Rates of smoking and obesity are low, so the metro area has low mortality from heart disease and low rates of hypertension.
Because traffic congestion is a serious problem in the city, many locals use the region's excellent subway system or walk or bicycle to work.
In 2011, Boston was ranked the fifth most literate big city in the United States, and a high share of area residents have a college degree.
San Francisco State University has an Osher Lifelong Learning Institute.
The University of California, San Francisco, is exclusively devoted to health and medical education, which contributes to a high number of physicians per capita.
Boston's coastal location means it does get severe storms, including nor'easters, blizzards and the occasional hurricane.
That's when it's time to curl up on the couch with that special someone and watch the weather roll in.
Baltimore doesn't make a lot of top 10 lists, overshadowed as it is by the powerhouses of the Northeast Corridor.
But once you experience the easy pace, historic neighborhoods and waterfront establishments, you'll get Baltimore's nickname: Charm City.
For older singles, the inclusiveness is evident in the corner pubs, the walkable streets of Federal Hill, Charles Village and Fells Point, and the lively Cross Street Market.
Baltimore is a city of natives, a place with a sense of community that spans generations.
The job market is holding up better than it is in most cities, and foreclosures are much less of a problem than they are elsewhere in California.
Maybe it is the mix of nature's wonders and cosmopolitan allure that sparks romance: Whether you are strolling the wharfs, huffing up one of the city's vertiginous hills, sampling sushi in the Noe Valley neighborhood or cycling across the Golden Gate Bridge, San Francisco seems to shine — at least when it's not blanketed in fog.
The city has a diverse and tolerant population, with a strong gay and lesbian community and more than 100 distinct neighborhoods. In 2010, Foreign Policy magazine ranked San Francisco as the world's 12th most important city.