11 Supplements Beyond Vitamin C: Your Must-Have Checklist for Cold Season

3. Zinc — The Viral Attachment Blocker

Zinc shows up repeatedly in conversations about early cold defense because it helps block viruses from attaching to cells and supports immune response. Medical contributors included in the research describe zinc as particularly useful right at symptom onset. That timing is one of the most important takeaways: zinc tends to work best when used at the very start of a sore throat or scratchy nose rather than weeks in advance. There is discussion among experts about whether to use small maintenance doses daily or save zinc for early symptom use—opinions vary and practical approaches depend on personal tolerance. Long-term high doses can cause stomach upset and, in rare cases, disturb copper balance, so avoid prolonged mega-dosing unless supervised by a clinician. If you choose lozenges, follow label instructions about timing and avoid taking iron or high-dose calcium at the same moment, since minerals can interfere with each other. Zinc is an accessible, targeted tool that many find helpful for cutting the length or severity of an early cold when used correctly.

4. NAC (N-Acetyl-Cysteine) — Respiratory and Antioxidant Support

NAC is an amino acid precursor that helps the body make glutathione, a key intracellular antioxidant involved in respiratory health and cellular defense. Nutrition experts and clinicians included in the research list NAC among useful winter supports, especially for people with respiratory sensitivities or recurring chest congestion. A commonly referenced supplemental dose in the findings is 600 mg, which is used in many clinical and wellness contexts. NAC may thin mucus and support antioxidant pathways, making it a practical tool for people who struggle with thicker secretions during colds. Because NAC can affect certain blood markers and interact with prescription medications, it’s wise to discuss it with your clinician before starting, particularly if you take blood thinners or have chronic liver conditions. For many, NAC is a focused strategy to add when respiratory symptoms appear or during high-risk periods rather than an all-season staple; that makes it a useful entry in a cold-season toolbox when guided by a professional.