Evidence-Based Compounds for a Stronger Immune System

⏰ Daily with meals; increase during acute illness

💡 Vitamin D is arguably the single most important immune supplement. COVID data showed massive outcome differences between D-sufficient and D-deficient patients. Test your levels and supplement accordingly. Quercetin acts as a zinc ionophore — it helps zinc enter cells where it blocks viral replication.

Can supplements prevent colds?

Vitamin D supplementation reduces respiratory infection risk by 12-75% depending on baseline deficiency. Zinc lozenges (not pills) reduce cold duration by ~33% if started within 24 hours of symptoms. Vitamin C has modest prevention benefit but real treatment benefit at high doses.

How much vitamin D should I take?

Most adults need 3000-5000 IU daily to maintain 50-70 ng/mL blood levels. If you're severely deficient (<20 ng/mL), a loading protocol of 10,000 IU daily for 8 weeks may be needed. Always take D3 (not D2) with dietary fat, and pair with K2 MK-7 to prevent calcium deposition.

Is elderberry safe during COVID?

Early concerns about elderberry causing a cytokine storm were theoretical and never demonstrated clinically. Current evidence suggests elderberry is safe and may reduce severity/duration of upper respiratory infections. Don't use it as a replacement for vaccination or medical treatment.

What about echinacea?

The evidence for echinacea is mixed and generally underwhelming. Some preparations may modestly reduce cold duration. It's not harmful, but vitamin D, zinc, and vitamin C have far stronger evidence. Spend your money on those first.