For centuries, being overweight was a sign of wealth and prosperity; an indication that one had access to plenty of food when most people were poor and probably starving.
As we enter 2021, the world faces an obesity epidemic, where excess body-fat is no longer a symbol of high socio-economic status, but is rather a symptom of automation, industrialisation and urbanisation.
Relatively speaking, until very recently, humans have spent most of their time gathering, hunting or growing food to sustain themselves, whilst struggling against famine, disease, war, pestilence, drought and of course, poverty. With the coming of the second industrial revolution in the 19th century, came a focus on productivity. The health, strength and body size of the workforce was seen to be linked to economic and military power, so in the early 20th century efforts were made by industrialists and governments to supply high calorie, low cost, processed food, to the working classes. The availability of processed foods, consisting mainly of fats and sugars, together with a slow but consistent rise in the standard of living, led to a gradual increase in the average body size of the population of developed countries over the following decades. The average height and weight of people in industrialised countries rose incrementally through the 19th and 20th centuries, but as heights reached their maximum potential, weights continued to grow, leading to an increase in the average Body Mass Index (BMI).
The improvement in the standard of living in western industrialised countries had come at a cost. The obesity issue has been growing exponentially since the 1980s and as at the year 2000, the number of overweight adults exceeded the number of underweight adults for the first time in history. Inexpensive, high calorie foods have played their role, but another factor, courtesy of the rise in the standard of living, is the sedentary lifestyle. The urbanisation that has accompanied our economic progress often promotes car use, restricts time and space for exercise, inhibits the opportunity to grow food, provides 24 hour access to low quality processed food and encourages long hours of TV and electronic device use.
Children are uniquely affected within this obesity issue, as their nutrient requirements are much higher than those of adults. Low-cost processed food may not provide adequate nutrients to meet growth demands yet deliver excess calories, resulting in overweight, malnourished, children.
In recent decades, the ubiquity of obesity has broadened to include urban areas of developing countries such as India, Mexico, Thailand, Brazil and China. As was the pattern in western nations, obesity was more prevalent in the wealthy populations at first, but has since become much more common in lower socio-economic households, where cost plays a greater role in purchasing behaviour. Given the numerous health implications associated with being overweight or obese, such as hypertension, type II diabetes, heart disease, immobility, some cancers and stroke, the public health burden this portends is massive.
Whilst it is ultimately the behaviour of the individual that is the determining factor in weight regulation, it is undeniable that these socio-economic forces have a huge impact. We, together with our leaders and governments, have a responsibility to educate the next generation and shape global health policy, in order that this worrying epidemic may be curtailed.