Governments could slow - and even reverse - the growing epidemic of obesity by taking measures to counter fast food consumption, according to a study published in the Bulletin of the World Health Organization.
The study, by a team of researchers based in the United States and Ireland, is the first to look at the effects of deregulation in the economy, including the agricultural and food sectors, and the resulting increase in fast food transactions on obesity over time. It suggests that if governments take action, they can prevent overweight and obesity, which can have serious long-term health consequences including diabetes, heart disease, stroke and cancer.
Rather than looking at the density of fast food outlets or self-reported fast food consumption as researchers have done in the past, the authors took the novel approach of taking data on the number of fast food transactions per capita from 1999 to 2008 in 25 high-income countries and compared them with figures on body mass index (BMI) in the same countries over the same time period as an indication of fast food consumption.
A person with BMI of 25 or more is considered overweight, while one with a BMI of 30 or more is considered obese.
The authors of the study found that while the average number of annual fast food transactions per capita increased from 26.61 to 32.76, average BMI increased from 25.8 to 26.4. Thus, each 1-unit increase in the average number of annual fast food transactions per capita was associated with an increase of 0.0329 in BMI over the study period.
"Unless governments take steps to regulate their economies, the invisible hand of the market will continue to promote obesity worldwide with disastrous consequences for future public health and economic productivity," said lead author Dr Roberto De Vogli from the Department of Public Health Sciences at the University of California, Davis, in the United States.
The study focuses on high-income countries, but its findings are also relevant to developing countries as "virtually all nations have undergone a process of market deregulation and globalization - especially in the last three decades," De Vogli said.
The BMI figures also reveal how widespread the problems of overweight and obesity are and that people living in the 25 countries are, on average, overweight and have been for the last 15 years.
The average number of annual fast food transactions per capita increased in all 25 countries. The sharpest increases were in Canada (by 16.6 transactions per capita), Australia (14.7), Ireland (12.3) and New Zealand (10.1), while the lowest increases were in countries with more stringent market regulation, such as Italy (1.5), the Netherlands (1.8), Greece (1.9) and Belgium (2.1).
They also found that the intake of animal fats and total calories changed only slightly at a time of a sharp increase in obesity.
Taking data from the United Nations Food and Agricultural Organization, the authors found that the intake of animal fats decreased slightly from 212 kcal per capita per day in 1999 to 206 in 2008 and that the caloric intake increased slightly for six of those years with 3432 calories per capita per day in 2002 compared to 3437 in 2008. Yet, most men and women do not need more than about 2500 and 2000 calories respectively a day.
"This study shows how important public policies are for addressing the epidemic of obesity," said Dr Francesco Branca, director of the Department of Nutrition for Health and Development at WHO.
"Policies targeting food and nutrition are needed across several sectors including agriculture, industry, health, social welfare and education," Branca said, adding: "Countries where the diet is transitioning from one that is high in cereals to one that is high in fat, sugar and processed foods need to take action to align the food supply with the health needs of the population."
The new study echoes a growing body of literature providing evidence for measures that governments could take to reverse the obesity epidemic by hindering the spread of ultra-processed foodstuffs. Such measures include:
- economic incentives for growers to sell healthy foods and fresh food items rather than ultra-processed foods and subsidies to grow fruit and vegetables;
- economic disincentives for industries to sell fast food, ultra-processed foods and soft drinks such as an ultra-processed food tax and/or the reduction or elimination of subsidies to growers/companies using corn for rapid tissue growth, excessive amounts of fertilizers, pesticides, chemicals and antibiotics;
- zoning policies to control the number and type of food outlets;
- tighter regulation of the advertising of fast food and soft drinks, especially to children;
- trade regulations discouraging the importation and consumption of fast food, ultra-processed foods and soft drinks; and
- more effective labelling systems especially for ultra-processed foods, including fast food and soft drinks.
WHO's 194 Member States agreed on the Global Action Plan for the Prevention and Control of Noncommunicable Diseases at the World Health Assembly in May 2013. One of the plan's nine voluntary targets is to "halt the rise in diabetes and obesity". It also proposes measures that countries can take to tackle obesity, including increasing fruit and vegetable consumption and managing food subsidies and taxes to promote a healthy diet.