A recent study in laboratory rats shows that binging on sugar can induce the same changes in behavior and brain chemistry as addictive drugs such as cocaine, morphine, and nicotine. This may come as no surprise to those of us who can’t seem to get enough of the holiday treats this time of year.

Researchers at the Princeton Neuroscience Institute had previously demonstrated that sugar met two of the three elements of addiction: causing a pattern of increased intake over time and signs of withdrawal. The present study, reported at the annual meeting of the American College of Neuropsychopharmacology in Scottsdale, Ariz., provides evidence that sugar binging can also cause the third element of addiction: craving and relapse.

In the study, laboratory rats that binged on sugar and then were denied it for a prolonged period, worked harder to get sugar when it was reintroduced to them. They consumed more sugar than they ever had before, suggesting that they had been craving the sugar and relapsed when it became available. Their motivation for sugar had apparently grown during the time they were without it.

As further evidence of craving, when the researchers offered alcohol to rats who were abstaining from sugar, the sugar-fed rats drank more than normal rats, demonstrating that their sugar binging had changed their brain chemistry. This inclination to overuse other drugs of abuse is common in people with addictions.

The rats also became hyperactive after receiving a very small dose of amphetamine (“speed”) that typically has no effect on normal rats. Increased sensitivity to stimulants is a long-lasting brain effect that can be a component of addiction.

The researchers had previously shown that sugar-bingeing rats undergo neurochemical changes in the brain that appear to mimic those produced by substances of abuse, including cocaine, morphine and nicotine. A chemical neurotransmitter known as dopamine is released in a region of the brain known as the nucleus accumbens when hungry rats drink a sugar solution. This chemical signal is thought to trigger motivation and, eventually with repetition, addiction.

While there is no evidence that sugar is addictive in people, additive behaviors and brain changes induced by other drugs are very similar between humans and rats. So does this mean you should cut out the holiday treats entirely? The rats in the study all binged on sugar several times before becoming “addicted,” so if humans are similar to rats in this regard, you should probably avoid eating large amounts of sugar all at once. Having a piece of fudge after dinner in probably fine; having a tray of fudge, may not be.

For more information or help with addiction, join the Healia Health Community for Substance Use and Chemical Dependency.

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