Chiropractic Spinal Adjustments Have Positive Anxiety and Depression Outcomes

Anxiety and depression are types of mood disorders. Among other things, depression causes feelings of sadness, hopelessness and reduced energy. Anxiety creates feelings of nervousness, worry and/or dread. Although the two conditions are different, you can have both at the same time. Agitation and restlessness can be symptoms of both depression and anxiety.¹

During 2022, about one in five adults ages 18 and older experienced any symptoms of anxiety (18.2%) or symptoms of depression (21.4%) in the previous two weeks. The severity of symptoms differed by sociodemographic and geographic characteristics. The percentages of adults with mild, moderate, or severe symptoms of both anxiety and depression were highest among adults ages 18–29 and decreased with age; and were higher among women than men.²

When considering anxiety and depression, multiple brainwave patterns were studied to see a correlation with the amplitude of each wave. Increased alpha wave activity is generally associated with reduced anxiety, improved relaxation, and decreased physiological arousal. Alpha training has been used in neurofeedback to calm the mind and reduce anxious thoughts.³ The frontal lobe, parietal lobe, occipital lobe⁴ and temporal lobe were found to have much lower alpha waves in the depression group compared to the normal group.⁵

Chiropractic vs. Non-Chiropractic Spinal Adjustments

When studying the neurophysiology of a chiropractic spinal adjustment (CSA) and its relationship to anxiety and depression, mechanisms are critical. Therefore, one cannot interchange a CSA with a physical therapy manipulation or mobilization, as the mechanism and neurobiochemical processes are different and render different results.

The arbiter and ultimate test between the CSA and spinal manipulation is the central segmental motor control (CSMC) changes that occur as sequela to that treatment. The CSMC changes have been evidenced (a topic for another discussion) and are easily defined as central nervous system changes that affect the motor and other functions of the brain afferently. The core of the difference is where the thrust is directed.

Haavik, et al. (2021), reported, “It is possible to direct a thrust at any spinal segment, regardless of whether it is dysfunctional or not. Therefore, for the purposes of this review, if a thrust is directed at a spinal segment that has not been examined and identified as having clinical indicators of dysfunction, it will be referred to as spinal manipulation. In contrast, a thrust directed at a dysfunctional vertebral motion segment will be referred to as a spinal adjustment. This distinction is important, as adjustments are likely to have different physiological consequences compared to thrusting at or manipulating a vertebral segment that has no signs of motor control dysfunction.”⁶

Outcomes: Chiropractic Spinal Adjustments and Neuroplastic Changes

The key is determining the dysfunctional segments that make neuroplastic changes based on outcomes. In those dysfunctional segments, the high-velocity, low-amplitude thrust, or chiropractic spinal adjustment (CSA/HVLA), must be directed or you will be manipulating and not realize the best outcomes.

In determining outcomes, a CSA/HVLA thrust in deep abdominal muscular activation was 38.4% better than manipulation. Six months later, 19% of that additional muscular activation was retained.

A CSA/HVLA thrust increased the H-reflex and V-wave (neurological feed to the central nervous system) by 16% without muscular fatigue. The control and manipulation group had no changes in amplitude, and the muscle fatigued much earlier. Maximum voluntary contractions of the jaw increased by 55% to 60% with CSA/HVLA thrusts only after one adjustment. Maximum voluntary contractions increased by 64.2% in chronic stroke survivors with CSA/HVLA only after one adjustment. A CSA/HVLA spinal adjustment increases motor evoked potentials by 54.5% in the upper-limb muscles and 44.6% in the lower limb muscles. A CSA/HVLA had a 16.76% change in the neurophysiological change in the 30N SEP (brain impulses). It changed brain functioning.^7-10

Haavik, et al., also performed neurophysiological assessments post-chiropractic spinal adjustments, which revealed, based on electroencephalogram (EEG) and somatosensory evoked potentials (SEPs), that alpha bands in the brain increased significantly. They found this persisted when retested after four weeks. The control groups showed no changes.¹¹

Haavik, et al., also reported it has long been known that a chiropractic spinal adjustment creates neuroplasticity (the brain's ability to change and adapt) in the primary somatosensory cortex, primary motor cortex, prefrontal cortex, and cerebellum. These cortical regions directly affect the Default Mode Network, a system of interconnected brain areas that become more active when a person is not focused on external stimuli or engaged in a specific task, and is directly related to sleep.

Anxiety / Depression Medications: Long-Term Side Effects

Anxiety and depression medications, particularly selective serotonin reuptake inhibitors (SSRIs), benzodiazepines and other antidepressants, have varying effects on alpha brainwaves (8-12 Hz), which are typically associated with a relaxed, yet alert state.¹² However the potential long-term side effects are numerous:

Selective Serotonin Reuptake Inhibitors (SSRIs)¹³: Common long-term side effects:

• Emotional blunting or reduced emotional reactivity
• Sexual dysfunction (can persist even after discontinuation, known as PSSD – post-SSRI sexual dysfunction)
• Weight gain
• Sleep disturbances
• Increased risk of gastrointestinal bleeding
• Withdrawal symptoms upon discontinuation (even after long-term use)
• Possible increased risk of bone fractures and osteoporosis
• Emotional numbing or apathy

Benzodiazepines¹⁴: Common long-term side effects:

• Cognitive impairment (e.g., memory loss, slowed thinking)
• Dependency and tolerance
• Withdrawal syndrome (can be severe and long-lasting)
• Emotional blunting
• Motor impairment
• Increased risk of dementia with prolonged use in elderly patients
• Depression and worsening of mood disorders in some users

Antidepressants (e.g., SNRIs, TCAs, MAOIs)¹⁵

SNRIs (Serotonin-Norepinephrine Reuptake Inhibitors)

• Similar side effects to SSRIs with additional risk of hypertension and sweating
• Long-term risk of withdrawal symptoms (especially with venlafaxine)

TCAs (Tricyclic Antidepressants)

• Anticholinergic effects (dry mouth, constipation, urinary retention)
• Cardiovascular risks (arrhythmias, hypotension)
• Weight gain and sedation
• Cognitive decline in older adults

MAOIs (Monoamine Oxidase Inhibitors)

• Dietary restrictions required (risk of hypertensive crisis)
• Sleep disturbances
• Weight gain
• Potential for severe interactions with other drugs

Clinical Take-Home Points

The current literature confirms the safety of chiropractic care. In 2023, data from 960,140 patients revealed an extremely low adverse event rate of 0.00021%, with all reported outcomes being minor in nature. The use of chiropractic as a first-line treatment to manage anxiety and depression could help, while avoiding long-term side effects. When indicated, medication is useful, but common sense dictates drugless first, drugs second, and surgery last.

References

1. Anxiety vs. Depression. WebMD, 2025. Read Here
2. National Health Interview Survey, 2022 (survey description). National Center for Health Statistics, 2023. Read Here
3. Hammond D. Neurofeedback treatment of depression and anxiety. J Adult Develop, 2005;12(2-3):131-137.
4. Wong M-Y, et al. “Brainwave Patterns and Anxiety Symptoms Among Young Adult Females: An Exploratory Study." 2024 IEEE 14^th International Conference on Control System, Computing and Engineering (ICCSCE).
5. Kan DPX, et al. "Decrease Alpha Waves in Depression: An Electroencephalogram (EEG) Study." 2015 International Conference on BioSignal Analysis, Processing and Systems (ICBAPS).
6. Haavik H, et al. The contemporary model of vertebral column joint dysfunction and impact of high-velocity, low-amplitude controlled vertebral thrusts on neuromuscular function. Euro J Appl Physiol, 2021;121(10):2675-2720.
7. Haavik-Taylor H, Murphy B. Transient modulation of intracortical inhibition following spinal manipulation. Chiro J Australia, 20007b;37:106.
8. Haavik H, et al. Impact of spinal manipulation on cortical drive to upper and lower limb muscles. Brain Sci, 2017;7:2.
9. Marshall P, et al. The effect of sacroiliac joint manipulation on feed-forward activation times of the deep abdominal musculature. J Manipulative Physiol Ther, 2006;29:196-202.
10. Haavik H, et al., 2021: Op Cit.
11. Ibid.
12. Bruder GE, et al. Electroencephalographic alpha measures predict therapeutic response to a selective serotonin reuptake inhibitor antidepressant: pre- and post-treatment findings. Biological Psych, 2008;63(12):1171-1177.
13. Fava GA, et al. The potential role of iatrogenic comorbidity in the interaction between pharmacotherapy and psychotherapy in anxiety disorders. CNS Drugs, 2014;28(5):405-417.
14. Barker MJ, et al. Cognitive effects of long-term benzodiazepine use: a meta-analysis. CNS Drugs, 2004;18(1):37-48.
15. Byerly MJ, et al. Safety and tolerability of antidepressants: a review. Psychiatric Clinics North Am, 2008;31(1):15-30.