Putting the Greater Dimensions of Obesity into Perspective

Tackling a complex disorder as a physician or researcher can be frustrating if the etiology of the respective disorder is unknown and no curative treatment is available. Many modernday disorders fit into this category, obesity being one of them. Our impatience and frustration at times tend to obscure the fact that medicine is a constantly evolving field, which is clearly influenced by social and political factors. While true breakthroughs are rare, small steps forward are being taken at a daily level. In comparison to just a few decades ago we have made progress into combating both cancer and cardiovascular disorders. Lifestyle changes such as tobacco control were important in achieving these improvements as were true advancements in specific medical specialties. Clearly some of these changes were brought about by exerting pressure on specific interest groups, sometimes even supported by physicians [e.g. 1]. But just consider that over the last 50 years, the survival rates for childhood cancer have risen from 10% to almost 80% [2]. These advances typically apply to post-industrial countries. The health care systems of developing countries are not capable of providing complex and expensive treatments that are usually accessible in developed countries. Furthermore, despite substantial reductions in smoking rates in affluent countries, recent global estimates nevertheless place the mortality burden from tobacco use at over 6 million annually, with nearly two thirds of these deaths occurring in developing countries [3]. Even within affluent countries it is not only obesity that occurs more frequently in the less privileged. Instead many different somatic and mental disorders occur more commonly in individuals of a lower socioeconomic background. The focus on obesity obscures the dire truth that health and life expectancy depend on education and earnings. The fact that social inequality starts exerting its effects prenatally [4] all the more underscores this problem. We must be careful to not misuse obesity to point to the relationship between social status and health. Obviously, medicine and biology by themselves provide no remedy; the problem is a long-standing one, which indeed requires input from many different fields. In this context, obesity has only recently entered the picture; it should additionally be noted that in the USA socioeconomic disparities in overweight have changed over time, with an overall trend of weakening [5]. The causal evidence underlying the statement that obesity is the negative side of success and prosperity in our modern Western world is thus limited [6]. And yes, it indeed can be argued that inequality represents a huge challenge for the scientific community. But I would also argue that we already have a good idea of what could be done to reduce the impact of the effect of socioeconomic factors on health. It seems that both politicians and voters for whatever reasons shun away from these issues. Improvements of prenatal and postnatal environments of disadvantaged children obviously require vast financial resources. Obesity-related research has begun to take off in the 1990s as a result of the growing awareness of the obesity epidemic. Thus, the total annual number of PubMed articles pertaining to the search term ‘obesity’ has increased more than ten-fold from 1980 and 2009 (table 1); obesity articles started to increase relatively between 1990 and 1995. Between 1990 and 2009 the relative increase was approximately equivalent to 375%. In 2009 about 1.6% of all publications pertained to obesity. We have definitely grown at an impressive level, but we nevertheless need to be well aware of the fact that increased research efforts just began a mere 20 years ago. Compare this relative recent upsurge with the much longer research tradition for cardiovascular disorders or cancer! Thus, 118,340 publications in 2009 are picked up using the search term cancer, which is equivalent to almost 14% of all publications. We have made substantial progress in the elucidation of peripheral and central pathways involved in body weight regulation. These past two decades have taught us that mutations in single genes can cause extreme obesity. We now know that overexpression or knockdowns of many different genes affect body weight in rodent models. Genome-wide association studies have taught us that polygenic variants are difficult to detect and have small effect sizes and that those currently