Nancy Lannan, RD, LDN
Nancy Lannan, RD, LDN is a Pediatric Nutrition Registered Dietitian in Downers Grove, IL, registered under NPI 1518081009. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 2901 FINLEY RD SUITE 102, Downers Grove, IL 60515. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 164002532 | IL | Registered Dietitian |
| 164002532 | IL | Pediatric Nutrition Registered Dietitian primary |
This provider holds licence 164002532 issued in IL. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Nutrition, Pediatric covers
An individual who is a Board Certified Specialist in Pediatric Nutrition and applies evidence-based nutrition knowledge in providing medical nutrition therapy for pediatric patients. Specialists work directly with healthy and/or ill children (newborn up to 21 years of age) as well as children with special health care needs in a variety of settings (hospitals, community-based and/or family-centered programs, education programs, home, etc.), OR indirectly through management, care coordination, education, quality improvement, or research practice linked specifically to pediatric nutrition. NUCC Health Care Provider Taxonomy, code 133VN1004X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 133V00000X | Registered Dietitian | 164002532 | IL | |
| 133VN1004X | Pediatric Nutrition Registered Dietitian Nutrition, Pediatric | 164002532 | IL | primary |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1518081009 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 19, 2007 |
| Last updated | Sep 11, 2025 |
| Status | Active |
| Sole proprietor | No |
| Gender | Female |
| Credential | RD, LDN |
| Practice address |
2901 FINLEY RD SUITE 102 Downers Grove, IL 60515 (630) 495-6800 Fax (630) 495-8200 |
| Mailing address |
811 N KENSINGTON AVE La Grange Park, IL 60526 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 5 | 1 | 8 | 0 | 8 | 1 | 0 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 5 | 2 | 8 | 0 | 8 | 2 | 0 | 0 |
Sum = 51 · next multiple of 10 = 60 · check digit = 9 · actual last digit = 9
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.