LONDON – The global obesity pandemic needs addressing on a global level with governments around the world taking the lead, according to a series of papers published in the Lancet.
The series is published ahead of the United Nations High-Level Meeting on Noncommunicable Diseases being held in New York next month. This U.N. meeting is set to discuss what can be done to prevent and control four key disease areas – cardiovascular diseases, cancers, chronic respiratory diseases, and diabetes – for which obesity is a known contributing or exacerbating factor.
“In many ways, the holy grail for governments today, certainly in the United Kingdom, across Europe and the United States, is improving health care while at the same time reducing costs; that's the paradox of modern health care today,” said Dr. Richard Horton, editor of The Lancet, during a press briefing to highlight the Lancet Obesity Series.
Dr. Horton added: “So far, obesity had been stubbornly resistant to traditional public health approaches, and what this series tries to do is to look at the reasons why that might be and how we might get out of that public health 'cul-de-sac' that we are in today.”
The first article in the series (Lancet 2011;378:804-14) looks at the factors that might have contributed to the rising rates of obesity seen around the globe in the past 4 decades. As rates of obesity have risen steadily and simultaneously in many countries, “that points to global drivers,” said the paper's lead author Dr. Boyd Swinburn, professor of population health and the director of the World Health Organization Collaborating Centre for Obesity Prevention at Deakin University, Melbourne.
“There is quite a lot of evidence coming out that this is largely driven be changes in the food system,” which produces a food supply comprising “increasingly processed, available, affordable, and highly promoted, 'tasty' food,” Dr. Swinburn observed.
With both high- and low-income countries affected, the solution appears to lie more with policy changes to try to improve individuals' local environments rather than try to change the public's behavior.
“Support for individuals to counteract obesogenic environments will continue to be important, but the priority should be for policies to reverse the obesogenic nature,” Dr. Swinburn and his colleagues reported.
The lead author of the second article (Lancet 2011;378:815-25), Dr. Y. Claire Wang, noted that if historical trends continue, there could be 65 million more obese adults in the United States alone by 2030, with 11 million more obese adults projected at the same time point in the United Kingdom.
This would bring the total of obese individuals to be 164 million and 26 million, in each country, respectively and, taken together, could result in 6 million to 8.5 million new cases of diabetes, 5.7 million to 7.3 million cases of heart disease and stroke, and 492,000-669,000 additional cases of cancer in both countries.
“We project that the medical costs will be substantial,” said Dr. Wang, of the department of health policy and management at Columbia University, New York. Indeed, the cost of treating essential preventable diseases that result from obesity are estimated to increase by $48 billion to $66 billion per year in the United States and by £1.9 billion to £2 billion per/year in the United Kingdom by 2030.
However, a 1% reduction in body mass index across the U.S. population could avoid up to 2.1 million to 2.4 million new cases of diabetes, 1.4 million to 1.7 million cardiovascular diseases, and 73,000-127,000 cases of cancer by 2030. Similar reductions could be achieved in the United Kingdom.
“Of course, what we have to do is to reverse this [rising obesity trend],” said Kevin Hall, Ph.D., the lead author of the third article in the series (Lancet 2011;378; 826-37). But it may not be as simple as “eat less, exercise more” suggested Dr. Hall, a senior investigator at the National Institute of Diabetes and Digestive and Kidney Diseases.
Standard guidance for weight loss is to reduce caloric intake by 500-1,000 kcal/day to lose 1-2 pounds per week, but this is fundamentally wrong. “The reason it's wrong is that it would only be true if nothing else happened to your metabolism,” Dr. Hall maintained.
Dr. Hall's research shows that for every 10 calories that can be cut from the diet per day, there would more likely be a drop of just 1 pound over 3 years, so not eating a 250-calorie chocolate bar per day could would lead to a 25-pound weight loss over 3 years.
Dr. Hall presented a web-based model that could one day help clinicians advise their patients on how many calories would need to be cut from the diet and the level or exercise needed every day to attain a certain weight loss. Currently, the model can only be used as a research tool and will need to be updated as new data become available.