In a Purdue University study, researchers find that drinking highly caffeinated energy drinks triggers changes in the adolescent brain similar to taking cocaine.
Moreover, the consequences can last into adulthood as an altered ability to deal with rewarding substances. The results are in the journal Alcohol.
Researchers focused on the effects of highly caffeinated energy drinks and highly caffeinated alcohol in adolescent mice.
These alcohol studies cannot be performed in adolescent humans, but changes seen in mouse brains with drug abuse have been shown to correlate to those in humans.
Energy drinks can contain as much as 10 times the caffeine as soda and are often marketed to adolescents. But little is known about the health effects of the drinks, especially when consumed with alcohol during adolescence.
In the study, the researchers found adolescent mice given highly caffeinated energy drinks were not more likely than a control group to drink more alcohol as adults.
But when those high levels of caffeine were mixed with alcohol and given to adolescent mice, they showed physical and neurochemical signs similar to mice given cocaine.
It seems the two substances together push them over a limit that causes changes in mice’s behavior and changes the neurochemistry in their brains.
In addition, the researchers also detected increased levels of the protein ΔFosB, which is marker of long-term changes in neurochemistry, elevated in those abusing drugs such as cocaine or morphine.
Furthermore, those same mice, growing into adults, showed a different preference or valuation of cocaine. They were less sensitive to the pleasurable effects of cocaine.
While this sounds positive, it could mean that such a mouse would use more cocaine to get the same feeling as a control mouse.
To test that theory, the researchers examined if mice exposed to caffeinated alcohol during adolescence would consume higher amounts of a similarly pleasurable substance-saccharine, an artificial sweetener.
They found that the caffeine/alcohol-exposed mice drank significantly more saccharine than mice exposed to water during adolescence. This confirms that the caffeine/alcohol-exposed mice must have had a chemical change in the brain.
The researchers plan to continue studying the effects of legal, available psychostimulatory substances that may be harmful to adolescent brains.
News source: Purdue University.
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