Natural Evidence-Based Self-Treatment for Colds and Flu

By Dr. J.E. Williams | | Reading Time: 3 minutes

Natural Evidence-Based Self-Treatment for Colds and Flu

The 2023/2024 colds and flu season is just beginning. Cases are increasing, and hospitalizations are above the average baseline. What can you do to reduce your risk and shorten your sick time if you get infected? Do natural remedies work?

For decades, I have recommended taking zinc and selenium and boosting vitamin C to prevent and treat seasonal respiratory viral infections. For active infections, I advise adding echinacea tincture. These are standard naturopathic treatments. But do these natural remedies work? And what is the evidence?

Here’s a summary of what I found from a PubMed and Cochrane Review search.

A 2011 review found vitamin C ineffective for treating a common cold but valuable for prevention when taken regularly during the colds and flu season. Doses of 1-2 grams (1,000-2,000 mg) daily were most effective.

A 2013 review of thirty trials found that vitamin C as a treatment barely made a difference but had some value for prevention.

A 2021 study on vitamin C was a meta-analysis compared ten randomized controlled trials involving 1048 patients in China. This study found that vitamin C helped reduce common cold symptoms, including coughing. It also enhanced immunity, improving the ability of white blood cells to kill viruses.

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Zinc did a little better. Selenium hardly helped at all. However, selenium deficiency is associated with lower overall immune function. Be sure to get sufficient selenium and take optimal doses of zinc.

Echinacea was helpful but didn’t make a significant difference. Both tincture and standardized extracts of 4% echinacosides are helpful. I prefer capsules for prevention and the liquid tincture for acute symptoms due to its faster absorption.

Based on my 40 years of clinical experience and research, these supplements help prevent and shorten sick days if you get a cold or the flu. They may have an additive advantage when taken together.

If you are to take just one, use vitamin C. Remember, they don’t “knock out” a cold or the flu. However, they provide immune support that reduces symptom intensity and shortens sick days.

To prevent and shorten sick days taken twice daily:

Buffered Ascorbic Acid: 2-3,000 mg (capsules or powder)
Zinc picolinate, gluconate, or acetate: 60-75 mg (capsules or lozenges)
Echinacea capsules or tincture: 250 mg (tincture or capsule)

Note on Dosing: These are average recommendations for prevention in adults and teens. When you have acute symptoms, take each four times daily. Children should take 30-50% less.

Here are the brands I recommend, which you’ll find on Fullscript.

Colds and Flu Prevention 1

Start now to help prevent colds and flu. Remember, the best prevention is not to get sick.

Dr. Williams


Cerullo G, Negro M, Parimbelli M, Pecoraro M, Perna S, Liguori G, Rondanelli M, Cena H, D’Antona G. The Long History of Vitamin C: From Prevention of the Common Cold to Potential Aid in the Treatment of COVID-19. Front Immunol. 2020 Oct 28;11:574029. doi: 10.3389/fimmu.2020.574029. PMID: 33193359; PMCID: PMC7655735.
DeGeorge KC, Ring DJ, Dalrymple SN. Treatment of the Common Cold. Am Fam Physician. 2019 Sep 1;100(5):281-289. PMID: 31478634.
Douglas RM, Hemilä H, Chalker E, Treacy B. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2007 Jul 18;(3):CD000980. doi: 10.1002/14651858.CD000980.pub3. Update in: Cochrane Database Syst Rev. 2013;1:CD000980. PMID: 17636648.
Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2013 Jan 31;2013(1):CD000980. doi: 10.1002/14651858.CD000980.pub4. PMID: 23440782; PMCID: PMC8078152.
Ran L, Zhao W, Wang H, Zhao Y, Bu H. Vitamin C as a Supplementary Therapy in Relieving Symptoms of the Common Cold: A Meta-Analysis of 10 Randomized Controlled Trials. Biomed Res Int. 2020 Oct 9;2020:8573742. doi: 10.1155/2020/8573742. Erratum in: Biomed Res Int. 2021 Apr 27;2021:9875417. PMID: 33102597; PMCID: PMC7569434.
Singh M, Das RR. Zinc for the common cold. Cochrane Database Syst Rev. 2015 Apr 30;2015(4):CD001364. doi: 10.1002/14651858.CD001364.pub5. PMID: 25924708; PMCID: PMC6457799.
Zhang, J., Saad, R., Taylor, E. W., & Rayman, M. P. (2020). Selenium and selenoproteins in viral infection with potential relevance to COVID-19. Redox Biology, 37, 101715.