OBESE NATION: It’s time to admit it - Australia is becoming an obese nation. This series looks at how this has happened and more importantly, what we can do to stop the obesity epidemic.
Here Rosemary Stanton reviews two recent books on the subject while Anthony Capon provides an energy system perspective of obesity.
While there’s no doubt about obesity’s increasing prevalence, there are doubts about its importance, its causes and appropriate solutions. And the contrast between views is evident in two new books tackling the topic.
Professor Marion Nestle is no stranger to controversy. Head of the department of nutrition, food studies and public health and professor of sociology at New York University, Nestle is outspoken about the way our food choices are manipulated, most famously expressed in her book Food Politics: How the Food Industry Influences Nutrition and Health. Nestle has teamed with Malden Nesheim, professor emeritus and former director of the division of food sciences at Cornell University to pen Why Calories Count: From Science to Politics.
In Weighing In: Obesity, Food Justice and the Limits of Capitalism, Julie Guthman, associate professor in the community studies department at the University of California, takes a different perspective, querying the extent of the obesity problem and the science and solutions proposed to counter it. Guthman’s expertise is on surer ground in the section of her book where she examines the relevance of neoliberal economic policy to obesity.
Nestle and Nesheim take the traditional approach, assuming that obesity is a problem and citing increased risks of coronary heart disease, high blood pressure, type 2 diabetes, certain cancers (endometrial, breast, colon), stroke, liver, and gallbladder disease, sleep apnoea and respiratory problems, osteoarthritis, and gynaecological problems, such as abnormal menses and infertility.
Guthman acknowledges that Americans are growing fatter but considers the dangers to be exaggerated. She also argues against claims made by Nestle and others that people eat more when food is abundant and cheap. Starting with her own body mass and increased blood glucose levels, which she puts down to environmental toxins or perhaps middle age, Guthman believes factors, such as toxins that disrupt endocrine function, are the major cause of obesity.
For straight science, I can’t go past Nestle and Nesheim’s book. It gives a succinct and scientifically accurate account of the “facts” of energy, it’s textbook-standard, well referenced from peer-reviewed sources and it’s easy and compelling reading with the science softened by practical interpretation.
By contrast, Guthman’s ideas and referencing on straight scientific issues is all over the shop, giving book authors and journalists’ opinion pieces equal billing with peer-reviewed journals. This muddies her challenge of the causes and consequences of obesity.
Experienced interpretation is essential with dietary surveys. If people ate only what they told researchers, the majority of adults in countries such as Australia or the United States would not be overweight. Nestle and Nesheim understand the “struggle to estimate intake” and quote doubly-labelled water studies demonstrating that under-reporting of food intake ranges up to 45%, and is more common in those who are overweight or of low education or income status.
Foods that are perceived as “bad for you” are typically under-reported while many people exaggerate their intake of foods they think are healthy. As Nestle and Nesheim note, the food available for consumption within the United States has expanded, and even allowing for increased wastage, overall consumption has increased. Guthman doesn’t accept this and also doubts “that contemporary jobs involve less toil.”
Twin studies have given us firm evidence of the genetic component of obesity, but also the interactions between the environment and genes. Overfeeding always increases weight, but to different degrees according to genetic factors. Again, Guthman ignores the body of research, declaring that “some people are fat no matter what they do, and some are thin no matter what they do.”
Guthman does acknowledge that Body Mass Index (BMI) has increased in America since 1980, but insists there’s no evidence that people eat more than previous generations, nor that the varying incidence of obesity with socioeconomic status is due to differences in energy intake. Instead, Guthman proposes that the real culprits are environmental toxins used in making and storing the cheap food supply. This includes chemicals used for pest control, livestock growth enhancers (more widespread in the United States, but limited to beef cattle in Australia), plastic containers used for food and water, and synthetic food processing aids.
Scientists, including Nestle, are interested in such issues, but Guthman claims the lack of scientific attention to toxic exposure as the prime cause of obesity is due to a “deep investment in the energy balance model.” Perhaps Guthman should read the documented information in Nestle and Neshiem’s book.
While the level of scientific expertise differs between the authors of the two books, both are critical of the current food system. Nestle and Nesheim concentrate on the “eat more” environment pushed by the need to satisfy food companies’ continued demand for growth and increased profits. Guthman swings into a well-argued section examining the pluses and minuses of various solutions to the current US food system. Smaller farms, local foods, organic foods, “local” foods, “slow food”, school and community gardens and spread of “foodie” ideas get a hammering (often deserved) for the way they are set up and run with virtually no hope of achieving “food justice”.
Guthman offers some challenging arguments, including the validity of using the lens of obesity to view health disparity and food injustice. She argues compellingly on the futility of pushing for better food choices when external factors prohibit such changes occurring among those who really need them.
Of the two books, my inclination favours Nestle and Nesheim’s well presented book. Nonetheless, the latter sections of Guthman’s book provide a compelling perspective on the need to engage with issues of food production and adequate wages and entitlements so that everyone can eat well. I suspect that Guthman’s call to change the emphasis from the market to the state, from consumption to production and from individual castigation of the obese to social justice would also sit well with Nestle and Nesheim.
This is part eleven of our series Obese Nation. To read the other instalments, follow the links below:
Part three: Explainer: how does excess weight cause disease?
Part twelve: Putting health at the heart of sustainability policy
Part thirteen: Want to stop the obesity epidemic? Let’s get moving
Part fourteen: Fat of the land: how urban design can help curb obesity