Trust Score Methodology

Every vendor on The Longevity Agent receives a trust score from 1-10. Here is exactly how we determine those scores, what each tier means, and what earned each vendor their rating.

Scoring Tiers

10/10Gold Standard

Manufacturer-direct sales, publishes batch COAs (Certificates of Analysis), NSF/USP certified, zero FDA warning letters, extensive third-party testing program.

9/10Excellent

Manufacturer-direct OR specialized retailer with extensive third-party testing, strong quality track record, transparent sourcing, science-focused formulations.

8/10Very Good

Direct-ship retailer with good testing practices, climate-controlled warehouses, established reputation, OR manufacturer with solid but not industry-leading testing.

7/10Good

Established retailer or brand with standard quality controls, GMP certified, no major quality issues or FDA warnings. Mass-market brands with long track records.

6/10Acceptable

Budget brand with limited testing transparency but no known quality issues. GMP certified, third-party tested but with less documentation available publicly.

5/10Mixed

Mixed track record or limited quality data available. May be newer brands without established history, or brands with minor quality concerns.

2/10Caution

Commingled inventory risk (Amazon marketplace model), known counterfeit issues, or documented quality failures. Products may not be what the label claims.

What We Evaluate

Third-Party Testing

Does the vendor/brand test products through independent labs? Do they publish Certificates of Analysis (COAs)?

Certifications

NSF Certified for Sport, USP Verified, GMP certified, USDA Organic, Non-GMO Project Verified, etc.

Supply Chain Control

Does the company control their supply chain from sourcing to shipping? Or can third-party sellers introduce counterfeit product (commingled inventory)?

FDA Compliance

Any FDA warning letters, recalls, or regulatory actions? Clean regulatory history?

Storage & Shipping

Climate-controlled warehouses? Proper cold chain for sensitive products? Direct-ship vs marketplace model?

Transparency

Does the company openly share sourcing, testing results, and manufacturing practices?

Track Record

How long has the company been operating? Any documented quality incidents?

Vendor Scores

Thorne

Direct Ship

Physician-grade supplements. NSF Certified for Sport. Direct from manufacturer. Publishes extensive research and third-party testing.

Life Extension

Direct Ship

Premium longevity-focused brand. Heavy investment in research. Ships direct. Extensive third-party testing program.

Nootropics Depot

Direct Ship

Industry-leading third-party testing. Publishes COAs for every batch. Enthusiast favorite for nootropics and longevity compounds.

Pure Encapsulations

Direct Ship

Hypoallergenic supplements. Free from common allergens, artificial additives, and unnecessary excipients. Physician-recommended.

iHerb

Direct Ship

Direct-ship retailer with rigorous quality control. Ships from climate-controlled warehouses. Extensive catalog with competitive pricing.

Jarrow Formulas

Direct Ship

Science-focused formulations. Strong emphasis on clinically studied forms of nutrients. Good manufacturing practices and testing.

Nordic Naturals

Direct Ship

Omega-3 specialist. Friend of the Sea certified. Third-party tested for purity. Award-winning fish oil products.

Momentous

Direct Ship

Huberman Lab partner brand. NSF Certified for Sport. Third-party tested. Premium pricing but high quality standards.

NOW Foods

Direct Ship

One of the largest supplement manufacturers. GMP certified facilities. Huge catalog with budget-friendly pricing. Family-owned since 1968.

Swanson Vitamins

Direct Ship

Value-oriented retailer with extensive catalog. Good quality controls and competitive pricing. Ships from own warehouses.

Vital Proteins

Direct Ship

Collagen specialist. NSF Contents Certified. Sourced from grass-fed, pasture-raised bovine. Strong brand recognition.

Garden of Life

Direct Ship

Organic and whole-food based supplements. USDA Organic certified. Non-GMO Project Verified. B Corporation.

Nature's Way

Direct Ship

Established mass-market brand since 1969. TRU-ID certified for botanical identity. Broad retail distribution.

Bulk Supplements

Direct Ship

No-frills powder supplements. Lab tested for purity. Minimal packaging, maximum value. Limited transparency on sourcing.

Nutricost

Direct Ship

Budget brand with clean formulations. Third-party tested. GMP certified. Good value for common supplements.

Amazon

Marketplace

Commingled inventory risk. University of Mississippi study found 57% of supplements tested from Amazon failed quality testing. Third-party sellers may sell counterfeit products.

Trust scores are our editorial assessment based on publicly available information. We earn affiliate commissions from all vendors listed. Scores are not influenced by commission rates. We recommend against Amazon for supplements despite earning commissions from them.