Skip to main content

St. Clair County, Illinois

Moderate risk

Gera County Health Risk Index: 54.9/100 · National rank 102 of 480 · Population: 251,018 · CDC PLACES June 2026

What is the chronic-disease health risk in St. Clair County, Illinois?

As of June 2026, St. Clair County, Illinois has a Gera County Health Risk Index of 54.9/100 (national rank 102/480; moderate risk). Adult chronic-disease prevalence: obesity 38.8%, diabetes 13.1%, coronary heart disease 6.5%, smoking 14.2%. Source: CDC PLACES June 2026.

Source:CDC PLACES: Local Data for Better Health, County Data 2023 release·as of June 2026updated annually (last: )
Gera County Health Risk Index54.9 / 100Rank 102 of 480 most-populous US counties. Computed from CDC PLACES June 2026 crude prevalence for 4 chronic-disease measures, weighted and normalised 0–100. Higher = higher risk.How this index is calculated

Chronic-disease prevalence — St. Clair County (CDC PLACES June 2026)

St. Clair County, Illinois — CDC PLACES June 2026 crude prevalence (adults)
MeasurePrevalenceWeight in GCHRI
Obesity38.8%25%
Diagnosed diabetes13.1%25%
Coronary heart disease6.5%30%
Current cigarette smoking14.2%20%
GCHRI composite score54.9 / 100—

Check another county's health risk

Search any of the 480 most-populous US counties to compare GCHRI scores and CDC prevalence rates.

St. Clair County, Illinois

Population: 251,018 · National rank: 102 / 480 (by chronic-disease risk)

Moderate risk

Gera County Health Risk Index

54.9 / 100

Obesity

38.8%

adults

Diabetes

13.1%

adults

Heart Disease

6.5%

adults

Smoking

14.2%

adults

Source: CDC PLACES, June 2026 · Crude prevalence, adults · Full county page →

Other counties in Illinois

← View all 480 counties

Frequently asked questions

What is the Gera County Health Risk Index for St. Clair County, IL?
St. Clair County, IL has a Gera County Health Risk Index (GCHRI) of 54.9/100, ranking 102 out of 480 most-populous US counties (rank 1 = highest chronic-disease risk). This places it in the moderate-risk tier. Source: CDC PLACES (June 2026).
What is the obesity rate in St. Clair County?
The adult obesity prevalence in St. Clair County, IL is 38.8% (CDC PLACES, June 2026, crude prevalence). The national mean across the 480 included counties is 38.8%.
What is the diabetes rate in St. Clair County?
The diagnosed diabetes prevalence among adults in St. Clair County, IL is 13.1% (CDC PLACES, June 2026, crude prevalence).
What is the coronary heart disease rate in St. Clair County?
The coronary heart disease prevalence among adults in St. Clair County, IL is 6.5% (CDC PLACES, June 2026, crude prevalence).
What is the smoking rate in St. Clair County?
The current cigarette smoking prevalence among adults in St. Clair County, IL is 14.2% (CDC PLACES, June 2026, crude prevalence).

Concerned about health risks in St. Clair County?

A GeraClinic care navigator can help you understand what these CDC chronic-disease rates mean for you personally, assess your individual risk factors, and connect you with preventive-care resources — fully online.

Talk to a GeraClinic care navigatorHow the Gera County Health Risk Index is calculated

Contains public sector information published by U.S. Centers for Disease Control and Prevention (CDC) and licensed under the U.S. Public Domain (federal government work, 17 U.S.C. § 105). Source: CDC PLACES: Local Data for Better Health, County Data 2023 release (June 2026, published 2023 (released 2024)).

Informational/educational only — not a substitute for professional medical advice; a clinician interprets results.