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MARY SEIERSEN RDE
NPI 1538282983
Dietitian, Registered in Los Alamitos, CA

Active since April 09, 2007
3851 KATELLA AVE STE 275, LOS ALAMITOS, CA 90720(562) 296-5528(562) 296-8506 Get Directions Write a Review

NPPES record last updated: December 28, 2023. Verified against the NPPES registry weekly; last sync: November 01, 2026.

About Mary Seiersen Rde NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MARY SEIERSEN RDE (NPI 1538282983) is an individual dietitian, registered in Los Alamitos, California and active in the NPI registry since April 2007.

NPPES Registry Identity

NPI1538282983
Entity TypeIndividualFemale
Primary Taxonomy133V00000X
Provider Legal NameMARY SEIERSENCredential: RDE
Location Address3851 KATELLA AVE STE 275Los Alamitos, CA 90720-3377
Mailing Address15464 Goldenwest StWestminster, CA 92683-6149 · (714) 891-9008 · Fax (714) 893-2239
Phone(562) 296-5528
Fax(562) 296-8506
Sole ProprietorNo
Enumeration DateApril 9, 2007
Last NPPES UpdateDecember 28, 2023
NPPES CertifiedDecember 28, 2023
✔ NPI 1538282983 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 3

★ Primary SpecialtyDietitian, RegisteredDietary & Nutritional Service Providers
Taxonomy Code133V00000X
Definition
A Registered Dietitian (RD)/Registered Dietitian Nutritionist (RDN) is an individual uniquely trained in the science of nutrition and practice of dietetics to design and provide medical nutrition therapy (MNT) and other evidence-based applications of the Nutrition Care Process (NCP) that exemplify the profession's systematic approach to providing high quality nutrition care. Registered dietitians provide MNT for the purpose of disease prevention or management, or to treat or rehabilitate an illness, injury, or condition, with the use of specific, indicated physical and cognitive nutrition care services comprised of one or more of the following aspects of the NCP: nutrition assessment/reassessment, nutrition diagnosis, nutrition intervention (e.g., nutrition counseling, therapeutic diet ordering, and nutrition education) and nutrition monitoring and evaluation.
Also ListedNutritionistTaxonomy 133N00000X
Also ListedRegistered Nurse · Diabetes EducatorTaxonomy 163WD0400X · License 711000 (CA)
3851 KATELLA AVE STE 275, Los Alamitos, CA 90720
Open in Google Maps ↗

Other Identifiers 1

Other711000CA · State License #

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mary Seiersen Rde is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Medicare Billing Reassignment

Medicare enrollment records show Mary Seiersen reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Prohealth Partners, A Medical Group, Inc.
Same address
Family Medicine
3851 KATELLA AVE, SUITE 275
Los Alamitos, CA 90720
  • Reassigned Medicare billing, California enrollment
  • 279 clinicians in this Medicare group
NPI 1710201801 (562) 296-5528

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Other Providers at the Same Location NPPES 2

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

JK LOOMIS CORP A MEDICAL CORP
Family Medicine
3851 KATELLA AVE STE 275
LOS ALAMITOS, CA 90720
Orange County (562) 296-5528
VERONICA ZOLETA NP
Nurse Practitioner (Family)
3851 KATELLA AVE STE 275
LOS ALAMITOS, CA 90720
Orange County (562) 296-5528

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Mary Seiersen's NPI number?

The NPI number for Mary Seiersen is 1538282983. It was assigned to this individual provider in the NPPES registry on April 9, 2007.

Where is Mary Seiersen located?

Mary Seiersen practices at 3851 Katella Ave Ste 275, Los Alamitos, CA 90720. The listed phone number is (562) 296-5528.

What is Mary Seiersen's specialty?

The primary specialty registered for this NPI is Dietitian, Registered with taxonomy code 133V00000X.

Is Mary Seiersen enrolled in Medicare?

Yes. Mary Seiersen is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Mary Seiersen's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mary Seiersen reassigns Medicare benefits to Prohealth Partners, A Medical Group, Inc. (Los Alamitos, CA). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Mary Seiersen's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Mary Seiersen was last updated on December 28, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.