Both loneliness and social isolation are linked with an early death risk for older individuals, a new study found. However, reducing social isolation might decrease death rates in this age group, researchers said.

Social isolation is when a person has very few social contacts and limited interaction with others, while loneliness is when a person feels disconnected from the rest of the society. "Someone who's socially isolated is likely to be lonely, and vice versa, but that's not completely the case," said epidemiologist and lead author Andrew Steptoe of University College London, reports Science.

A related study in the journal Archives of Internal Medicine had said that a person's level of loneliness may predict the chances of him/her getting serious health complications in the future.

"Social contact is a fundamental aspect of human existence. The scientific evidence is that being socially isolated is probably bad for your health, and may lead to the development of serious illness and a reduced life span," said Steptoe, according to HealthDay.

The present study included data from 6,500 men and women aged 52 or older who were enrolled in the English Longitudinal Study of Ageing in 2004-2005. The study participants were then asked to complete a questionnaire that checked their level of loneliness and social isolation.

Researchers found that socially isolated people had a 26 percent higher risk of dying early than others. The risk remained even after the researchers accounted for other factors like age, sex , health and education - all of which are known to contribute to early death risk.

It isn't that all socially isolated people are bound to be unhappy and feel lonely. However, elderly people with more social connections have other people around them who can take care of their health.

"There are plenty of people who are socially isolated but who are perfectly happy with that," Steptoe said, reports Science. "But even then we should be trying to make sure there's enough contacts with them so that if something does go wrong ... they're going to be advised and supported."

The study is published in the journal Proceedings of the National Academy of Sciences.