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The Biology of Addiction: Drugs and Alcohol Can Hijack Your Brain

People with addiction lose control over their actions. They crave and seek out drugs, alcohol, or other substances no matter what the cost—even at the risk of damaging friendships, hurting family, or losing jobs. What is it about addiction that makes people behave in such destructive ways? And why is it so hard to quit?

NIH-funded scientists are working to learn more about the biology of addiction. They've shown that addiction is a long-lasting and complex brain disease, and that current treatments can help people control their addictions. But even for those who've successfully quit, there's always a risk of relapse. Research shows that many people will relapse before they overcome addiction—it is not failure, but often a step in the road to recovery.

"A common misperception is that addiction is a choice or moral problem, and all you have to do is stop. But nothing could be further from the truth," said George Koob, PhD, director of NIH's National Institute on Alcohol Abuse and Alcoholism. "The brain actually changes with addiction, and it takes a good deal of work to get it back to its normal state. The more drugs or alcohol you've taken, the more disruptive it is to the brain." The good news is that both behavioral treatments and medications can help bring the brain back into the normal state, noted Dr. Koob.

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Lack of Sleep May Increase Diabetes Risk

A lack of sufficient sleep reduces the body's sensitivity to insulin, impairing its ability to regulate blood sugar and increasing the risk for diabetes, according to researchers from the University of Colorado. Their new study adds to a growing body of information linking a lack of sleep to a range of ailments including obesity, metabolic syndrome, mood disorders, cognitive impairment, and accidents.

"We found that when people get too little sleep it leaves them awake at a time when their body clock is telling them they should be asleep," said the study's lead author, Kenneth Wright Jr., PhD, professor of integrative physiology at CU-Boulder. "And when they eat something in the morning, it impairs their ability to regulate their blood sugar levels."

Diabetes rates are skyrocketing nationwide, noted study co-author Robert Eckel, MD, an endocrinologist and professor of medicine at CU-Anschutz. By 2050, he noted in a press release about the study (, as many as 33 percent of all Americans may have type 2 diabetes.

The study, funded in part by NIH, appeared online in the journal Current Biology (

Keep Your Mouth Healthy: Oral Care for Older Adults

Oral health is important for people of all ages. But the simple routine you learned as a kid—brush your teeth twice a day and floss regularly—can become more of a challenge as you get older. Among adults ages 75 and up, about one in four has lost all natural teeth, largely because of gum disease and tooth decay.

You can take steps to keep your mouth healthy throughout your lifetime. And if you're a caregiver for an older adult, you can help ensure that he or she gets proper oral care. Tooth decay and gum disease don't have to be a part of getting older.

"We have to worry about the same conditions throughout life, although some conditions are more prevalent at certain ages," said Dena Fischer, DDS, MSD, MS, a dental health expert at the National Institute of Dental and Craniofacial Research. "Gum disease is more common when you're older," Fischer explained. "But cavities can happen at any age, as long as you have natural teeth." Both are largely preventable with proper care.

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Winter 2016 Issue: Volume 10 Number 4 Page 28