Chiropractic Care and the Nervous System: What Emerging Research Is Showing

New Research Shows Chiropractic Care May Influence Inflammation, Stress Hormones and Neuroplasticity

Many people who come to see us at Guildford Chiropractic Centre describe experiences that go beyond simple pain relief. They talk about feeling “lighter,” “more balanced,” or “just better all over” after a course of care — sensations that suggest something more than just joint or muscle movement.

Until recently, there’s been good clinical evidence that chiropractic care helps with pain and movement. But the question of why people often feel better — and whether there are measurable physiological effects beyond symptom relief — has been harder to answer.

Now, an exciting new study is beginning to shed light on this very topic.

What the Research Shows

A pragmatic randomised controlled trial published in PLOS One in December 2025 investigated how 12 weeks of chiropractic spinal adjustments influenced a range of biological markers in adults with subclinical spinal pain. These included:

• Brain-derived neurotrophic factor (BDNF) — a protein linked to neuroplasticity and nervous system adaptability

• Cortisol — a hormone involved in stress regulation

• Inflammatory cytokines such as interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α)

  
  

The study found that after 12 weeks of chiropractic care:

• Blood levels of BDNF were higher in the chiropractic group compared with the sham group, suggesting enhanced neuroplastic signalling.

• IL-6 levels were also higher — an indicator related to inflammatory and regenerative processes.

• TNF-α levels were lower — a sign of regulatory effects on systemic inflammation.

• Changes in cortisol and other immune markers hinted at effects on stress-related physiology.

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You can read the full open-access paper here:🔗 Amjad I et al. The effects of 12 weeks of chiropractic spinal adjustments on physiological biomarkers in adults — PLOS One (2025)

Why This Matters — and Why It’s Just the Beginning

This study doesn’t prove that chiropractic adjustments are a cure for inflammation or stress — that would be far too bold a claim. But what it does show is something meaningful:

1. There are measurable changes inside the body associated with a course of chiropractic care.

2. These changes involve systems (nervous, immune, stress) that are wider than just “pain pathways.”

3. The findings support the idea that chiropractic care may influence the body’s regulatory and adaptive mechanisms in ways researchers can now begin to quantify.

That’s a big deal — not because it “proves everything,” but because it points toward mechanisms that science has only just begun to measure.

How This Connects to the “Feel Good” People Often Report

What about the sensations patients describe — that feeling of improved ease, clarity or regulation after an adjustment?

This new research doesn’t directly measure subjective feelings — it looks at biological signals that may underlie them. For example:

• BDNF is sometimes described as “fertiliser for the nervous system,” because higher levels are linked to neuroplasticity, adaptability and recovery.

• Cortisol shifts may reflect changes in how the body responds to stress.

• Inflammatory markers like IL-6 and TNF-α are deeply involved in how tissues respond to stress, repair and adapt over time.

  
  

Taken together, these kinds of changes help explain why relief after care can feel systemic, not just local — because they involve nervous system regulation, immune balance, and hormonal signalling.

Why It’s Hard to Study These Effects

There are a few reasons this science is only now emerging:

📌 The systems involved are complex

The nervous system, stress responses and immune signalling are interlinked and dynamic. That makes them hard to measure reliably, especially over time.

📌 “Sham” care is difficult to design

In drug trials, pills can be exactly mimicked. In manual therapy trials, creating a truly inert sham that doesn’t trigger some physiological response is much harder. That blurs the difference between groups and makes clean comparisons challenging.

📌 Outcomes are subtle and long-term

The effects being studied aren’t always dramatic or immediate — they’re often small shifts in regulation over weeks or months, which require careful long-term follow-up and large sample sizes to detect.

Because of these challenges, this study is exciting not because it is conclusive, but because it opens the door to deeper exploration.

A Thoughtful Perspective on Wellness

For decades, many in the chiropractic profession have talked about care supporting wellbeing, balance and resilience, not just pain relief. This study doesn’t “prove” that in the broad sense — but it does show measurable changes in physiological systems associated with adaptation and regulation, and that’s a meaningful start.

Rather than creating headlines that claim miracles, this research invites curiosity: science is beginning to map pathways that may help explain what clinicians and patients have observed for years. As research methods refine and larger, longer studies are done, we’re likely to learn much more about how manual care interacts with the body’s broader systems.

For now, studies like this give us reason to be thoughtful and hopeful — not because the science is finished, but because it’s finally asking the right questions.

📌 Reference

Amjad I, Niazi IK, Kumari N, Ghani U, Rashid U, Duarte FCK, et al. The effects of 12 weeks of chiropractic spinal adjustments on physiological biomarkers in adults: A pragmatic randomised controlled trial. PLOS One. 2025;20(12):e0338730.🔗 https://doi.org/10.1371/journal.pone.0338730