Placing the blame for obesity on specific foods or drinks is to miss the real cause of the problem – and to overlook simple solutions.
“The main cause of obesity in Western countries is low socio-economic status, or poverty,” Adam Drewnowski, Professor of Epidemiology at University of Washington, Seattle told health professionals at the International Sweeteners Association conference, Why Calories Count, in Brussels this week (02-04-14).
Often media headlines blamed obesity on high calorie sweetened drinks one day and then low calorie sweetened drinks another day. “How can that paradox be true?” asked Prof Drewnowski. “I suggest the cause of obesity and associated type 2 diabetes (T2D) and other health problems is something else.”
Something as surprising as your postcode. “Most obesity and T2D is found in lower socio economic status (SES) groups,” said Prof Drewnowski who has used newly available health insurance data in the US, combined with census information, to produce the first ever maps of obesity rates and T2D by census tract.
“These detailed geographical maps show that obesity and T2D reside almost exclusively in high poverty areas,” said Prof Drewnowski whose work pinpoints obesity street by street.
“The problem is that type of data we analysed does not exist in the EU, and is not widely available in the UK, although some British researchers are looking into it.”
It was important to do this type of mapping worldwide in the fight against obesity “ so that health interventions can be targeted in the neighbourhoods where they are needed,” said Prof Drewnowski.
Obesity hotspots cannot be explained by anything other than SES, said Prof Drewnowski. “Scientists may have identified single gene disorders, hormone and other physiological or behavioural disturbances associated with obesity, but people with them do not all live next door to one another in concentrated groups,” said Prof Drewnowski.
Obesity hotspots are more accurately identified by average house prices, he contended. “House prices and tax returns predict diet quality and health, and that applies worldwide.”
“If you live in a $1m house it seems it doesn’t matter what you eat, you are unlikely to be obese,” joked Prof Drewnowski who also pointed out that those with the highest incomes and highest levels of education were also the biggest users of low calorie sweeteners.
“Most obese groups don’t use low calorie sweeteners” so they are missing out on a motivating weight loss tool, said Prof Drewnowski.
People who do use low calorie sweeteners have higher healthy eating scores than non-users, revealed Prof Drewnowski by analysing US National Health and Nutrition Examination Survey (NHANES) data. “They are eating fewer ‘empty calories’, more vegetables, fruit and whole grains, and are more physically active and less likely to be smokers.”
“Low calorie sweetener use continues to go up after age 35 and its increasing use among older people correlates with a decrease in obesity seen with aging,” explained Prof Drewnowski.
So if low calorie sweetener users are more likely to be overweight, it is not because using sweeteners is causing their weight problems, it is because they are using sweeteners to lose or manage their weight, explained Prof Drewnowski. “This is an example of reverse causality.”
“Low calorie sweetener users among the richer better educated groups also have no safety concerns about their use,” observed Prof Drewnowski.
“Low calorie sweeteners are then a proxy for better health behaviour and lifestyle.”