COVID-19 & Immune Resilience: What the Research Says About Nutraceuticals

By Dr. Sandra McKenzie, Lifestyle Medicine Specialist

When COVID-19 emerged, much of the conversation centered around public health measures, pharmaceuticals, and day-to-day precautions. But over the last few years, researchers in integrative and functional medicine have explored another important area: how certain nutrients and botanicals may support immune balance and resilience.

While supplements do not treat or cure viral illness, more evidence now shows that key nutrients play a role in immune function, oxidative stress reduction, and inflammation balance — all of which are important during times of immune challenge.

This article provides a clear, empowering overview of what the research suggests.

The Nutraceuticals Most Studied for Immune Support

Below is an educational summary of nutrients and botanicals frequently discussed in scientific literature. No dosages are provided — all supplementation should be personalized and medically guided.

Vitamin D

Supports:

• Healthy immune regulation

• Inflammatory balance

• T-cell activation

  
  

Low vitamin D levels have been associated with increased susceptibility to respiratory infections.

Vitamin C

Supports:

• Antioxidant defenses

• Immune cell function

• Tissue repair and recovery

  
  

Vitamin C helps neutralize free radicals and may support shorter recovery times during illness.

Zinc

Supports:

• Immune cell activity

• Healthy mucosal barriers

• Normal immune signaling

  
  

Zinc is often discussed for its antiviral support in early immune response.

Quercetin

A plant flavonoid noted for:

• Antioxidant properties

• Mast cell regulation

• Potential antiviral activity

  
  

Often discussed in combination with vitamin C to support absorption.

Melatonin

Beyond sleep support, melatonin plays roles in:

• Antioxidant pathways

• Mitochondrial protection

• Inflammation balance

  
  

Research continues to explore its immune-modulating potential.

NAC (N-Acetylcysteine)

Supports:

• Glutathione production (the body’s master antioxidant)

• Respiratory health

• Detoxification pathways

• 
  

NAC is widely studied for lung and mucosal support.

Botanicals Commonly Discussed

• Elderberry: antioxidant and immune-supportive properties

• Green Tea Extract (EGCG): antiviral and anti-inflammatory potential

• Omega-3 fatty acids: support healthy inflammation response and cellular membranes

  
  

Again: These are supportive — not curative — and should be individualized.

The Lifestyle Medicine Connection

Immune health is more than supplements.

It is deeply influenced by:

• Sleep quality

• Stress regulation

• Nutrition

• Toxin exposure

• Movement

• Emotional resilience

  
  

This is why a personalized, whole-person approach matters.

Want to Know Your Immune & Environmental Stress Load?

You already have the perfect tool:

Take the Toxin Exposure Questionnaire

You’ll find it on the Resources page under Wellness Assessments & Resources

.

This questionnaire helps you identify:

• Hidden environmental burdens

• Household chemical exposure

• Food and lifestyle contributors

• Potential stressors affecting your immune resilience

  
  

It sets the stage for personalized, root-cause support.

If you're curious about which nutrients or botanicals may be appropriate for your body:

Schedule your complimentary 10-minute virtual discovery call.

CONNECT HERE

We’ll explore:

• Your health history

• Your goals

• Your symptoms

• Your current immune stressors

  
  

…and determine whether targeted nutraceutical support, lifestyle shifts, or deeper assessment is the right next step.

Disclaimer:

This content is for educational purposes only and is not intended to diagnose, treat, or prescribe. Always consult your licensed healthcare provider before beginning supplements or making changes to your regimen.