearly 23% in 1990 and 31% in 2000.

Obesity and other conditionsThe numbers have steadily increased over the past decade as well. The increases have been consistent across both genders, across all age groups, and across all racial/ethnic groups.

Obesity raises the risk of diabetes, arhtiritis and cardiovascular disease leading to shortened life span and more importantly a poorer quality of life.

Depression and associated unhealthy behaviors

Depression and anxiety are associated with unhealthy behaviors including:-

• Smoking
• Alcohol abuse
• Drug or substance abuse
• Poor diet
• Physical inactivity
• Disturbances of sleep

There is evidence that risk of engaging in these behaviors is higher among people with certain psychiatric conditions like depression and anxiety. Some of these behaviors are also common and prevalent among obese individuals.

Obesity and depression and anxiety

There are studies that reveal that obesity is associated with an increased lifetime risk for major depression and anxiety disorders.

Obesity also raises the risk of panic disorder or agoraphobia, particularly among females.

Excess alcohol consumption, poor diet and physical inactivity have been associated with depression as well as obesity.

Studies have shown that among middle-aged women, obesity is strongly associated with depression. This association among populations remains consistent even after adjusting for other factors such as race, marital status, educational attainment, tobacco use or antidepressant use.

Depression is further associated with significantly lower physical activity levels and higher caloric intake.