Sixteen-year-olds who watch a lot of television and do not exercise are at an increased risk of developing metabolic syndrome at the age of 43, a new study has found.

Metabolic syndrome refers to a group of conditions including obesity, high blood pressure and abnormal cholesterol levels, which combine to increase the risk of heart disease, stroke and diabetes. Having just one of these conditions increases your risk of a serious disease. However in metabolic syndrome, when all the conditions are present together, the risk is even greater.

Swedish scientists monitored the progress of almost 900 people from 1981, when they were around 15 and 16 years old, until 2008.

While it has previously been shown that a lack of exercise and leading a sedentary lifestyle increases the risk of metabolic syndrome, this study shows that the risk extends over a large period of time, specifically between the ages of 16 and 43.

"The results demonstrate that we need to consider how we can reduce sedentary lifestyle among children and adolescents. It may be more important than only focusing on increased fitness and sports activities for those who are already interested," the team from Umeå University said.

Details of these findings are published in the journal, Diabetes Care.