ZIP code
50138
in Knoxville, IowaPopulation 11,117
54.24/ 100
Ranked #10,392 of 32,066 US ZIPs (top 32%)
Ranked #314 of 922 Iowa ZIPs (top 34%)
Ranks are modeled estimates — ZIPs a few hundred places apart are effectively tied.
What defines this ZIP
Metrics where this ZIP sits in the tails of the national distribution — the ones that most set it apart. Select any tile for its definition and methodology.
Radon
3.9 pCi/L
in the top 2.3% nationally
Lower is healthier
ST73rdUS98thDefinition & source ›
The modeled typical indoor radon level for this area, in picocuries per liter — the EPA recommends fixing a home at 4 pCi/L or above.
Modeled from indoor-radon measurements. In Alaska and Hawaii, where those measurements are not published, a US Geological Survey geologic radon-potential category stands in — a coarser input, disclosed rather than hidden.
Full methodology ›Lithium in drinking water
130 µg/L
in the top 1.7% nationally
Lower is healthier
ST92ndUS98thDefinition & source ›
The average detected level of lithium — a natural trace metal with no federal drinking-water limit yet — across the public water systems serving this ZIP, in micrograms per liter.
Measured from EPA records for the public water systems that serve this ZIP. Households on private wells — roughly 30% of the US population — are not covered by this measure, and this figure says nothing about their water.
Full methodology ›Mental-health provider access
0.17 per 1,000 residents
in the top 5.5% nationally
Higher is healthier
ST94thUS95thDefinition & source ›
The number of mental-health clinics located inside this ZIP’s boundary, per 1,000 residents.
Counted from establishments located inside this ZIP’s boundary, so one just across the line is not counted. Where a ZIP has too few residents for the density to be reliable, no value is published rather than an unreliable one.
Full methodology ›Short sleep
29.1%
in the bottom 6.2% nationally
Lower is healthier
ST8thUS6thDefinition & source ›
The estimated share of adults who usually sleep less than seven hours in a 24-hour period.
Full methodology ›Binge drinking
19.8%
in the top 7.0% nationally
Lower is healthier
ST52ndUS93rdDefinition & source ›
The estimated share of adults who report binge drinking — five or more drinks on one occasion for men, four or more for women.
Full methodology ›Civic-institution access
0.69 per 1,000 residents
in the top 7.8% nationally
Higher is healthier
ST88thUS92ndDefinition & source ›
The number of civic and social organizations inside this ZIP’s boundary, per 1,000 residents.
Counted from establishments located inside this ZIP’s boundary, so one just across the line is not counted. Where a ZIP has too few residents for the density to be reliable, no value is published rather than an unreliable one.
Full methodology ›Elder-services access
0.17 per 1,000 residents
in the top 8.6% nationally
Higher is healthier
ST86thUS91stDefinition & source ›
The number of services for older adults and people with disabilities inside this ZIP’s boundary, per 1,000 residents.
Counted from establishments located inside this ZIP’s boundary, so one just across the line is not counted. Where a ZIP has too few residents for the density to be reliable, no value is published rather than an unreliable one.
Full methodology ›Lead in tap water
5.1 ppb
in the top 9.7% nationally
Lower is healthier
US90thDefinition & source ›
The lead level at the 90th percentile of tap-water samples reported by the public water systems serving this ZIP, in parts per billion — the EPA requires action above 15 ppb.
Measured from EPA records for the public water systems that serve this ZIP. Households on private wells — roughly 30% of the US population — are not covered by this measure, and this figure says nothing about their water.
Full methodology ›Outpatient-care access
0.43 per 1,000 residents
in the top 10.3% nationally
Higher is healthier
ST92ndUS90thDefinition & source ›
The number of outpatient clinics located inside this ZIP’s boundary, per 1,000 residents.
Counted from establishments located inside this ZIP’s boundary, so one just across the line is not counted. Where a ZIP has too few residents for the density to be reliable, no value is published rather than an unreliable one.
Full methodology ›Subsidized affordable housing
114 units
in the top 17% nationally
Higher is healthier
ST93rdUS83rdDefinition & source ›
The number of affordable rental units in this ZIP supported by the federal Low-Income Housing Tax Credit program.
Full methodology ›The read
On balance, and by the composite measure, Knoxville, Iowa (ZIP 50138) ranks in the top 32% healthiest ZIPs nationally (10,392nd) and the top 34% of Iowa (314th).
Neither strongly one way nor the other, the measures sit mixed: distance to an emergency room is at the national minimum, shared with about 11% of ZIPs. Mental-health providers stands in the top 5.5% nationally, and modeled short sleep settles in the bottom 6.2% nationally. Civic lies in the top 7.8% nationally, elder services resides in the top 8.6% nationally, and outpatient lands in the top 10.3% nationally. Against that, modeled radon registers in the top 2.3% nationally, lithium in drinking water sits in the top 1.7% nationally, and modeled binge drinking rests in the top 7.0% nationally. Lead in tap water is in the top 9.7% nationally.
In plainer terms, radon is a radioactive soil gas the EPA identifies as the top cause of lung cancer in nonsmokers. Lithium in drinking water is a natural metal that dissolves into some groundwater and has no federal drinking-water limit yet. Lead in tap water is the EPA trigger, 15 parts per billion in tap samples, above which a water system must act on lead. For a healthier nearby ZIP overall, look to ZIP 50139, just across the boundary.
What’s driving this score
Nine domains make up the ZipVitals Score — here is how this ZIP does on each, and how much each one counts.
Compared with the ZIP codes measured across all nine scoring domains — not with all US ZIP codes.
Lifting this score
Social Need / SDOH
healthier than 74%
16%
Preventive Care
healthier than 76%
13%
Mental Health
healthier than 66%
8%
Disability
healthier than 66%
7%
Healthcare Access
in the top 0.00%
5%
About typical
Chronic Disease Burden
healthier than 56%
21%
Risk Behavior
healthier than 58%
11%
Holding it back
Environmental Hazard
healthier than 14%
14%
Climate / Disaster Risk
healthier than 32%
5%
Lifting this score
Social Need / SDOH
healthier than 87%
16%
Risk Behavior
healthier than 84%
11%
Disability
healthier than 61%
7%
Healthcare Access
in the top 0.00%
5%
About typical
Chronic Disease Burden
healthier than 60%
21%
Preventive Care
healthier than 54%
13%
Holding it back
Environmental Hazard
healthier than 13%
14%
Mental Health
healthier than 25%
8%
Climate / Disaster Risk
healthier than 12%
5%
“Share” is how much of this ZIP’s score the domain accounts for. Percentages are rounded; higher is healthier in every domain. How the score works, and who it compares you with ›
Findings that name this ZIP
2 of our published findings list this ZIP code. Each finding compares one published measure against a stated benchmark, and names only the ZIP codes whose estimates are reliable enough to rank. See all surprising findings.
Below what income predicts
The ZIP codes that outlive their incomes
Estimated life expectancy is 76.3 ± 1.3 years. A median household income of $74,693 predicts 78.9 years — 2.6 years below.
Ranked #3,613 of the 5,842 ZIP codes this finding names, ordered by years above what income predicts, highest first.
Below its nearby ZIPs
The ZIP codes that outlive their neighbors
Estimated life expectancy is 76.3 ± 1.3 years. The 50 nearest ZIP codes with estimates average 79.8 years — 3.5 years below them.
Ranked #2,693 of the 3,687 ZIP codes this finding names, ordered by years above the nearby-ZIP average, highest first.
Nearby & similar ZIPs
Editorially selected — see how this ZIP compares to nearby and similar places.
Nearby
50044
Iowashares a border
Score 50.64
Closest healthier
50139
Iowashares a border
Score 54.80
Similar health profile
62243
Illinois96% similar profile
Score 55.44
How these were chosen: only ZIPs with a published Score appear — a nearby ZIP with too little data to score won’t. Nearby means closest by distance between ZIP boundaries, which can cross state lines. A similar health profile is a close match across the nine Score domains, not similar demographics. Distances are measured between ZIP boundaries — ZIPs that touch share a border. How distance is measured
Evidence
Every measure this page draws on, by source. Collapsed by default — the full data stays in the page for search engines either way.
Health OutcomesCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Arthritis among adults | 29.4% | 26.1–32.9 |
| High blood pressure among adults | 36.7% | 32.7–40.9 |
| Cancer (non-skin) or melanoma among adults | 10.1% | 9.1–11.1 |
| Current asthma among adults | 10.0% | 8.8–11.3 |
| Coronary heart disease among adults | 7.1% | 6.3–7.9 |
| Chronic obstructive pulmonary disease among adults | 7.3% | 6.5–8.3 |
| Depression among adults | 21.5% | 18.3–25.0 |
| Diagnosed diabetes among adults | 11.6% | 10.0–13.3 |
| High cholesterol among adults who have ever been screened | 36.4% | 32.2–40.8 |
| Obesity among adults | 41.1% | 34.0–48.6 |
| Stroke among adults | 3.5% | 3.2–3.8 |
| All teeth lost among adults aged >=65 years | 11.1% | 9.0–13.5 |
PreventionCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Current lack of health insurance among adults aged 18-64 years | 6.2% | 5.2–7.4 |
| Taking medicine to control high blood pressure among adults with high blood pressure | 78.9% | 75.9–81.7 |
| Visits to doctor for routine checkup within the past year among adults | 78.6% | 75.1–82.1 |
| Cholesterol screening among adults | 86.0% | 84.2–87.8 |
| Colorectal cancer screening among adults aged 45–75 years | 68.6% | 63.9–73.3 |
| Visited dentist or dental clinic in the past year among adults | 69.1% | 65.8–72.3 |
| Mammography use among women aged 50-74 years | 78.7% | 71.6–84.8 |
Health Risk BehaviorsCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Binge drinking among adults | 19.8% | 16.5–23.4 |
| Current cigarette smoking among adults | 15.0% | 12.9–17.3 |
| No leisure-time physical activity among adults | 24.4% | 20.6–28.6 |
| Short sleep duration among adults | 29.1% | 23.6–35.1 |
Health StatusCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Fair or poor self-rated health status among adults | 17.8% | 15.5–20.3 |
| Frequent mental distress among adults | 16.2% | 14.3–18.2 |
| Frequent physical distress among adults | 13.1% | 11.5–14.8 |
DisabilityCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Cognitive disability among adults | 13.3% | 11.7–15.0 |
| Any disability among adults | 30.2% | 26.4–34.3 |
| Hearing disability among adults | 8.1% | 7.2–9.1 |
| Independent living disability among adults | 7.4% | 6.5–8.3 |
| Mobility disability among adults | 13.8% | 12.0–15.8 |
| Self-care disability among adults | 3.4% | 3.1–3.8 |
| Vision disability among adults | 4.2% | 3.8–4.6 |
Health-Related Social NeedsCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Lack of social and emotional support among adults | 22.5% | 19.2–25.9 |
| Food insecurity in the past 12 months among adults | 10.6% | 8.9–12.5 |
| Received food stamps in the past 12 months among adults | 8.9% | 7.5–10.5 |
| Housing insecurity in the past 12 months among adults | 8.2% | 6.9–9.6 |
| Lack of reliable transportation in the past 12 months among adults | 6.1% | 5.3–6.9 |
| Loneliness among adults | 30.5% | 26.0–35.3 |
| Utility services shut-off threat in the past 12 months among adults | 5.7% | 4.9–6.6 |
Community & economyCensus ACS 5-Year · 2024 release · observed
| Measure | Value | US median (p10–p90) | IA median (p10–p90) |
|---|---|---|---|
| Poverty rate | 10.5% | 10.6% (3.1–25.8%) n=32,364 | 8.5% (2.7–19.1%) n=931 |
| Uninsured 18–64 | 4.7% | 9.0% (1.5–24.3%) n=32,286 | 5.4% (0.7–14.7%) n=931 |
| No HS diploma (25+) | 6.7% | 7.9% (1.8–20.7%) n=32,505 | 5.1% (1.6–12.9%) n=932 |
| Bachelor's or higher (25+) | 28.0% | 23.3% (9.2–53.6%) n=32,505 | 20.9% (9.8–36.8%) n=932 |
| Unemployment rate (16+) | 3.7% | 3.9% (0.0–9.8%) n=32,274 | 2.2% (0.0–6.7%) n=932 |
| Households without a vehicle | 3.6% | 3.9% (0.0–12.5%) n=32,322 | 2.4% (0.0–7.9%) n=931 |
| Broadband subscription | 83.3% | 89.3% (75.1–97.1%) n=32,322 | 88.5% (77.9–95.1%) n=931 |
| Housing cost burden (≥30% income) | 21.2% | 23.7% (10.6–40.0%) n=32,322 | 18.2% (9.0–28.8%) n=931 |
| Homeownership rate | 80.9% | 78.7% (51.7–94.0%) n=32,322 | 82.1% (66.8–93.5%) n=931 |
| Crowded housing (>1 per room) | 1.7% | 1.3% (0.0–6.3%) n=32,322 | 0.4% (0.0–3.3%) n=931 |
| Foreign-born population | 1.5% | 2.6% (0.0–18.6%) n=32,553 | 1.0% (0.0–7.2%) n=932 |
| Single-parent households | 60.6% | 53.6% (37.3–74.1%) n=32,087 | 56.8% (43.7–75.5%) n=928 |
| Population 65+ | 22.1% | 19.4% (10.8–33.6%) n=32,553 | 20.2% (12.7–31.0%) n=932 |
| Median age | 42.9 yr | 42.2 yr (33.0–56.3) n=32,292 | 42.7 yr (34.1–54.7) n=931 |
| Median household income | $74,693 | $72,070 ($46,039–$118,707) n=30,318 | $73,848 ($55,055–$102,762) n=911 |
| Median home value | $196,700 | $222,200 ($100,300–$579,820) n=30,049 | $161,100 ($93,820–$278,170) n=892 |
| Median gross rent | $815 | $1,021 ($677–$1,912) n=25,670 | $825 ($614–$1,113) n=771 |
Life expectancyNCHS / RWJF USALEEP · model-based
| Measure | Value | US median (p10–p90) | IA median (p10–p90) |
|---|---|---|---|
| Life expectancy at birth | 76.3 yr ± 0.66 | 78.9 yr (74.7–82.8) n=31,308 | 80.0 yr (77.2–83.4) n=917 |
About the ± — it’s this estimate’s give-or-take (statisticians call it the standard error). The true life expectancy for this ZIP most likely falls within 0.66 years of 76.3, and it’s very unlikely to be off by more than twice that.
More ZIPs to explore ▾More ZIPs to explore ▴
How these lists were built: they draw only from ZIPs that have a published Score, so ZIPs with too little data to score are not listed. Distance-based lists use distance between ZIP boundaries with no state filter, so an out-of-state ZIP can appear. Statistically similar means a close match across the nine Score domains, not a demographic match: the measure is the cosine similarity between two ZIPs’ domain scores, taken over the domains both ZIPs have data for and only where that overlap covers at least six of the nine — and where no ZIP clears that minimum-overlap floor, that list is left out rather than filled with a weak match. How distance is measured