Excessive internet browsing can lead to negative outcomes like social isolation, depression, insomnia and obesity, especially among teenagers, a study by industry chamber Assocham has said.

The study defined over five hours of internet usage daily as "excessive".

It said teenagers (in the age group of 12-18 years) are most vulnerable to these risks due to over usage of internet.

"A large number of children and adolescents have access to internet and are getting exposed to the online world at a very early age," Assocham Secretary General D S Rawat said in a statement.

The survey said that working parents' children are more internet addictive in the absence of parental supervision compared to those whose single parent is employed.

"This trend is emerging mostly in metros where normally both the parents are employed," it said.

The chamber surveyed 1,500 internet users, both boys and girls, in 10 major cities including Delhi, Mumbai, Kolkata, Chennai, Pune and Bangalore.

"Boys reported excessive internet browsing compared to girls," the study said.

Of the total respondents surveyed, over half of them said that they accessed internet for over five hours a day, about a quarter of them told they browse for less than five hours daily and the remaining said they did not access internet everyday, it said.

The study said with the availability of broadband facility at cheap rates, internet has become more accessible in homes, schools, colleges, libraries and internet cafes.

"Also, the introduction of 3G services has further increased the accessibility of internet through mobile phones," it said.

The survey said excessive internet usage is also due to less likelihood of having friends and feelings of depression.