How can drug addiction help us understand obesity.pdf

F E E D I N G R E G U L AT I O N A N D O B E S I T Y COM M E N TA RY e c How can drug addiction help us n e i c s o r u understand obesity? e n e r u t Nora D Volkow Roy A Wise a n / m o c e. To the degree that drugs and food activate common reward circuitry in the brain, drugs offer powerful tools for understanding the r u neural circuitry that mediates food-motivated habits and how this circuitry may be hijacked to cause appetitive behaviors to go awry. t a n . w w w Until recently in our evolutionary history, physiological stimulation of reward pathways contribution to the variability of smoking in / / : p addictive agents have been ingested in foods. by drugs not only stamps in response habits women is greater now than in earlier decades t t h Many are secondary plant metabolites that and stimulus preferences, but also triggers when social restrictions on females were p evolved because they discourage ingestion by neurobiological adaptations that may make stronger and fewer women tried cigarettes3. u o animals1. The hungers that arise from bodily the behavior increasingly compulsive and lead Just as the genetic influences in addiction vary r G needs are non-directive; they merely encourage to further loss of control over intake. between cultures with differential availability g n us to put things in our mouth. The more acute Not all humans who are exposed to habit- of alcohol, so too is the genetic contribution i h the hunger, the greater the range of substances forming drugs become addicted, just as not to obesity likely to differ between societies s i l we will ingest2. We learn to return to the yellow all humans who are exposed to high-fat, high- that differ in the