The 5-Second Rule
Flip the bottle. Look at the Supplement Facts panel. If you see any of these red flags, put it back:
- ✗Proprietary blend — hides individual doses. You have no idea if you're getting a therapeutic amount.
- ✗"Fish oil concentrate" without "rTG" or "re-esterified triglyceride" — almost certainly ethyl ester (poor absorption).
- ✗Beta-carotene in an eye formula — increases lung cancer risk in smokers and recent quitters.
- ✗Zinc >40 mg without copper — causes copper deficiency anemia over time.
- ✗No third-party testing seal (NSF, USP, IFOS, ConsumerLab) — you're trusting the manufacturer's word.
What to Look For (The Green Flags)
🔬 Ingredient Form Matters
| Ingredient | Good Form | Avoid |
|---|---|---|
| Omega-3 | rTG (re-esterified TG) | Ethyl ester (EE) |
| Vitamin E | d-alpha-tocopherol (natural) | dl-alpha-tocopherol (synthetic) |
| Vitamin B12 | Methylcobalamin | Cyanocobalamin |
| Magnesium | Glycinate, threonate | Oxide |
| Zinc | Picolinate, citrate | Oxide |
| Folate | Methylfolate (5-MTHF) | Folic acid |
📊 Dose Matching
Compare the label to the study that matters:
- AREDS2: Lutein 10 mg + Zeaxanthin 2 mg + Zinc 25–80 mg + Copper 2 mg
- Dry eye (DREAM/omega-3 studies): EPA + DHA ≥2,000 mg/day as rTG
- Vitamin D: 1,000–2,000 IU D3 (target blood level 40–60 ng/mL)
🏷️ Third-Party Testing Seals
These organizations test for: label accuracy, contaminants (heavy metals, PCBs), and dissolution. Look for their logos:
NSF
Certified for Sport
USP
Verified
IFOS
5-Star (fish oil)
ConsumerLab
Tested
No seal = no independent verification.
🏷️ "Other Ingredients" — What's Fine vs. Suspect
✅ Generally Fine
- • Rice flour / cellulose (capsule filler)
- • Silica (anti-caking)
- • Vegetable capsule (HPMC), vegan, clean
- • Gelatin capsule, fine if not vegan
- • Natural flavors (usually trivial amounts)
⚠️ Avoid When Possible
- • Titanium dioxide (whitener, banned in EU)
- • Artificial colors (FD&C Red #40, Blue #1, etc.)
- • Hydrogenated oils
- • Magnesium stearate (controversial, some avoid)
- • Carrageenan (some GI sensitivity)
💡 Quick Label Audit Checklist
Screenshot this. Next time you're shopping, run the label through these 5 questions:
- 1Does it have the form I need? (rTG omega-3, methylcobalamin B12, d-alpha-tocopherol E)
- 2Are doses ≥ study doses? (Check the table above)
- 3No proprietary blends? Every ingredient listed with exact amount.
- 4Third-party tested? NSF, USP, IFOS, or ConsumerLab seal.
- 5Clean "other ingredients"? No titanium dioxide, artificial colors, hydrogenated oils.
Want Our Pre-Vetted Picks?
We only recommend products that pass every check above. Doses match studies. Forms are bioavailable. Third-party tested. Affiliate links support the site at no cost to you.