Thursday, October 11, 2012

Dopamine and Appetite/Genetics and Exercise

Ever since I was around six years old, I knew I was different.  Where my brothers and sisters were content with two cookies, one piece of cake, or even one reasonable slice of meat, I always wanted more.  Unless it was meatloaf, but that's a meatloaf issue.

By seven years old, when I started swim team with my sister, I discovered something was really wrong with me.  No matter how hard I tried or how much I pushed myself, I was worn out after swimming one length of the pool.  I had plenty of energy for playing on the playground, especially when it came to tether ball, jumping rope, or foursquare, and I could ride my bike on the flat like a champ- no hands most of the time, but when it came to biking up hills, running, or swimming, everyone else passed me like I was standing still.

To make things even more odd, I simply adored dancing.  I could dance around the living room, skip, and gallop down the hallways with joyful abandon, but skipping and dancing don't get you picked for any teams at school.

What was going on with the way I ate and the way I moved?  If we look at eating, I was born in the first generation that regularly ate sugar for breakfast.  I remember Capn Crunch, Froot Loops, and Trix being three of my favorites, and it usually took two bowls to satisfy me.  I was a small kid, why did I need to polish off two big bowls of cereal?  The answer may lie in the neurotransmitter dopamine.  In my latest issue of "Fitness Journal" I read an article by Dr. Pamela Peeke on how dopamine and it's receptors are affected by food.  Dopamine is connected to the pleasure we feel while eating, and the urgency we feel when we think about food.

I was not surprised at all that studies of obese subjects showed that they had fewer dopamine receptors than the lean individuals who were studied.  The lack of receptors was likely a cause of greater and more urgent appetite, and an effect from overeating.  In the same way that we can become insulin and leptin resistant, we may also become dopamine resistant.  What's the worst offender when it comes to messing with dopamine?  Sugar appears to be enemy number one, and when you mix it with fat and salt look out- edible crack.

On top of the dopamine response, sugar acts on the same parts of the brain as cocaine and heroin, and the cravings and obsession it causes can lead to the kind of behavior that packs on pounds of fat in spite of the best intentions of the susceptible individual who eats it.

What solutions does Dr. Peeke offer to this dilemma?  She cites meditation to lower stress and cravings because it builds up the Prefrontal Cortex of the brain, an area that is responsible for "Executive Functions" like organization, creativity, and self control.  She also writes about the power of exercise to increase beneficial neurotransmitters like BDNF.  On the nutrition front, omega 3s are helpful in their ability to keep dopamine receptors healthy.

For the past four years I have managed my cravings and obsessions with a diet that's low in sugar, white flour, grains, and processed fats.  I meditate daily, and as a personal trainer I teach my clients the forms of exercise I love and that leave me feeling energized and vital, not worn out and wondering why everyone is going faster and farther than me.

Here is the affiliate link to the program that turned me into the athlete I always wanted to be on my terms: Turbulence Training For Fat Loss.

In my next post, I will write about what it means to be a "Non Responder" to endurance  exercise, and why that absolutely does not have to keep you from building your authentic ideal body.