Teenagers who drink too much caffeine could be affecting their brain development, Swiss scientists have warned.

Children and young adults guzzling the equivalent of three cups of coffee – three cans of energy drink or approximately one large bottle of cola – could be unconsciously reducing the amount of deep sleep they enjoy and slowing their brain development.

Humans and other mammals display particularly intensive sleeping patterns during puberty and their brains mature fastest at this time.

However, scientists exploring the effects of caffeine on rats found the maturing processes in the rodents’ brains were delayed.

The study was supported by the Swiss National Science Foundation (SNSF) which is concerned that children and young adults’ caffeine consumption has soared by over 70 per cent during the past 30 years.

The foundation said children’s exposure to caffeine will only grow as the drinks industry is posting its its fastest-growing sales in the segment of caffeine-laden energy drinks, causing some scientists to worry about possible health risks caused in young coffee-addicts and soft drink fans.

Researchers at the University Children’s Hospital Zurich, found that in pubescent rats, caffeine intake equating to three to four cups of coffee per day in humans results in reduced deep sleep and a delayed brain development.

In rats and humans, the duration and intensity of deep sleep as well as the number of synapses or connections in the brain increase during childhood, reaching their highest level during puberty and dropping again in adult age.

Reto Huber, who led the research, said: ‘The brain of children is extremely plastic due to the many connections’ and when the brain begins to mature during puberty, a large number of these connections are lost.

‘This optimisation presumably occurs during deep sleep. Key synapses extend, others are reduced; this makes the network more efficient and the brain more powerful,’ he said.

The scientists administered moderate quantities of caffeine to 30-day-old rats over five days and measured the electrical current generated by their brains.

The deep sleep periods, which are characterised by slow waves, were reduced from day 31 until day 42, well beyond the end of administering caffeine.

Compared to the rats being given pure drinking water, the researchers found far more neural connections in the brains of the caffeine-drinking animals at the end of the study.

The slower maturing process in the brain also had an impact on behaviour.

Rats normally become more curious with age, but the rats consuming caffeine remained timid and cautious.

Professor Reto believes more research should be done to explore the brain’s maturing phase in puberty, when many mental diseases can break out.

If the rat brain differs significantly from humans’, the many parallels in how the brain develops raises the question of whether children’s caffeine intake is harmless, the scientists said.

source: Dailymail UK