Everyday exposure to obesity-promoting chemicals (obesogens) represents a significant risk to public health, and needs stronger regulation to minimise exposure and protect people's health, according to Dr Leonardo Trasande (Professor of Pediatrics, Department of Pediatrics at NYU Grossman School of Medicine, New York), an internationally renowned leader in environmental health.
Speaking at the 59th Annual European Society for Paediatric Endocrinology Meeting, Trasande outlined the evidence for the serious impact of these chemicals on childhood and adult obesity, as well as the global economy. He made recommendations for simple policies that would safely reduce people's exposure, whilst having economic benefits.
The long-held mindset that diet and physical activity are the sole determinants of body weight has now been overturned, and it is understood that genetics and environmental factors also have an important role. However, the damaging influence of hormone-disrupting chemicals on the increasing incidence of obesity has been greatly underappreciated. A rapidly growing body of evidence indicates that these chemicals can scramble our normal metabolism and undermine our natural processes for using calories, predisposing us to weight gain.
Trasande and colleagues have published a number of studies on the adverse effects of human exposure to these chemicals, investigating the long-term effects, from pre-birth into adulthood, of a large, well-characterised Dutch population. In his presentation, he presented compelling evidence from these and other studies on the seriousness of exposure to obesogens, including the dangers of three very common chemicals that we often encounter in our everyday lives. For example, Bisphenols, found in aluminium can lining and thermal receipts, make fat cells larger and predispose us to store fat. Phthalates, found in personal care products and food packaging, can reprogramme how our bodies metabolise protein, pushing it to store fat, regardless of our physical activity level or diet.
PFOS, found on non-stick cookware and water-resistant clothing, have been shown to misprogramme the body to store fat, even when external conditions indicate you should burn fat calories, such as in cold temperatures. In adults that lost weight following a healthy diet with physical activity, higher PFOS levels were associated with more regain of weight later.
"The old 'calories in, calories out' mantra for obesity prevention neglects the crucial role of chemical exposures as a third leg of the stool,” explained Trasande. “In contrast to diet and physical activity interventions, which can hard to be implement, let alone, sustain, levels of obesogens in food packaging and other materials can be modified through regulation.”
It is estimated that endocrine-disrupting chemicals cost Europe €163 billion a year, around 1.2% of its gross domestic product, obesogens are a large part of that.
"Increased obesity caused by these chemicals has a substantial economic cost to society and exposure needs to be minimised for health benefits and to avoid the economic costs of inaction, it is clear that improved regulations are essential,” he concluded.