Concerns are growing over the excessive consumption of caffeine among adolescents, according to a report on Sunday, citing a teen health study.

According to last year’s “Youth Health Behavior Survey” conducted by the Korea Disease Control and Prevention Agency on some 60,000 middle and high school students in 800 schools nationwide, 22.3 percent of the respondents answered “yes” when asked if they drink high-caffeine beverages more than three times a week. Some 26 percent of the respondents said they consume such drinks once or twice a week.

Under the Special Act on Safety Management of Children’s Dietary Lifestyle, which aims to encourage healthy eating habits and nutritionally balanced food, food containing high amounts of caffeine is in the "caution" category for minors under 18.

This is because a large number of students here resort to caffeine beverages like energy drinks and coffee as an aid to cope with long nights of studying, as they give students a temporary energy boost, according to local reports quoting experts. The proliferation of low-priced coffee franchises near schools and private education institutions also appears to have played a part in making it easier for them to access caffeinated beverages, they added.

High-caffeine beverages usually contain over 15 mg of caffeine per 100 ml cup. The Ministry of Food and Drug Safety recommends that adolescents and young children consume no more than 2.5 mg of caffeine per 1 kg of body weight. The recommended maximum daily intake of caffeine for a 50 kg adolescent is 125 mg.

When a teen consumes too much caffeine, it can lead to detrimental health effects and have a negative effect on a teen’s growing body -- producing nausea, sleep impairment, nervousness and even slowing the maturing process of their brains and the ability to concentrate, according to experts. In rare cases, caffeine poisoning can lead to death.

To keep foods high in caffeine out of minors' reach, the Ministry of Food and Drug Safety banned selling high-caffeine foods like coffee in schools in 2014. Warning signs about the side effects of caffeine are displayed on shelves that sell highly caffeinated beverages at around 700 convenience stores near schools in an effort to prevent children from purchasing caffeine products and to raise their awareness.

However, an official at the ministry said there is no legal basis for regulating the sale of coffee to adolescents in cafes near schools or private education institutions.