Social networks and health:communicable but not infectious

Harvard men ' s Health Watch

Poet and pastor John Donne famously proclaimed "No Man is a island." It is true in the He day, and because society have become increasingly complex and interdependent over the ensuing years, It ' s certainly true today. Studies in the modern era show, people can be good medicine and, individuals with strong social supports is Healt Hier than those who is lonely and isolated. Married men, for example, is healthier than their single, divorced, or widowed peers.

It's easy-to-understand how face-to-face interactions can is beneficial. But the suggests that social interactions has a ripple effect that extends far beyond household and family units. Some of these effects can promote health; Others is detrimental. But whether for good or ill, these communitywide effects give networking a new meaning.

Spreading problems

Obesity is a enormous health issue in the U.S. Since of every three Americans are overweight or obese, it's no stretch to say the problem have assumed epidemic Propor tions. There is many explanations for we expanding waistlines, starting with insufficient amounts of exercise and excessively l Arge portions of inexpensive, calorie-dense prepared and processed foods. But was it possible that social interactions also play a role, and that the obesity epidemic was in part a contagious diseas E? An important study suggests this answer is yes.

Researchers from Harvard and the University of California investigated 12,067 people who had been evaluated medically O N multiple occasions from 1971 to 2003 as part of the Framingham heart Study. They found that if one sibling became obese during the study and the chance that another sibling would become obese increased by 40%. Genetics might account for some of the parallel weight gain in siblings, and not for the fact if a spouse became OBEs E, the likelihood, the other spouse would follow suit jumped by 37%. Shared meals and other lifestyle habits might explain so link, but the scientists also found so if a person had a frie nd who became obese, his chance of growing obese rose by 57%.

The impact of networks depended more on social status than physical proximity; Obesity in a neighbor had much less infl Uence than obesity in a friend, regardless of what far away the friend lived. Friends of the same sex were particularly influential; A man had a male friend who became obese experienced a 100% increase in his own chance of becoming obese. And when both people regarded their friendship as mutual, obesity in one member of the pair increased the other ' s Likelihoo D of becoming obese by a staggering 171%.

Why does obesity spread in social networks? The effect extends far beyond the impact of genetics and GKFX environmental influences. The researchers didn't specifically investigate diet and exercise patterns, but they do find that changes in smoking did The spread of obesity in the Framingham network. Although scientists don ' t fully understand how obesity spreads, they suspect a major factor was that a social network influ Ences what it members perceive as normal and acceptable. If A man sees him friends become obese over time, he may accept weight gain as natural, even inevitable. Instead of exercising more or eating less if his own weight begins to creep up, he may simply go with the flow and join The crowd.

The notion that obesity are contagious may lend new weight to folks who claim "do me sick." But the same researchers who revealed the spread of obesity also tell us that networks can spread positive emotions as wel L.

Spreading happiness

Like the study of obesity, the Framingham heart Study ' s database was the foundation of the Happiness study. 4,739 people who were tracked between 1983 and 2003 served as the primary study population. Together, these subjects reported a total of 53,228 social ties to family, friends, neighbors, and coworkers. Because scientists has kept a close eye on the Framingham volunteers since 1971-over three generations-detailed medic Al and psychological information was available for many of these people.

The researchers used the Center for epidemiological studies Depression scale to evaluate happiness at the start of the Stu Dy and at subsequent follow-up examinations. Just as the obesity study provided information on what weight changed over time, the happiness study focused on changes in Mood over time.

The Framingham study confirmed earlier findings that the strongest determinant of whether a person would be happy in the FU Ture is what happy he has been in the past. And the study also confirmed that healthy people tend to being happier than those who is ill; Men tend to be a bit happier than women; And more educated people tend to being slightly happier than those with less schooling.

Previous had validated the everyday observation that emotions is contagious over a very brief time frame; If one person in a class starts to laugh or cry, others often follow suit, and the effect wears off in minutes. But the Framingham study added a unexpected finding:happiness can also spread more diversely and broadly across social N Etworks.

The scientists found that if one spouse became happy, the likelihood and the other spouse would become happy increased by 8%. Siblings who became happy increased the other sibling ' s chance of becoming happy by 14%. But while the spread of obesity is not related to physical closeness, the spread of happiness do depend on distance. Spouses and friends only transmitted happiness to people living within a mile, and although obesity do not spread between Neighbors, happiness did. But physical proximity on the job does not allow happiness to spread among coworkers.

Like obesity, happiness spread more readily between members of the same sex than between people of the opposite sex. Like obesity, the spread of happiness seemed to reach across in least three degrees of separation, spreading, for example, From a friend to the friend of a friend and then to the friend of this friend. But the impact diminishes with all degree of separation, and even within first-degree contacts, it begins to wane after s IX to 12 months.

Although the researchers did not discover exactly how happiness spreads across social networks, they do speculate on t He positive role that spreading happiness may play. Humans is social beings, and the health and well-being of one person influences others. Since happiness and optimism is linked to better health and improved longevity, contagious happiness might has a benefic Ial effect on the health of an entire community. Interestingly, the Framingham study found that unhappiness does not spread across social networks. If emotions were the flu, that would mean that immunity could spread, but the virus itself could not-it ' s a fantasy for The flu season that's just kicking off, but it's a real possibility for the IT emotions spread.

Malignant loneliness Social isolation is a well-established heart attack risk factor and while strong Interperson Al ties and community activities appear protective. Although studies show that marriage appears to improve the prognosis of prostate cancer, it's not clear that social Isolat Ion is a cancer risk factor. A study from the University of Chicago suggests, the isolation may has that effect-at least in female rats. As compared to animals who were allowed to live in groups of five, rats that were raised in isolation had a threefold incr Ease in the risk of breast cancer, and their tumors were much more aggressive than the cancers this developed in the Commu Nity dwellers. Changes in sex hormones didn't appear to account for the difference, but excessive stress was a likely explanation.< /p> Females is more gregarious than males, and the men is not rats. Still, the animal experiment raises interesting questions for future Human research.

A New Science

Epidemics has plagued humans throughout history. Before scientists identified the microbes responsible for a epidemic as well as the the-the-germs-spread from-person to P Erson, people blamed things like human misbehavior, divine intervention, and supernatural forces for epidemics ranging fro M The Black death of the middle Ages to the Spanish Flu of 1918. Doctors understand the infections spread through communities, they can use tools such as immunization, HY Giene, and the isolation of sick individuals to control epidemics.

Social-network Science was much newer than epidemiology, and its eventual impact on medicine remains uncertain. The statistical methodology used in the Framingham, the obesity and happiness have come under fire. Still, the studies raise the intriguing possibility that noninfectious phenomena can spread across communities through SOC Ial networks, and researchers has added alcohol consumption and depression to the list of things. Social networks.

Natural social networks may already has a substantial impact on health, and if doctors learn to harness them to spread he Althful habits, positive attitudes, and wise lifestyle choices through communities, they may is able to improve public hea Lth. It might sound farfetched, but the support groups such as Alcoholics Anonymous and Weight watchers already function as small, Artificial therapeutic networks.

More about is needed. Call it a network in progress.

Social networks and health:communicable but not infectious