When I started running 6 1/2 years ago, the impetus was first to lose some weight and second to get into shape. A combination of slow running and resistance training was enough to get me about 1/2 of the way to my goal, but it wasn’t until I started tracking my caloric intake with LoseIt! that I hit my desired weight.
It took me only six months to lose the 25 or so pounds (which works out to a reasonable rate of one pound per week). What worked for me was simply generating a steady calorie deficit, which I was able to do without feeling like I was sacrificing much. I didn’t go low carb, or high protein, or low fat.* Even as I was responding to the conventional advice of “eat less, move more,” I tried to keep in mind that what worked for me wasn’t necessarily universally applicable. It was therefore surprising to me to see that some popular diet strategies made seemingly grandiose claims about, for example, how carbohydrates were solely responsible for fattening Americans.* Yet, there are plenty of people who’ve reported success with low carb diets, though that could simply be that low carb = fewer calories.
* Hmm, if this is true, why is the rural population in China so thin when the primary staple is white rice?
Anyway, in The Hungry Brain: Outsmarting the Instincts that Make Us Overeat, Stephan J. Guyenet takes his Ph.D. and expertise in neuroscience to tackle the question, why have Americans gotten heavier and bigger in the last few decades? Rather than approach the issue from a macronutrient perspective (i.e., do we eat too many carbs, or is it saturated fat that makes us fat?), Guyenet starts with the brain and evolution. Loosely stated, his thesis is that calories were extremely hard to come by for homo sapiens for the vast majority of our time on Earth, so our brain is hard-wired to make us grab them whenever they are available, and preferably in the most calorie-dense form. Up through the mid-1900s, when food still required a fair amount of effort to gather (farming) and prepare (home cooking), it was hard to take in excess calories in proportion to caloric expenditure. However, once it became easier to make tasty, calorie-dense food shelf-stable, and therefore available at the local supermarket, and once restaurants – especially fast-food – spread throughout America, it’s become easier to gorge on calories. And because of the evolutionary hard-wiring, we have a hard time resisting.
In other words, Guyenet’s answer for why Americans (as a group) have gotten heavier is that cheap food is plentiful and available, and our brains make us overeat. I’m oversimplifying, of course, and Guyenet includes chapters on the effect of stress, sleep deprivation, and more. As a whole, it’s a compelling explanation, and he includes discussions of empirical studies that seem to back up the thesis. (Experimental subjects who were provided their nutrition entirely through bland food do not overeat; they take in enough calories to maintain their weight and no more.) Moreover, Guyenet writes in a lively, clear style, without condescending or judging the reader. If you’re sold on his explanation, he offers suggestions for how to resist the brain’s urges. Some may seem fairly obvious after you’ve read the book, but I’d say that’s an indication of how plausible his explanation is, because if the suggestions really were that obvious, people would be implementing them already. (One example – make it hard to get junk food to eat. Don’t keep it in the house, or if you do, put it somewhere where it will take real effort to get to.)
As for the tie-in to running, check out Alex Hutchison’s latest “Sweat Science” column, How Much Does an Extra Pound Slow You Down?