This is a shorter version of an article that appears in the latest issue of Perspectives, an opinion-led journal published by Baker IDI Heart and Diabetes Institute.
Maladaption is the inability of a species to effectively adapt and survive in response to changes to its environment. And the current obesity epidemic and its links to chronic disease is the result of a maladaptive lifestyle dominated by too much fat and refined sugars, and too little exercise.
Obesity is emerging as both a major co-morbidity of and precursor to a range of chronic diseases including hypertension, diabetes, metabolic syndrome, sleep apnoea, cardiovascular and musculoskeletal diseases, and certain cancers.
Not everyone will have all these conditions but the vast majority of obese people will have at least one in addition to obesity.
And this overlap is important both at the biological level and when attempting to untangle the causes and optimal treatments for these complications.
Indeed, their link begs a question about whether it’s helpful to categorise and treat individual diseases when they are so critically interrelated.
It may be that we need to come to a different kind of understanding and recognise that probably all chronic diseases have either their origins in, or are enhanced by, a maladaptive lifestyle super-imposed on a patchwork of genetic traits and environmental influences in each individual.
Not all fat is equal
Unsurprisingly, prevention, diagnosis and treatment of such lifestyle disorders is complex.
Educating the public about the dangers associated with obesity is a good start but not all fat is equally dangerous, and not everyone who is obese self-identifies with that description.
Abdominal obesity is actually more dangerous than fat in a pear-shaped body. And even two people with “pot bellies” can fare differently.
Some people carry most of the fat inside their abdominal cavity and metabolically, that seems to impact very negatively on their health. Others carry fat in a superficial layer around the waist, which is less threatening.
So even measuring waist circumference is not a reliable indicator of the risks associated with overweight and obesity, although it is a lot better than just jumping on the scales, or calculating body mass index (BMI).
Complicating matters even further is research showing that some people who are overweight – albeit a very small minority – are quite healthy and never suffer any adverse health consequences, especially if they are fit.
This highlights an identification and risk stratification challenge for physicians and community health professionals.
Out of date tools
Many of the risk guidelines for overweight and obesity we use today are based on the Framingham Risk Score, which was developed in the 1950s, before obesity became such a widespread and endemic problem.
It would certainly be useful to have better diagnostic markers to identify if someone were at risk from excess weight, as opposed to just identifying if they are overweight or not.
Unfortunately, diagnosis of overweight or obesity is not followed with a universally effective treatment either.
Unlike HIV, where a single-message social education campaign on safe sex had a dramatic impact on prevention, the contributing factors to obesity and chronic disease are difficult to distil into a single, succinct message and even more difficult to implement.
No one wants to take on a health problem that is seemingly insoluble but we can take heart from some important initiatives offering a glimmer of hope.
In September 2011 the United Nations, for the first time, hosted a summit on non-communicable diseases. One of the key objectives of the summit was to develop an international resolution on tackling chronic disease.
Until then, it’d been difficult to get chronic disease on the agenda of international health organisations or even the big charities such as the Bill and Melinda Gates Foundation, because of a focus on preventing infectious diseases and the importance of vaccination.
So the summit was a very important step in elevating the issue globally and highlighting the need for a comprehensive and coordinated approach.
We are also starting to see some progressive initiatives by global food manufacturers who, if only for their own enlightened self-interest, have commenced research and development into new products that are less harmful but continue to deliver the same appealing taste combinations that make their products so popular.
The new holy grail for food technologists is creating products and flavour combinations that evoke the same hedonic response as fat, starch and salt, without the negative side effects.
If they can achieve that, then we might reach a stage where we can live with the social and economic changes pushing people toward processed, convenient foods.
Adapt or perish
For all species, adaptation to changing conditions is critical to enable them to survive and thrive.
The rapid pace of lifestyle change experienced by the human species in the last 50 years presents a significant danger to health.
Science has a critical role to play in addressing this challenge and helping the species to adapt.
Whether it’s informing new guidelines about sedentary behaviour in the workplace; developing better diagnostic markers of risk; breakthroughs in treatment and behavioural science; or working in partnership with the food industry to modify foods so they are less harmful, science has an important contribution to make to the adaptation process.