SODAS WITH SUGAR LIGHT UP THE TEENAGER'S BRAIN

In spite of what some teenagers think, their brain is still developing, and will continue to develop until they’re an adult.  This may help explain what a mother once shared with me, a woman with seven children (six sons), who said she lost her sons at the age of 13 but got them back when they turned 20.  In the same vein, you’ve seen the bumper sticker: “No need to Google, Ask my teenager, He knows everything.”  The mother said it in a lighthearted facetious way but there may be more truth in it than is commonly thought.

The fact that a teenager’s brain is still in development is the scientific curiosity upon which a recent preliminary study was performed to answer this question: What is occurring in the developing adolescent brain in response to drinking sugar?  The concern for trying to explain the epidemic childhood obesity is what moved the researchers to this question.

There are several areas of the brain that regulate food intake.  One particular spot is in charge of motivation and reward (the putamen and caudate).  Interestingly, during adolescence these particular areas of the brain are undergoing significant developmental changes.  Stimulation of these areas of the brain result of course in motivation and reward.

The study, presented at the recent American Diabetic Association Scientific Sessions in San Francisco, and being preliminary, examined 14 lean adolescents and 20 lean adults.  The mean age of the teens in the study was 16 and that of the adults was 31.  All subjects came in fasting, then drank a high sugary drink.  A before and after functional MRI scan was obtained.  Here’s what they found.

In the lean adults, the before and after MRI revealed essentially no change in blood flow to the motivational and reward areas of the brain, and in several of them the blood flow was actually reduced.  However, in the lean adolescents’ brain there was a marked increase in blood flow to these areas.  A previous study by the researcher of this study, Dr. Ania Jastreboff of Yale University, revealed that obese (not lean) individuals exhibited increased activation in the motivational and reward areas of the brain when they ate their favorite foods (Diabetes Care 2013; 36).

The hypothesis gleaned from these results is that the differences in brain response to sugar ingestion might contribute to teenagers’ higher consumption of added sugars, as well as explain why some, if not many, children/teens are prone to obesity that stays with them through adulthood. 

If you have a teenager living with you, who buys the groceries in your house?  Typically, it’s the mother.  And do you have a teenager in your house from whom you hear the whine of “be sure and pick up the Pepsi, Oreos, and ice cream – Love ya!”  Well, you can tell them you are caring about their brain and instead buy apples, peaches, and grapes.  They can drink water with lemon, milk, or tea w/o sugar.  When they become full-fledged adults, brains fully developed, then they can do what they want and if they aren’t obese by then will have a better chance, more likely than not, in avoiding obesity.  At least as a concerned parent you would not have unwittingly (or not) contributed to their obesity as an adult.  But being the responsible parent, shouldn’t you think twice about getting the colas from the grocery store in the first place, or at least restricting them significantly, say only to be drank on weekends perhaps.

This interesting medical fact, how our brains actually undergo a physical change as a result of our behavior, as well as our thinking, is a fascinating one.  In a later blog I’ll describe how this particular fact explains certain adult behavior surrounding what is probably the most burning issue of our time.