Food fights

In its dogged pursuit of “health for all,” the World Health Organization is now chasing two of the biggest health hazards on the planet: unhealthy diets and insufficient exercise. The Global Strategy on Diet, Physical Activity and Health was mandated by the World Health Assembly in May 2002 with the objective of reducing the global burden of noncommunicable disease, which now accounts for some 60% of deaths and 47% of illness worldwide. The WHO considers that “[u]nhealthy diets and physical inactivity are ... the leading causes of the major noncommunicable diseases, including cardiovascular disease, type 2 diabetes and certain types of cancer.”1 These problems are not restricted to affluent nations, but are rapidly gaining ground in the developing world, particularly among the young. In Thailand, 15.6% of 5 to 12 year olds are obese. Of the 177 million people in the world with diabetes, two-thirds live in developing countries.

The WHO is calling on governments around the world to implement policies in their ministries of health, food and agriculture that will promote healthy diets and adequate exercise. Suggested ways and means range from public education to market incentives, smarter urban planning, and regulations in food manufacture, labelling and advertising. After consultation with governments, agencies and the private sector, the WHO released a draft document in December, aiming for final adoption at the World Health Assembly in May 2004.

But not without a struggle. The WHO Executive Board has entertained requests for revisions and delays, receiving submissions from such worthies as the World Sugar Research Organization and the European Vending Association (posted on www.who.int/hpr/gs_comments.shtml). The former complains that the WHO has failed to produce evidence that “marketing and consumption of sugary snacks … exacerbate the problem of chronic diseases related to overweight and obesity.” The latter warns that banning vending machines from schools will have the disruptive effect of forcing students to graze off-site. The Salt Institute has weighed in with the judgement that hypertension is merely a risk factor, and therefore not a legitimate target in disease prevention. But the most fascinating submission comes from the US Department of Health and Human Services (DHHS).2 This document begins with a 6-page lecture on evidence-based research, and then proceeds to a detailed list of quibbles and corrections, ostensibly taking issue with the scientific basis of the WHO strategy. The DHHS finds insufficient evidence to support the belief that the heavy marketing of “energy-dense foods or fast-food outlets and high intake of sugar-sweetened soft drinks” increase the risk of obesity, and no data to show an association between television advertising and unhealthy eating habits in children.

Any attempt to use gaps and irrelevancies in science to discredit common sense raises questions about the role that evidence plays in the politics of public health. Evidence has been described as a critical tool to help legislators and policy-makers connect the dots of public policy.3 Perhaps so, but let's be clear about its limits. Public health policy choices are political and moral as well as pragmatic; when those choices are justified by the absence of evidence, their underlying values become more apparent. Clearly visible in the DHHS critique is a libertarian approach to public policy — an approach that overemphasizes “personal responsibility and an individual's role” in making choices2 and places too much faith in unregulated market forces to foster collective health and welfare.

The WHO strategy is a bold one, and we hope that it will withstand industry's self-serving critique. It urges us to revise our disease-by-disease approach to prevention by targeting common determinants of health. To do so, we will also need to revise some of our pharmacocentric habits. As an example: recently published guidelines for the prevention and treatment of diabetes (a 140-page document sponsored by a drug manufacturer) tackle the problem of early detection and screening at length while devoting only 500 words to prevention — over half of which discuss a single prevention trial using a drug, metformin.4

The WHO strategy is a much-needed call to look at the bigger picture of disease prevention and health, and we agree that its implementation “could lead to one of the largest and sustained improvements in population health ever seen.”1— CMAJ