If you want to live long and prosper, step one is to make sure you "live long."

But now, stunning new research presented by a neuroscientist at the American Association for the Advancement of Science suggests there could be four other key habits that make it much more likely you'll live past 90.

The research was led by Claudia Kawas of the University of California, Irvine, where she's the Nichols chair in clinical neuroscience and a professor of neurobiology and behavior and neurology.

For the past 15 years, Kawas and her team have been examining the health and habits of 1,700 people over the age of 90, to determine what makes it more likely that people will live to that age.

The cohort is called simply the 90+ Study, and it's ongoing (details below if you know someone over 90 who might want to join).

Here are the key findings Kawas presented. Two of them are especially surprising. 

They drank alcohol.

Participants in the 90+ Study who consumed the equivalent of two glasses of beer or wine per day were 18 percent less likely to experience premature death. (More on this one below.)

They were slightly overweight.

Those who were a bit overweight during their 70s (but not obese) were 3 percent less likely to experience premature death.

They had hobbies.

This one is a bit less surprising, but had the biggest percentage impact: Participants who devoted two or more hours a day to hobbies were 21 percent less likely to die early.

They had some physical activity.

Specifically, engaging in physical activity such as walking for 15 to 45 minutes each day reduced the likelihood of an early death by 11 percent.

Unfortunately, although perhaps not unexpectedly, about 40 percent of people over 90 suffer from dementia, according to the study, and 80 percent have some kind of disability.

We should spend a little bit of extra time on what's probably the most surprising finding: the one that suggests drinking alcohol improves longevity.

The thing to keep in mind here is that it's moderate alcohol use that appeared to have a positive outcome on life expectancy--just a couple of glasses a day. 

"I have no explanation for it, but I do firmly believe that modest drinking improves longevity," Kawas was quoted as saying by the British newspaper The Independent.

By the way, if you or someone you know is approaching 90 years or is that age or older, the 90+ Study is looking for more participants.

Requirements: You must be able to participate in two annual visits with researchers, and be willing to donate your brain to research after death. You can call (949) 768-3635 in the United States or email study90@uci.edu for more information.