Following the government's "Decade of the Brain" push, all HCPs should have at least a minor working knowledge of this reward system.
Essentially, says Guyenet, having lots of different tastey foods available means you can always choose foods that will maximize your dopamine reward from eating. Like a junky needing bigger doses of cocaine to get high, Americans with global cuisines and processed foods full of fat and sugar at their disposal at any time need to overeat to get their fix. Thus, obesity.
Although I think there's something there, I am skeptical for a number of reasons, including:
- Conceptually, there is a black box between food reward and overeating. Until the brain-mind-behavior connection is explicated more fully, I would be wary of attributing too much to symplistic feed-back models. Especially when, unlike cocaine, the connection between biochemistry of rewarding food and brain circuits is tenuous.
- Practically, this takes us no-where in moving forward in public health/primary care. From a healthcare perspective, a "Food Reward" theory is not fundamentally more complex or informative than saying that people eat too much because they like food and don't control themselves. The question why some people get fat from Food Reward is like the question why some people become coke addicts: you get bogged down in all sorts of behavioral questions and political assumptions. I made this criticism on Stephan's blog and another commenter responded by falling back on some sociological research, which just proved my point.
- Practically, on an individual basis, a 'Food Reward Diet' essentially says "lose weight by not eating the things that appeal to you." Needless to say, this is a losing strategy for weight loss.
- Importantly, it doesn't explain adequately to me the data, whether from research or N=1. For example, as I pointed out on Stephan's blog, Gina Kolata points to research showing that both skinny and fat people engage in emotionally-driven eating. This suggests that other factors mediate in the gain of body fat. Also, how did I lose all that weight on the Atkins Diet and then later, again, eating my own modified Paleo Diet (meat, greens, wine, booze, and dessert restricted to ice cream), when I ate all I wanted?
Donut? Ravenously hungry. Bread? No, not hungry now. Bread with Nutella? Meh...
Also, I ask myself, current circumstances notwithstanding, why are my donut cravings in general reduced when I cut out bread?
To me, my experience raises the question whether there are necessary and sufficient eating conditions for manipulating any food reward system. Stephan essentially recommends eating bland, hard-to-prepare foods. Maybe it is sufficient just to cut out some forms of carbs? Or maybe it is necessary to cut out some forms of carbs?
My personal upbringing was one in which a quasi-hippie mother shopped at a local food co-op. I never had sugary breakfast cereals, candy, cookies, etc in the home. According to Stephan's poisonous modern culture theory of overstimulation, I should have been one of the fittest and leanest young chaps around. But I wasn't. In fact, anything with carbs from milk to pasta was fair game for snacking. It wasn't until carbs were cut that things got under control. I like fat, but I don't binge-snack on bacon. No desire.
I don't think carbohydrates are physiologically damaging, but so far I haven't seen anything in either the Paleo or Food Reward paradigms that isn't basically taken care of by Atkins, right down to his induction phase (the at-home Betty Ford Clinic of the Food Reward Diet).