Joyce Giammattei, DRPH, RD, CDE
Joyce Giammattei, DRPH, RD, CDE is a Metabolic Nutrition Registered Dietitian in Sonoma, CA, registered under NPI 1194861450. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 430 W NAPA ST STE F, Sonoma, CA 95476. 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 |
|---|---|---|
| 818435 | CA | Metabolic Nutrition Registered Dietitian primary |
This provider holds licence 818435 issued in CA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Registered Dietitian Or Nutrition Professional
- PAC ID
- 5799762324
Medicare enrolment is recorded as approved under the provider type Practitioner - Registered Dietitian Or Nutrition Professional. This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Nutrition, Metabolic covers
A registered dietitian who achieves specialized competency in metabolic nutrition. NUCC Health Care Provider Taxonomy, code 133VN1006X
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 | 1194861450 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jan 30, 2007 |
| Last updated | Jul 13, 2007 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | DRPH, RD, CDE |
| Practice address |
430 W NAPA ST STE F Sonoma, CA 95476 (707) 939-6070 |
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 | 1 | 9 | 4 | 8 | 6 | 1 | 4 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 1 | 9 | 4 | 7 | 6 | 2 | 4 | 1 |
Sum = 60 · next multiple of 10 = 60 · check digit = 0 · actual last digit = 0
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.