How Your Brain Affects What You Eat

I recently attended a nutrition symposium presented by the Harvard Medical School called "Your Brain Can Help You Eat Better." The sessions were all extremely interesting and each warrant their own post, but in the meantime I wanted to give a brief summary of a few things that I got out of some of the talks that I was able to attend. Hopefully they'll give you something to think about next time you reach for that large bowl or consider whether or not you really have time to exercise...

Primary Obesity: Automatic Effects of Food Marketing presented by Jennifer Harris, PhD, MBA

Take away: During studies done at Yale's Rudd Center for Food Policy and Obesity they discovered that when food advertisements were shown to kids during a TV show, the kids ate 45% more. Adults shown snack ads also ate more. Seeing food ads caused people not just to eat more during the show that they were watching, but after as well. Pre-schoolers were given the exact same food; one from a package with a cartoon character and one in a plain package. They thought that the one coming from the package with the character tasted better.

Thought for Food: How Imagined Consumption Reduces Actual Consumption presented by Carey Morewedge, PhD

Take away: Imagined consumption reduces actual consumption. People who imagined consuming 30 M+Ms (one by one) then ate fewer M+Ms than those who imagined eating either three or none at all. Thinking about something like a spider can cause the same affect in your body as actual seeing it in person; the same is true with food, if you think about the look, taste, and smell it can have a similar affect (in your brain) as eating it, so you'll then actually consume less.

Effects of Exercise on Brain and Cognitive Function presented by Kirk Erickson, PhD

Take away: Exercise, even modest amounts, and even if you don't start until later in life, can:

• increase brain volume (even after just 6 months!)
• improve cognitive function
• increase functional connectivity
• increase brain perfusion
• improve task-evoked brain function

The more fit the person, the greater the volume of the hippocampus. However, the exercise must be aerobic (vs stretching/toning). There is not yet a good understanding of why the brain is getting bigger.

A Limited Resource Model of Self-Control: Implications for Eating Better presented by Kathleen D. Vohs, PhD

Take away: The more you use self-control in one situation, the less self-control you have left in the next situation. For example, if you're told to suppress emotion when watching a sad movie, then you are given food, you'll eat more than if you weren't told to suppress emotion (this is if you're actively dieting).

Combating the Sugar, Salt and Fat Addiction presented by David Kessler, MD

Take away: You can probably read this for yourself in his book The End of Overeating: Taking Control of the Insatiable American Appetite. He looked at why we're so overweight now vs in the past. One reason is that the barriers are gone: food is available 24/7 and on every corner. People in the past would never have eaten walking down the street, in their cars, in class, etc. Another point is that processed food, which has lots of salt, sugar, and fat, is self-stimulating and addicting. There's a lot more than that and it's all very interesting so definitely check out his book.

Mindless Eating: Why We Eat More Than We Think presented by Brain C. Wansink, PhD

Take away: This was probably one of my favorite presentations. I had learned about a lot of his studies in my nutrition classes already. You should also check out his book, Mindless Eating: Why We Eat More Than We Think. Based on studies that he has performed, you should:

• Eat out of a smaller bowl (you'll eat more out of a bigger bowl even if you don't like what you're eating)
• Put the healthy options at eye-level in your cupboard (you're more likely to eat what you see first)
• Only eat in your kitchen or dining room (in one case study even just putting a fruit or vegetable on the table, not necessarily eating it, caused a couple to lose weight)
• Think about the layout/design of the places you eat most and how that might affect the choices that you make (see his article in the Washington Post about getting kids to eat better in a school cafeteria without them knowing it)
• Not necessarily trust your stomach to tell you that you're full (in a study with refillable soup bowls participants said that they were not full because they thought that they had only eaten a half of a bowl of soup).

So, as you can see, there is a lot to think about when it comes to how your brain affects what (and how much) you eat! If you're interested in watching the webcast of these talks, they'll be posted soon here.