There are a plethora of reasons why you should talk to your teens about the dangers of underage drinking. One study even shows that teen boys, in particular, may experience an increased risk of developing aggressive prostate cancer later in life. 
In a recent study, men who reported consuming at least 1 alcoholic beverage a day between the ages of 15 and 19 had more than triple the odds of developing aggressive prostate cancer in adulthood, compared to non-drinkers.
The study doesn’t prove that drinking during adolescence causes prostate cancer; however, it may be a marker of other risky behavior, including heavy drinking in adulthood.
Yet, senior researcher Emma Allott said that because the prostate grows more quickly during adolescence, it’s possible the organ is more vulnerable to cancer-causing agents during adolescence.
“We are still at the point where there isn’t really convincing evidence linking alcohol and prostate cancer risk. But potentially, there could be a role for alcohol early in life.”
Allott said she hopes the study will lead to more research into prostate cancer risk factors over a man’s lifetime, instead of just a focus on a man’s risk in adulthood.
For the study, Allott and her colleagues questioned 650 ex-servicemen aged 49 to 89 who were having their prostate biopsied for possible cancer about their weekly alcohol consumption during each decade of life. 
Men who reported drinking 7 “standard” U.S. drinks – each the equivalent of a bottle of beer or a glass of wine – during their teen years were 3.2 times more likely to develop aggressive prostate cancer than men who said they never drank during adolescence.
Men who drank largely the same level of alcohol during their 20’s and 40’s were found to have a similar risk. But once they reached their 60’s, their alcohol consumption appeared to have no impact on whether or not they developed prostate cancer.
Because of the self-reported nature of the study, however, the research had its limits.
Dr. Matthew Hobbs of Prostate Cancer UK said:
“As highlighted by the researchers, these studies are tricky to interpret as they rely on participants’ accurately reporting their drinking and eating habits from a significantly long time ago.
It is also very difficult to single out the impact of drinking alcohol from other factors. We do know that alcohol plays a role in the development of some cancers and should be consumed in moderation.”
In fact, alcohol is linked to at least 7 different types of cancer: 
- 1.Mouth and throat
- 2. Esophagus
- 3. Larynx (voice box)
- 4. Liver
- 5. Colon
- 6. Rectum
- 7. Breast
Professor Jennie Connor, PhD, of the University of Otago in Dunedin, New Zealand, said at the time:
“There is strong evidence that alcohol causes cancer at 7 sites, and probably others.”
Therefore, it is entirely possible that boys who drink alcohol during their teen years face a greater risk of aggressive prostate cancer later in life.
 Daily Mail