The health problems that often plague athletes are well-known, but what about the zealous followers who watch them play? Aside from the risks associated with dashed hopes and happy dances, is there much to be concerned about? In fact, there is. Researchers have been taking a look at what happens to sports fans who are emotionally invested in the outcome of a big game, and while there can be positive benefits of being a fanatic for your team, at times, even being a fan can be treacherous.

1. Heart attacks

Because of the connection between emotions and cardiac health, heart-related deaths can rise or fall in a region depending on how the local teams fare. In 2009, when the Pittsburgh Steelers beat Arizona in the Super Bowl, for example, Pittsburgh-area doctors noticed 25 percent fewer circulatory heart-related deaths than average over the following eight days, according to Robert Kloner, a cardiology professor at the University of Southern California who talked to the Wall Street Journal.

However, there's a flip side. When the New York Giants beat the Patriots in the 2008 Super Bowl, the number of circulatory heart-related deaths in Massachusetts shot up 20 percent during the next eight days. Kloner notes that people don’t need to give up sports altogether to reduce the post-game heart attack risk, but ardent sports fans should be aware of stressful emotional situations and should avoid getting too worked up in the period following a big loss.

2. Car accidents

A North Carolina State University researcher discovered that there was an increase in auto-related deaths in cities where the local college and pro football and basketball teams had just won by a close margin. (And that's even after factoring in drunk driving, since studies show that as many as 8 percent of attendees are legally drunk after a game.)

The North Carolina study found that the more competitive the game, the more auto deaths to occur. They devised a "closeness scale" from one to five, and for each point the game increased on the scale, there was an average 21.2 percent increase in traffic deaths, and a whopping 133 percent increase from one to five. For every four close games, there is an additional death near the game location, one of the researchers said, and increased testosterone may be to blame.

3. More susceptible to advertising

A close game also has another unexpected effect: it tends to give advertising a stronger impact. Ads that fans see after the end of a very competitive game tend to resonate with fans more than ads aired during a less-exciting game, says Colleen Bee from Oregon State University.

“Games with high excitement levels result in a transfer of that emotion to the ads — particularly to ads shown at the end of the game that also have a lot of energy and excitement built in,” said Bee. The study found that fans who were excited after a nail-biter of a game rated ads more favorably than the ads watched after a boring game. Which isn’t much of a health risk, per se, as long as the viewer can fight off the temptation of ads promoting excessive beer and junk food.

4. Despondency

When your team loses, often times depression may follow. "Loss is one of the most psychologically disappointing experiences that a person can have," says sports psychologist Ian Birky, director of counseling and psychological services at Lehigh University in Bethlehem, Pa. But unless the blues last for more than a few days, it’s probably nothing to worry bout. Moping about for longer, however, may suggest a need for professional help.

5. Raised stress hormones

In a study published in 2012, Leander van der Meij from VU University Amsterdam measured hormone levels in saliva samples taken from 58 soccer fans in Spain during the 2010 World Cup. All those participating were fans of Spain's team, and even though Spain took home the cup, all participants had elevated levels of cortisol, a hormone associated with stress, and testosterone.

"The people who identified most strongly as fans released the most cortisol and were the most stressed, partly because they had no actual control," says van der Meij. And while overexposure to cortisol and other stress hormones can disrupt your body's processes, another study that measured increases in testosterone after a win noted that it can also lead to increased libido and more energy — not necessarily a bad thing.

6. Junk food binges

A loss by a favorite team can lead to a loss of self-control, says Yann Cornil and Pierre Chandon in a study published in Psychological Science. And that often manifests in a junk food binge. In the study, the researchers examined data from NFL fans and found that consumption of saturated fat spiked by 16 percent for fans whose favorite team lost. Yet the converse is true as well. After a win, fat consumption went down by 9 percent and overall calorie consumption dropped by 5 percent.

"There's research showing that when something good happens to your life, you're more future-oriented," says Cornil. "So if you have good news and you feel good about yourself, you want to keep feeling good about yourself; you have an increased motivation to follow your diet, exercise, to go to the gym." Feeling bad elevates short-term goals like craving comfort food. But even if you adore a perennially losing team, there's help. "If you are concerned about healthy eating: After a defeat, write down what is really important to you in life,” Cornil and Chandon suggest. “In our studies, this simple technique, called ‘self affirmation,’ completely eliminated the effects of defeats.”

Despite the risks, it doesn't mean sports should be off-limits. The New York Times reminds us that in most cases, sports fandom can be healthy. Studies find that an attachment to a team can protect people from depression and do wonders for fostering feelings of self-worth and belonging. Just try not to freak out too much, remember to drive safely, and don't drown your sorrow in chili-cheese fries.

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