Immune Resilience Support

Written by Dr. Ryan Kneessi, ND

The mechanisms this protocol supports

Your immune system starts at the barriers, especially the lining of the airways and the gut, where immune cells constantly sample what comes in. Vitamin D receptors sit on many of those immune cells, and zinc is needed for immune cells to develop and send signals.

Most immune tissue lives in the gut, so the gut microbiome helps train how the immune system responds everywhere else. With age, immune function gradually changes in a process called immunosenescence, and nutrient status becomes even more important.

Research has linked low vitamin D and zinc status with weaker immune defenses, and an individual-participant meta-analysis linked vitamin D supplementation with fewer acute respiratory infections, mostly in people who started out low. This protocol supports those underlying mechanisms and does not replace medical care when you are sick.

What is in the protocol

The exact products and directions are listed in the Fullscript plan, and here is what each one is commonly used to support.

• Vitamin D + K2 Liquid from Thorne provides vitamin D, which immune, muscle and bone cells all rely on, together with vitamin K2, which helps direct calcium into bone.
• Zinc Picolinate from Thorne provides a well-absorbed form of zinc, a mineral needed for immune cell development and signaling.
• Buffered Ascorbic Acid from Pure Encapsulations provides a gentle form of vitamin C, which builds up inside immune cells and supports barrier function.
• Quercetin Phytosome from Thorne provides quercetin, a plant flavonoid that influences inflammatory and immune signaling, in a form designed for better absorption.
• Ther-Biotic Synbiotic from Klaire Labs is a multi-strain probiotic paired with a prebiotic, and reviews of probiotic trials have linked them with fewer and shorter upper respiratory infections.

Related protocols you may find helpful include Gut Barrier & Microbiome and Sleep & Overnight Repair.

How to use it thoughtfully

Please talk with your provider before starting, especially if you take medications, are pregnant or nursing, or have a health condition. This page does not list amounts, so follow the label or the specific guidance your provider gives you. When you can, add one product at a time so it is easier to notice how you feel. Sleep, nourishing food, daily movement and stress care are the foundation, and supplements are meant to build on them.

Zinc used for long periods can lower copper levels, so check with your provider about how long to use it. Vitamin K2 can interact with warfarin, so please check with your prescriber before starting if you take a blood thinner. Quercetin may interact with some medications that are cleared by the liver, so mention it to your prescriber or pharmacist. High fever, trouble breathing or symptoms that keep getting worse need prompt medical care.

What the research shows

This protocol has not been tested as a whole in a clinical trial, so the studies below cover its main ingredients.

For vitamin D, a 2017 BMJ meta-analysis by Martineau and colleagues of 25 trials with 11,321 people found about 12% lower odds of acute respiratory infection overall, with the largest benefit in people who started very low and in those taking daily or weekly doses.

For vitamin C, a 2013 Cochrane review by Hemilä and Chalker of 29 trials with 11,306 people found that regular use did not reduce how often colds started in the general population, but shortened them by about 8% in adults and 14% in children. Starting vitamin C only after symptoms appeared showed no consistent effect.

For zinc, a 2017 analysis by Hemilä and colleagues pooled individual data from 3 trials with 199 adults using zinc acetate lozenges (80 to 92 mg of zinc a day). By day 5, 70% of the zinc group had recovered compared with 27% on placebo. These were small trials of lozenges, which act in the throat, so the results do not apply to zinc capsules.

Frequently asked questions

Sources

• Prasad AS. Zinc in human health: effect of zinc on immune cells. Mol Med 2008. PMID: 18385818. https://pmc.ncbi.nlm.nih.gov/articles/PMC2277319/
• Belkaid Y, Hand TW. Role of the microbiota in immunity and inflammation. Cell 2014. PMID: 24679531. https://pmc.ncbi.nlm.nih.gov/articles/PMC4056765/
• Martineau AR, et al. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. BMJ 2017. PMID: 28202713. https://pmc.ncbi.nlm.nih.gov/articles/PMC5310969/
• Carr AC, Maggini S. Vitamin C and Immune Function. Nutrients 2017. PMID: 29099763. https://pmc.ncbi.nlm.nih.gov/articles/PMC5707683/
• Hao Q, Dong BR, Wu T. Probiotics for preventing acute upper respiratory tract infections. Cochrane Database Syst Rev 2015. PMID: 25927096. https://pubmed.ncbi.nlm.nih.gov/25927096/

Browse all A-Z protocols