Being lonely is not good for the health and now researchers say it is a factor in raised blood pressure.

It has now joined the ranks of obesity and lack of exercise as a potential risk factor for hypertension.

According to new research loneliness can up a blood pressure reading for adults over the age of 50 by as much as 30 points.

Lead researcher Louise Hawkley, a senior research scientist at the Center for Cognitive and Social Neuroscience at the University of Chicago says the results have come as a surprise to all as the message is that being lonely is a health risk, and the lonelier you are, the higher your blood pressure.

High blood pressure says Hawkley, has all kinds of negative consequences.

The list of studies pointing to the deadly impact of loneliness, particularly on senior citizens is growing.

This latest study says loneliness is a major risk factor in increasing blood pressure in older Americans and could increase the risk of death and stroke or heart disease.

This study involved people between the ages of 50 and 68, but the problem increases with the years, which indicates it is more severe for senior citizens age 70 and older.

A study last year found nearly 60 percent of the elderly in this group are experiencing some form of loneliness.

The latest study was apparently prompted by previous work in 2002, that discovered profound and lingering effects of loneliness on the blood pressure of undergraduate college students.

Hawkley’s team interviewed 229 people aged 50 to 68 years of age, using standard questionnaires to determine each participant’s perceived level of loneliness, as well as other psychosocial and cardiovascular risk factors.

The researchers found that lonely older people had blood pressure readings that were as much as 30 points higher than others, even after other negative emotive states, such as sadness, stress or hostility, were taken into account.

This effect appeared to get stronger with age, say the team, but may not be that simple to resolve for a range of reasons.

Hawkley suggests targeted interventions that break that cycle might help change things; she believes loneliness, like obesity and other cardiovascular risk factors, may be on the rise in America.

Richard Suzman, Ph.D., director of the Behavioral and Social Research Program at the National Institute on Aging (NIA), says the findings need to be replicated before any firm conclusions can be drawn, but should the findings remain consistent, new interventions to change, modulate or reduce the impact of loneliness on blood pressure will be needed.

If such interventions are low-cost and practical, says Suzman, they will have a significant public health impact.

The research is published in the upcoming issue of Psychology and Aging.