There are any number of ways to measure quality of life across geographic areas: Who has the longest commutes? Who breathes the cleanest air? Where are obesity rates lowest? Who has the most access to exercise facilities?

The Robert Wood Johnson Foundation has the answers. The foundation’s annual County Health Rankings, a joint project with the University of Wisconsin Population Health Institute, use nearly three dozen indicators to pit regions against each other, all in an effort to measure ways to improve health outcomes across the country.

The rankings, released Wednesday, show the counties where residents enjoy higher-than-average health have better access to healthy foods, parks and exercise facilities, where doctors are plentiful and the air is cleaner. Unhealthy atmospheres can lead to lower-than-average graduation rates, higher obesity and denser, more expensive housing conditions (Find the complete report, along with downloadable data, here).

Out of those 30-plus criteria, here are the 10 maps that best illustrate where Americans are healthiest, and why:

The healthiest air is found mostly in California and southern Oregon. The least healthy air, with particulate rates more than twice that of the healthiest counties, is found in rural Tennessee and Kentucky.

Counties with the lowest air particulate matter

State County Average daily PM25
California Sonoma 7.2
California Lake 7.2
California Monterey 7.2
California Santa Barbara 7.2
California Mendocino 7.3
California San Luis Obispo 7.5
California Marin 7.5
California Colusa 7.6
California Napa 7.6
California Orange 7.6

Counties with the highest air particulate matter

State County Average daily PM25
Tennessee Williamson 14.5
Tennessee Cheatham 14.6
Kentucky Trigg 14.6
Tennessee Montgomery 14.6
Tennessee Hickman 14.6
Tennessee Dickson 14.7
Tennessee Stewart 14.7
Tennessee Benton 14.8
Tennessee Houston 14.8
Tennessee Humphreys 14.9

Fewer Middle Americans tend to report fair or poor health than those in other states. Just 4 percent of Blaine County, Neb., residents described themselves as in fair or poor health, the lowest rate in the country. On the other end of the spectrum, more than half of those in Hickory County, Mo., and Limestone Co., Texas, said their health was fair or poor (A word of caution: Almost 400 counties didn’t submit enough data to be ranked).

Counties reporting the lowest percentage of fair/poor health

State County Pct fair/poor health
Nebraska Blaine 4
Kansas Cheyenne 5
Iowa Mitchell 5
Kansas Smith 5
South Dakota Clay 5
Utah Morgan 5
Iowa Cedar 5
Iowa Winneshiek 5
North Dakota Griggs 5
Ohio Geauga 6

Counties reporting the highest percentage of fair/poor health

State County Pct fair/poor health
Kentucky Floyd 38
North Carolina Greene 38
Kentucky Owsley 38
Alabama Chambers 39
Kentucky Magoffin 39
Missouri Dent 39
Kentucky McCreary 41
Tennessee Scott 46
Texas Limestone 50
Missouri Hickory 51

The highest rates of obesity are found in the South, while the lowest obesity rates occur almost exclusively in the Mountain West. The lone exceptions: Marin County, Calif., and Manhattan.

Counties reporting lowest obesity rates

State County Obesity rate
Wyoming Teton 13
Colorado Eagle 13
Colorado Routt 13
New Mexico Santa Fe 14
Colorado Pitkin 14
Colorado Summit 15
Colorado Boulder 15
Utah Summit 15
California Marin 15
New York New York 16

Counties reporting highest obesity rates

State County Obesity rate
Mississippi Wilkinson 42
South Carolina Williamsburg 43
Mississippi Noxubee 44
Alabama Lowndes 44
Mississippi Sunflower 44
North Dakota Sioux 44
South Dakota Ziebach 45
Mississippi Jefferson 45
Mississippi Coahoma 47
Alabama Greene 48

Not surprisingly, the counties with ample access to exercise facilities are less likely to end up high on the obesity list, while more rural counties lack sufficient exercise options. Twenty counties, ranging from rural Georgia, Texas, South Carolina, North Dakota, Kentucky and Oklahoma, have no exercise facilities. Fifty-one counties in states all over the country — though mostly in urban areas — have enough facilities to give everyone access.

Highly-educated, wealthier counties, ranging from the Washington suburbs of Falls Church City and Loudon County, Va., to Los Alamos, N.M., have the lowest number of children in poverty. Southern rural counties, mainly in Mississippi, have the highest percentages. In the most extreme case, children in Dallas County, Ala., are 20 times more likely to be impoverished than children in Falls Church City.

Counties with the lowest child poverty percentages

State County Pct of children in poverty
Virginia Falls Church City 3
New Mexico Los Alamos 4
Colorado Douglas 4
Virginia Loudoun 4
New Jersey Hunterdon 5
Minnesota Carver 5
New Jersey Morris 5
Illinois Monroe 6
Indiana Hamilton 6
South Dakota Lincoln 6

Counties with the highest child poverty percentages

State County Pct of children in poverty
Mississippi Leflore 55
Mississippi Quitman 55
Mississippi Washington 55
Mississippi Holmes 56
Mississippi Humphreys 57
Kentucky Owsley 57
Mississippi Sharkey 58
Mississippi Sunflower 58
Louisiana Madison 59
Alabama Dallas 60

High poverty, bad air and high obesity rates translate to premature deaths. The National Center for Health Statistics measures what it calls the years of potential life lost — the years before age 75 that residents pass away. Again, Southern states are more likely to have higher YPLL numbers. But the most extreme outliers are all in rural counties in North and South Dakota.

Lowest years of potential life lost

State County YPLL
Nebraska Polk 2950
Texas Presidio 3136
Virginia Loudoun 3290
Colorado Eagle 3517
Minnesota Yellow Medicine 3536
South Dakota Lincoln 3588
North Dakota Dickey 3592
Virginia Fairfax 3617
Colorado Douglas 3622
New Jersey Somerset 3680

Highest years of potential life lost

State County YPLL
Mississippi Quitman 17823
Alaska Wade Hampton 18391
Georgia Clay 19240
Montana Roosevelt 19937
North Dakota Benson 20202
South Dakota Todd 20965
South Dakota Corson 21217
South Dakota Buffalo 23312
South Dakota Shannon 23851
North Dakota Sioux 24668

A healthy life begins at birth, and counties in the Mountain West and Great Plains states registered the lowest number of low-weight babies — which the National Center for Health Statistics defines as live births less than 2,500 grams. Much higher percentages of underweight babies are born in Southern states, with Georgia and Mississippi dominating the bottom 10.

Counties with lowest low-birthweight percentages

State County Pct LBW
Idaho Boundary 2.9
Nebraska Cedar 3.3
Washington San Juan 3.8
Minnesota Lac qui Parle 4.0
Iowa Davis 4.1
Iowa Jefferson 4.1
Iowa Osceola 4.2
Alaska Valdez-Cordova 4.2
South Dakota Hamlin 4.3
Minnesota Wilkin 4.3

Counties with highest low-birthweight percentages

State County Pct LBW
Alabama Greene 16.0
Mississippi Issaquena 16.0
Georgia Randolph 16.1
Georgia Talbot 16.3
Mississippi Tallahatchie 16.3
Mississippi Claiborne 16.8
Mississippi Jefferson 16.8
Georgia Terrell 17.0
Georgia Webster 17.1
Mississippi Coahoma 17.6

Here’s one area where broad regional differences are muted, but where racial divides become clear: The counties with the lowest percentages of 9th graders who graduate from high school in four years are, broadly speaking, counties with heavy Native American populations, which are experiencing a drop-out crisis far worse than the rest of the country. Four counties, three of them in Oklahoma, graduated all of their 9th graders in four years, though only one county that graduated more than 95 percent of its 9th graders had sample sizes larger than 1,000.

Counties with the highest 4-year graduation rates for 9th graders

State County Graduation rate
Tennessee Stewart 98
Tennessee Trousdale 98
Texas Titus 98
Texas Kendall 98
Texas Chambers 99
Kentucky Livingston 99
Idaho Madison 100
Oklahoma Dewey 100
Oklahoma McClain 100
Oklahoma Cimarron 100

Counties with the lowest 4-year graduation rates for 9th graders

State County Graduation rate
Colorado Sedgwick 17
Idaho Butte 24
Kansas Kiowa 26
Oklahoma Osage 27
South Dakota Shannon 29
Georgia Union 37
Florida Jefferson 38
Alaska Bethel 41
Georgia Crawford 43
South Dakota Todd 43

Boroughs of Alaska experience a higher instance of sexually transmitted disease cases than other counties, as measured by the number of chlamydia infections per 100,000 people. Infection rates in low-population Alaska boroughs is nearly 1,000 times higher than in smaller rural counties in states like Indiana, Utah and Minnesota.

Lowest STD rate per 100,000 residents

State County STD rate
Indiana Pulaski 37
California Mariposa 39
Indiana Brown 40
Utah Morgan 41
Minnesota Marshall 42
Kentucky Morgan 43
Minnesota Meeker 43
Wisconsin Vernon 43
Nebraska Cedar 46
Idaho Madison 48

Highest STD rate per 100,000 residents

State County STD rate
Mississippi Tunica 1,797
Virginia Petersburg City 1,859
South Dakota Todd 1,884
South Dakota Shannon 1,989
South Dakota Corson 2,014
Alaska Nome 2,131
South Dakota Dewey 2,140
Alaska Bethel 2,222
Alaska Wade Hampton 2,702
Alaska Northwest Arctic 2,754

There are less obvious indications of good qualities of life too, like proximity to work. The study’s authors point out that longer commutes equate to more stress, which means lower quality of life for the percentage of drivers who commute 30 minutes or longer by themselves every day. That’s good news for residents of Alaska’s more far-flung boroughs — there aren’t enough roads to drive more than 30 minutes to work — and bad news for exurban and rural residents who commute in to cities.

Counties with the largest percentage of long-commute drivers

State County Long commute drivers
Kentucky Spencer 63
Georgia Paulding 64
Texas San Jacinto 64
Maryland Charles 64
Virginia Charles City 65
Kentucky Robertson 66
Virginia Amelia 66
North Carolina Gates 66
Colorado Park 67
Colorado Elbert 71

Counties with the lowest percentage of long-commute drivers

State County Long commute drivers
Alaska Aleutians West 0
Alaska Lake and Peninsula 0
Alaska Nome 0
Alaska North Slope 1
Alaska Yakutat 1
Alaska Wrangell-Petersburg 1
Massachusetts Nantucket 1
Alaska Bristol Bay 1
Alaska Dillingham 1
Alaska Aleutians East 2
Alaska Kodiak Island 2
Alaska Northwest Arctic 2
Alaska Skagway-Hoonah-Angoon 2