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March 29, 2013


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BALINTFY: Welcome to episode 188 of the new NIH Research Radio. The new NIH Research Radio is your source for weekly news and information about the ongoing medical research at the National Institutes of Health – NIH . . . Turning Discovery Into Health®. I'm your host Joe Balintfy, and coming up in this episode our news summary at the end of the program includes items on how overweight or obese people with serious mental illnesses can lose weight, and differences in gaze may be an early warning for autism.

But first, our feature story...

Regular marijuana use by teens continues to be a concern

BALINTFY: The 2012 Monitoring the Future survey has shown that teens continue use marijuana at a high rate and this is combined with a drop in perceptions of its potential harms. Wally Akinso files this report.

AKINSO: Marijuana usage continues to be an issue among teens in the 8th, 10th and 12th grades. 

VOLKOW: We have seen significant increase over the past year in the prevalence of marijuana abuse particularly among 10th and 12th graders.

AKINSO: Dr. Nora Volkow is the director of NIH’s National Institute on Drug Abuse.

VOLKOW: For example for the 12th graders, past month of marijuana use went from 19 percent to 23 percent, which is basically a 15 percent increase. And actually even more noteworthy are the increases that we have seen in daily using of marijuana which are at the highest since we started this survey.

AKINSO: The 2012 Monitoring the Future survey was conducted by researchers at the University of Michigan.  It’s an annual survey and has been around since 1975.

VOLKOW: The survey is conducted across the whole United States.  It comes out of a sampling in approximately 45,000 kids that are either in 8th, 10th or 12th grade across 395 high schools throughout the United States. 

AKINSO: Monitoring the Future survey also showed that teens’ perception of marijuana’s harmfulness is down which can signal future increases in use.

VOLKOW: The survey also asks about attitude and beliefs regarding the dangerousness of drugs.  And in the case of marijuana for example we have seen a change towards negative, vis-à-vis, negative indicators in that we have less teens believing that marijuana is harmful.

AKINSO: As teens get older, their perception of risk diminishes.  Only 20.6 percent of 12th graders see occasional use as harmful, the lowest since 1983, and 44.1 percent see regular use as harmful the lowest since 1979.  Research shows that marijuana has the potential to cause problems in daily life or make a person’s existing problems worse.

VOLKOW: What we know factually is that the use of marijuana can result in addition and this was something that in the past was not believed to be the case.  But now based on clinical and pre-clinical evidence it is clear that marijuana can produce addiction. 

AKINSO: Dr. Volkow adds that the risk of addiction goes from 1 in 11 overall to about 1 in 6 for those who start using in their teens, and even higher among daily smokers.  For more information on the Monitor the Future survey, visit  For NIH Radio, this is Wally Akinso.

BALINTFY: You can also find information about the Monitoring the Future survey at the website: Coming up, helping the 80% of people with serious mental illnesses who are overweight or obese lose weight, and understanding how an infant’s gaze may help diagnose autism. That’s next on NIH Research Radio.


News Summary

BALINTFY: Now for some recent news headlines from NIH, here’s Craig Fritz.

FRITZ: According to a study funded by NIH, people with serious mental illnesses such as schizophrenia, bipolar disorder and major depression can lose weight and keep it off through a modified lifestyle intervention program. Over 80 percent of people with serious mental illnesses are overweight or obese, which contributes to them dying at three times the rate of the overall population. Although many medications for serious mental illness can increase appetite and cause weight gain, it is not the only culprit. Like the general population, sedentary lifestyle and poor diet also play a part. Lifestyle modifications such as diet and exercise should work for these patients, yet they are often left out of weight loss studies due to their illness.

Researchers supported by NIH have found that children who are later diagnosed with autism, take a split second longer to shift their gaze during a task measuring eye movements and visual attention than do typically developing infants of the same age. The difference between the groups’ test results was 25 to 50 milliseconds on average, too brief to be detected in social interactions with an infant. However, scientists showed that this measurable delay could be accounted for by differences in the structure and organization of actively developing neurological circuits of a child’s brain.

For this NIH news update, I’m Craig Fritz.

BALINTFY: You can get more information on these news items and find much more at

And that’s it for this episode of the new NIH Research Radio. Please join us again next Friday, April 5th, when our next edition will be available. Coming up in that episode…

Because dietary supplements are used by half of adults, we wanted to understand the reasons why people were using these products.


BALINTFY: If you have any questions or comments about this program, or have a story suggestion for a future episode, please let me know. Send an email to Also, please consider following NIH Radio via Twitter @NIHRadio, or on Facebook. Until next week, I'm your host, Joe Balintfy. Thanks for listening.

ANNOUNCER:  NIH Research Radio is a presentation of the NIH Radio News Service, part of the News Media Branch, Office of Communications and Public Liaison in the Office of the Director at the National Institutes of Health in Bethesda, Maryland, an agency of the US Department of Health and Human Services.