Vacation

Vacation time can undo a lot of mental stress. (Philip and Karen Smith / Getty Images)

Got stress?

If you answered no, hooray for you! (And, by the way, what planet are you from?)

But if you answered yes (like any normal member of the human race), you're likely heartened by the arrival of vacation season. Just the ticket for a little stress-reduction.

And that can have some big payoffs. It can lower your blood pressure, boost your immune system and help you live longer. It may even make you smarter.

"A vacation is not a luxury," says Jens Pruessner, an associate professor in the departments of psychology, psychiatry, neurology and neurosurgery at McGill University in Montreal. "It's an investment in your health."

Most of what scientists know about the brain and chronic stress comes from studies of rodents, whose response systems are very much like ours (perhaps disconcertingly so) and who therefore make good stand-ins for us. But rodents rarely pack their bags and head for the beach when summer rolls around, so it's harder to use them as models for vacationers.

Nonetheless, researchers have learned enough to make some useful suggestions:

Plan ahead

A vacation is a chance to get away from many of the stresses you can't get away from in your everyday life (your boss, your commute, the chaos that is your home). Of course, it can also introduce new ones. But while some of these may be out of your control — bad directions, missed connections, loud neighbors in hotels with thin walls — planning ahead can forestall others. If it's stressful for you to be around your in-laws, don't arrange a monthlong camping trip with them. If you're afraid of airplanes, pick a destination you can drive to instead — and don't get talked into skydiving lessons. If you suffer from separation anxiety, don't go anywhere Spot can't go too.

Making your vacation as stress-free as possible pays off, according to a 2010 study in the Netherlands. When researchers looked at how happy people were after taking vacations, only those who felt very relaxed while they were away were happier than people who hadn't taken a trip at all.

But the same study found that people who were busy planning a vacation were happier than those who had no vacation to plan — so even when a vacation turned out to be a dud, the time spent planning it may have made it all worthwhile.

One caveat: For some people, going on vacation may be more stressful than not going — perhaps because of money concerns or because they're just not comfortable being away from home or from work. In such cases, it may be that no amount of planning can make a vacation a good idea.

Make sure it's fun

This is not exactly shocking news, but it is nice to know for a scientific fact that fun is good for you (and your brain). A study published last year in the Proceedings of the National Academy of Sciences found exactly that. In rats, anyway.

"It doesn't get rid of stress, just lowers it, across all aspects of the hormonal system," says study co-author James Herman, director of the Laboratory of Stress Neurobiology and professor of psychiatry and behavioral neuroscience at the University of Cincinnati.

Rats in the study had access to a sugar solution twice a day for two weeks. Then researchers tested their responses to stress by placing them in tubes that restricted their movements. Compared with controls, the rats who had had access to sugar had lower heart rates and levels of stress hormones. Other rats who received a saccharin-sweetened solution also had reduced stress responses, but rats who had sugar delivered directly to their stomachs did not. Researchers inferred that it was the pleasurable taste, not the calories in the solution, that produced the effect.

To confirm the pleasurability hypothesis — and to show that it held for more than just taste — other rats were allowed daily visits with "pliant females" for two weeks, Herman says, and they too showed the same stress reductions.

To travel or not?

Even if you love to travel, at times the hairy logistics can present you with plenty of opportunities to blow your cool. On the other hand, a situation is only stressful if you perceive it to be. "A lot depends on your appraisal of the evidence," says Carlos Grijalva, a professor of psychology and behavioral neuroscience at UCLA. "How you evaluate the situation is critical."