Sparing developing countries the fate of obesity-associated diseases that plague the developed world is currently one of the most pressing global public health issues. Before we export wholesale the ‘follow the food pyramid, exercise, and eat no more calories than you burn’ approach, it may be time to review how effective it actually is. The answer is: not very, if a recent study by the Institute for Health Metrics and Evaluation at the University of Washington, showing that the obesity rate continues to climb even as Americans are exercising more, is anything to go by.
I recently came across the work of Peter Attia (like a lot of interesting people, I came across him via his TED talk) on obesity, diabetes and insulin resistance. He is currently exploring a novel hypothesis: that obesity is not a cause of diabetes; rather, it’s a symptom of a much deeper underlying problem. Turning conventional wisdom about diabetes on its head, Attia asserts that adding fat cells could be the lesser of two metabolic evils for a body being bombarded with excess insulin and faced with a choice between using it or storing it.
Attia is now in a team of researchers looking at the causes of obesity from multiple angles, but his, that refined carbs, the culprit of insulin resistance are the problem, is one that makes a lot of sense. Attia is the co-founder of the Nutrition Science Initiative, a non-profit research organization in San Diego. The other co-founder is Dr Gary Taubes, who recently wrote extensively and eloquently in an essay for the BMJ on how little real science is behind the energy imbalance theory of obesity and on the endocrine hypotheses that have been lost in the mists of time.
Obesity is not the only health issue that stands to benefit from a better understanding of the causes and effects of insulin resistance. As a public health researcher and writer, I study the factors that make it difficult for so many women in high-income countries to successfully initiate and sustain exclusive breastfeeding. There are many factors at play, from hospital practices to the attitudes and behaviours that travel along women’s own social networks, and not least the pervasive onslaught of propaganda from the formula industry. But recently published research into the role of insulin in milk production points to sub-optimal glucose metabolism impairing breastfeeding. The research adds to the body of knowledge and clinical trials now underway to test whether diabetes medications can be used to regulate insulin action in the mammary gland. However, the ideal approach is a preventive one, says Dr Laurie Nommsen-Rivers, a scientist at the Cincinnati Children’s Hospital Medical Centre and corresponding author of the study. “Modifications in diet and exercise are more powerful than any drug.”
It’s heartening to see Taubes’ work in the BMJ and Attia garnering the massive publicity that a TED talk can bring. Probably the most famous critic of sugar is Robert Lustig and his work on the health impact of fructose, and there are voices within the medical community trying to get the dangers of sugar on the public health agenda, such as Laura Schmidt and Clare Brindis (see the opinion piece from Schmidt on CNN.com and Nature for the underlying academic paper). Still, it is fat, and saturated fat in particular, that is touted as the main dietary public enemy, and the all-pervasive presence of sugar and refined carbs does not attract similar criticism.
There are pharmaceutical interventions for diabetes and obesity, all with their own side-effects and none offering a cure. Yet there are simple, side-effect free dietary changes that can tackle the underlying issue of insulin resistance. They aren’t lucrative for anybody, except perhaps whole food retailers. Neither the pharmaceutical industry nor the agri-industrial complex will be promoting these changes any time soon. But the public health community can, and arguably should.
Jane Parry is a Hong Kong based public health and medical journalist and researcher.
24 July 2013