Are we getting fatter because there is just a lot more irresistibly delicious food around us? Does that explain the obesity crisis?
That theory has been around the block but it is in fashion again. In 2009, David Kessler’s book, “The End of Overeating” put forward the thesis that food in contemporary American food has been deliberately engineered–by adding fat, sugar and salt–to exploit our neurochemistry and hijack our free will.
More recently, one of the luminaries of the Paleo movement, Stephan Guyenet, has formulated his own version of this theory, in a compelling series on his Whole Health Source blog, arguing that ”food reward” is a main driver of obesity. His prescription: eat a bland diet. Guyenet’s talk about this at the Ancestral Health Symposium last month is the buzz of the paleosphere.
But I think the theory is wrong, for the simple reason that it too blindly takes correlation for causation. And in doing so, it gets the causal direction mostly wrong. We don’t get fat because food has become too tasty. Rather, to a large extent, it is the metabolism and dietary habits of the obese that make food taste too good to resist, leading to insatiable appetites. And the good news is that we are not consigned to blandness. If we eat and exercise sensibly, we can eat flavorful, delicious foods and enjoy life, without packing on the pounds.
A number of recent weight loss methods have been developed that explicitly recognize a close relationship between flavor and appetite. These methods include:
- Flavor-calorie dissociation as advocated by Seth Roberts in his Shangri-La Diet
- Sensory-specific satiety, as advocated in David Katz’s Flavor Point Diet
- Tastants, another approach to sensory-specific satiety, as advertised in Alan Hirsch’s Sensa Weight-Loss Program.
- Odor inhalers, a third approach based on sensory-specific satiety, as described in Alan Hirsch’s book Scentsational Weight Loss, and marketed by him as ”diet pens” offered by SlimScents
At first, some of these approaches appear to be mutually incompatible. The Shangri-La theory argues that strong or familiar flavors enhance appetite when they become associated with caloric foods. The other three approaches, by contrast, claim that intense flavors or aromas suppress appetite, based upon the principle of “sensory-specific satiety”, whereby an increase in the intensity of a single flavor or odor induces satiety. However, on closer examination, all of the above theories are consistent with one another, as I will try to show. Furthermore, they each provide some useful clues about how to achieve a long term weight loss and relief from hunger cravings by paying attention to the role of flavor and other food cues. Finally, as I will attempt to persuade you, only one of the above diets is truly a type of Deconditioning Diet that can lead to long term, permanent reduction in appetite, based on the principles of Hormetism.