|Conférence Desjardins le 01 October 2008|
|Why we get fat: adiposity 101 and the alternative hypothesis of obesity|
( Professionnels de la santé )
Par: Gary Taubes, NY
| De||12:00 à 13:00|
|Lieu :|| Hôpital Laval - auditorium du pavillon d'youville 2e étage|
|Journaliste auteur du livre Good Calories, Bad Calories: Challenging the Conventional Wisdom on Diet, Weight Control and Disease.
Conférence en anglais Offert aussi en Visio-Conférence au
-CHUL Quebec salle A2804.3 au Centre mère-enfant.
-CSSS Chicoutimi Salle H-1-006
Since the 1950s, obesity has been perceived as a disorder of overeating -- the result of prolonged positive energy balance. Advice to the obese has remained consistent: consume fewer calories than expended and weight will be lost. Reasonable as it seems, this prescription rarely works, suggesting the possibility that the underlying hypothesis is incorrect.
In reality, the argument that obesity is caused by overeating is based on a misinterpretation of the first law of thermodynamics. This law says only that a change in mass (fat) is equivalent to a change in energy of the system. It says nothing about causality. If obesity is fundamentally caused by a regulatory defect driving fat accumulation, and that in turn causes positive energy balance, thermodynamics still holds true.
Prior to World War II, European clinicians argued that obesity was obviously a hormonal and genetic disorder. They evoked a simple metaphor to clarify the causality issue: growing children must also be in positive energy balance. But their growth is not the result of overeating. Rather they overeat because they’re growing. The growth is induced by hormones. The same could be true for the growth of fat tissue.
By this alternative hypothesis, obesity is fundamentally caused by the hormonal dysregulation of adipocytes, and specifically by the consumption of refined carbohydrates, starches and sugars. These foods prompt (directly or indirectly) excessive secretion of insulin, which is the primary regulator of fat storage. Put simply, we do not fatten because we overeat; we overeat because carbohydrates fatten us.