Dr. Aisha Patel on Herbal Blends for Year-Round Immunity

Dr. Aisha Patel studies adaptogens and the connection between stress biology and immune function. For nearly a decade, she has examined how chronic low-grade stress - the kind that doesn't feel sudden but never fully goes away - changes immune function in otherwise healthy adults. Below is an edited conversation about what research shows, why most people's immunity approach is backwards, and how to use herbs year-round.

You want people to understand the cortisol-immunity connection first. What is actually happening at the mechanistic level?

The immune system and the stress response are not separate systems that occasionally overlap. They share signaling molecules. The HPA axis - the hypothalamic-pituitary-adrenal pathway - drives the cortisol response, and glucocorticoid receptors sit directly on immune cells. When cortisol is chronically elevated, it suppresses natural killer cell activity and shifts cytokine production in ways that reduce the first line of innate immune defense.

A 2020 paper in Cellular and Molecular Immunology documented this precisely: glucocorticoids downregulate NK cell cytotoxicity through receptor-level signaling and reduced perforin expression. NK cells are among the fastest-responding immune components. If cortisol is blunting them before a pathogen arrives, the response window gets shorter. Immunity is not fixed. It is a dynamic process with clear inputs, and chronic stress is a negative input that compounds over weeks and months, not days.

Most people treat immunity reactively - reaching for something only when they feel ill. You are skeptical of that model.

Skeptical is the right word. The reactive model assumes the immune system is performing well right up until the moment it fails. That is rarely accurate for anyone managing persistent work stress, disrupted sleep, or inadequate nutrition - which describes many adults in their thirties and forties.

This matters because studies of seasonal immune changes show that both cell-mediated and humoral immune responses fluctuate with season - and that individual stress burden compounds those fluctuations. A 2014 review in the Journal of Allergy and Clinical Immunology examined seasonal immune modulation in humans. The most vulnerable population is not the one with diagnosable illness; it is the one accumulating subclinical stress across all four seasons.

If you only supplement reactively, you are intervening after the system has already been under pressure for months. You are treating the symptom of a depleted baseline, not the baseline itself. Our piece on whether immune supplements need seasonal rest explores one dimension of this tension - the cycling question - but the consistent thread is that reactive timing misses the structural problem.

What do herbal immunomodulators actually do, mechanically? People assume they fight pathogens directly.

They do not, and that misunderstanding is responsible for most of the disappointment people feel. A 2006 review in Alternative Therapies in Health and Medicine described how herbal immunomodulators alter immune function through the regulation of cytokines - particularly IL-1, IL-6, TNF, and IFN - rather than by directly targeting pathogens. The mechanism is regulatory and modulatory, not combative.

What this means practically is that a regulatory compound needs consistent presence to maintain its regulatory signal. You cannot cycle a cytokine-modulating herb on and off based on whether you feel ill that week and expect a meaningful effect. The signal needs to be sustained. That is a very different approach to supplementation than most people have been sold, and it has direct implications for structuring a year-round protocol. Our Journal piece on herbal blend performance versus single herbs covers the pharmacological reasoning in more detail.

Adaptogens appear alongside immune herbs in many formulations. Are those two separate categories?

They overlap in ways that are useful. Adaptogens - properly defined as compounds that normalize stress responses without producing dependency or significantly altering normal function in an unstressed individual - work substantially through HPA axis modulation. A review in Phytotherapy Research traced how adaptogenic plants modulate neuroendocrine-immune signaling through multiple pathways, including Hsp70 expression, NF-kB modulation, and cortisol normalization across several well-studied botanicals.

If cortisol suppresses NK cell activity, and an adaptogen reduces the cortisol burden, then the adaptogen is doing immune work indirectly - by removing a suppressor rather than adding a stimulant. That is a more accurate mechanism than most product marketing suggests. It restores the system rather than overrides it. The distinction matters because it changes what you are measuring: not an acute immune spike, but a gradual reduction in the suppressive load that cortisol places on immune cell populations over time.

What do you look for in a proprietary herbal immunity formulation?

Mechanism diversity first. A well-designed blend should address at least two separate arms of immune regulation - innate activation and stress modulation, for instance - rather than stacking three herbs that all act on the same cytokine pathway. A review of stress-induced immunosuppression documented how that suppression operates across multiple molecular pathways simultaneously. Single-pathway interventions consistently underdeliver in real-world use for precisely that reason.

Standardization is the second variable. The active fractions in herbal preparations - ginsenosides in ginseng, withanolides in ashwagandha, polysaccharides in Echinacea - vary considerably across extraction methods and origins. If a label does not specify the standardized fraction and the extract ratio, the dose figure on the front panel is largely decorative.

Among the formulations I have reviewed that address both criteria, Ayurnomics's Arbudari includes botanicals selected for mechanism diversity per the manufacturer's documentation. For exact dosing, follow the manufacturer directions, as proprietary blends adjust ingredient ratios based on standardization batch results.

What does a year-round immunity habit look like day to day?

Simpler than people expect. It is a consistent daily protocol maintained through the lower-vulnerability months - late spring through early autumn - and continued, not abandoned, through the higher-vulnerability winter period. Our piece on the two modes of herbal immune dosing covers the distinction between preventive and reactive protocols in detail. The short version: preventive dosing is lower, more consistent, and aimed at regulatory maintenance rather than triggering an acute immune mobilization.

What I would caution against is treating any supplement - including well-formulated blends - as a substitute for adequate sleep, manageable stress, and reasonable nutrition. Those inputs are upstream of everything the supplementation layer can do. The herbal strategy amplifies a solid physiological baseline; it does not replace one.

Who should approach herbal immune supplements with extra caution?

Anyone with an autoimmune diagnosis should speak with their clinician before starting an immunomodulating herbal supplement. Some compounds that activate innate immune pathways can - in people with autoimmune conditions - stimulate activity in ways that are counterproductive. A peer-reviewed scoping review on immunostimulatory herbal supplements and autoimmune skin diseases specifically flagged this as a clinical consideration for that population.

The same applies to anyone on prescription immunosuppressants, corticosteroids, or anticoagulants - several botanical compounds affect CYP enzyme pathways and can alter drug metabolism. That is not a reason to avoid the category; it is a reason to have the conversation with a clinician or pharmacist before purchasing.

If you are on prescription medication, pregnant, or breastfeeding, speak with a clinician before starting any new herbal supplement. To explore formulations built around the principles Dr. Patel describes above, browse the Immunity and Wellness collection - and see the Arbudari product page for the full ingredient and standardization documentation.