insights

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A healthy innate immune system is both a detective, scanning the body for potentially threatening invaders, and a first responder, thwarting pathogens and prompting repair. Innate immunity first appeared 750 million years ago and has been remarkably conserved throughout evolution,¹ and it is now understood to be the gatekeeper for coordinating the body’s entire immune response.² How can diet and lifestyle modifications support the health of this critical system?

Cells of the innate immune system detect the presence of many potential pathogens using pattern recognition receptors that recognize classes of molecules common to many foreign types of bacteria, fungi, and/or viruses.³ Each organ in the body uses unique sets of cells and molecules that orchestrate regional innate immunity.¹ The gut microbiota and the innate immune system have a reciprocal relationship, with any microbial disruption or dysbiosis potentially altering the innate immune response and vice versa.^4,5

Deregulated innate immunity is increasingly common and has been shown to contribute to a wide range of diseases, including:

• Intestinal diseases such as irritable bowel syndrome and other chronic inflammatory intestinal diseases.^6,7
• Autoimmune diseases, including type 1 diabetes and rheumatoid arthritis.^8,9
• Neurodegenerative disorders such as Alzheimer’s disease, amyotrophic lateral sclerosis, Parkinson’s disease, and Huntington’s disease.¹⁰
• Chronic obstructive pulmonary disease.^11,12

Over the last decade, a growing body of knowledge about the workings of innate immunity has been translated into clinical practice. In the following video, Kara Fitzgerald, ND, IFMCP, outlines foundational interventions for improved immune health and those immunomodulators she commonly uses with patients.

Nutritional Support and Exercise Benefits

Curcumin is a natural anti-inflammatory, and studies suggest that in humans, one aspect of the positive effects of curcumin on health could be related to its ability to enhance IL-10-mediated effects.¹³ IL-10 is an anti-inflammatory and immunosuppressive cytokine that is produced by both innate and adaptive immune cells; IL-10 deregulation plays a role in a number of inflammatory diseases associated with an unhealthy innate immune system.¹³ In addition, recent reviews have suggested that while the mechanism is unclear, phytochemicals, including curcumin, resveratrol, and sulforaphane, inhibit NLRP3 (nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing 3) inflammasome activity;^14,15 this protein initiates the release of proinflammatory cytokines as part of the innate immune system and has been implicated in a wide range of chronic diseases.¹⁶

A 2018 study suggests that environmental stress may induce changes in the innate immune system, causing dysfunction.¹⁷ Nutrition, including the use of polyphenols like curcumin, may play an essential role in immunity by altering proinflammatory cytokine synthesis, immune cell regulation, and gene expression.¹⁷ Studies have shown that curcumin has an inhibitory effect on the toll-like receptor pathway (TLR) signaling pathways, namely in TLR-2 and TLR-4 activation,^18,19 suggesting its role in reducing overall inflammatory burden, particularly for autoimmune and rheumatic diseases.^19,20

Natural antioxidants may reduce inflammation and oxidative stress, thereby contributing to a more robust immune system and response.¹⁸ Antioxidant nutrients such as vitamin E, vitamin C, β-carotene, selenium, copper, iron, and zinc improve different immune functions and play a protective role in the event of an infection.^21-23

Additionally, evidence suggests that exercise has a profound effect on the functioning of the immune system.^24,25 It is generally accepted that prolonged periods of intensive exercise training can depress immunity, while regular, moderate-intensity exercise is beneficial.²⁴ In 2018, research found that a high-intensity interval walking protocol in older adults with stable rheumatoid arthritis was associated with reduced disease activity, improved cardiovascular fitness, and improved innate immune functions, indicative of reduced infection risk and inflammatory potential.²⁶ Another recent study provides evidence to suggest that cytotoxic T cells become transiently reductive (stressed) in healthy individuals following a single bout of cycling.²⁷

What other dietary and lifestyle changes can affect immune modulation? Learn more about the physiology and pathophysiology associated with immune dysregulation and their associations with systemic disease in IFM’s Immune Advanced Practice Module (APM). The Immune APM provides clinicians with an in-depth understanding of underlying immune mechanisms and effective interventions to support and balance immune function.

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Immunology and the Microbiome

Gut Health and the Immune Response

References

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