There are now a number of websites making unsubstantiated claims that grounding(earthing) therapy is nothing more than “snake oil” or pseudo-science.
Hоwеvеr, multidiѕсiрlinаrу rеѕеаrсh оvеr the раѕt 15 уеаrѕ ѕignifiсаntlу ѕuggеѕtѕ otherwise and has dеmоnѕtrаtеd thаt grоunding (Eаrthing) thе humаn bоdу to Eаrth’ѕ ѕurfасе charge gеnеrаtеѕ multiрlе bеnеfiсiаl рhуѕiоlоgiсаl еffесtѕ.
Earthing skeptics like to try and claim that grounding has no effect on the human body, however the current research has found many measurable physiological effects of grounding using state of the art equipment from improved HRV(heart rate variability) to lowered inflammatory biomarkers.
I thought it would be a good idea to compile the small pool of preliminary studies on grounding and highlight just exactly what the scientific literature is claiming when it comes to earthing and its potential health benefits.
BALANCING THE (ANS) AUTONOMIC NERVOUS SYSTEM
Earthing & Grounding Autonomic Nervous System StudiesOne of the most exciting potential therapeutic benefits that earthing has demonstrated in studies is the ability of grounding to balance the ANS (Autonomic Nervous System).
A number of double-blind studies have now shown a shift in ANS balance upon earthing, specifically a rapid activation of the parasympathetic nervous system, coupled with a resulting deactivation of sympathetic activity.
As a result earthing may hold huge potential as a treatment for everything from general stress to dysautonomia/POTS and many other health conditions that involve the role of the autonomic nervous system.
As an individual who suffers from dysautonomia and heightened sympathetic tone due to CFS, I would say the earthing bedsheet is one of the most powerful alternative therapies I have tried to balance the ANS to date.
No medicinal herb, pharmaceutical drug, meditation or exercise has even come close to the powerful effect that earthing has had on improving my dysautonomia symptoms, most specifically the orthostatic intolerance issues and the excessive heightened sympathetic tone.
Upon lying on the earthing bedsheet you can almost instantaneously feel the sympathetic “fight or flight” stress response being attenuated, and a nice relaxing effect from the activation of the parasympathetic nervous system.
A multiparameter double-blind study was designed to reproduce and expand on previous electrophysiological and physiological parameters measured immediately after grounding with an improved methodology and state-of-the-art equipment.
The study found that grounding resulted in an immediate decrease in SC(skin conductance), which indicates a rapid activation of the parasympathetic nervous system and corresponding deactivation of the sympathetic nervous system.
The immediate increase in SC at cessation of grounding indicates an opposite effect. Increased RR(respiratory rate), stabilization of BO(blood oxygenation), and slight rise in heart rate suggest the start of a metabolic healing response necessitating an increase in oxygen consumption. 
IMPROVED HRV(HEART RATE VARIABILITY)
Earthing & Improved HRV (Heart Rate Variability) StudiesThe rapid change in skin conductance reported in an earlier study led to the hypothesis that grounding may also improve heart rate variability (HRV), a measurement of the heart’s response to ANS regulation.
HRV imbalance reflecting autonomic dysfunction and the severity of progression of coronary artery disease has been repeatedly demonstrated in clinical investigations.
A double-blind study published in 2011 with 27 participants found that:
During the grounded sessions, participants had statistically significant improvements in HRV that went way beyond basic relaxation results (which were shown by the nongrounded sessions).
Since improved HRV is a significant positive indicator on cardiovascular status, it is suggested that simple grounding techniques be utilized as a basic integrative strategy in supporting the cardiovascular system, especially under situations of heightened autonomic tone when the sympathetic nervous system is more activated than the parasympathetic nervous system.
In patients who experience anxiety, emotional stress, panic, fear, and/or symptoms of autonomic dystonia, including headaches, cardiac palpitations, and dizziness, grounding could be a very realistic therapy.
These patients may see positive effects most likely within 20 to 30 minutes and in almost all cases in 40 minutes.
Negative emotions such as panic, depression, anxiety, and hostility have all demonstrated reduced HRV. Grounding has the potential to help support HRV, reduce excessive sympathetic overdrive, balance the ANS, and, thus, attenuate the stress response.
This has important prognostic considerations especially because an association between depression and increased risk of cardiovascular events has been repeatedly observed in both the healthy population and patients with established cardiovascular disease. 
GROUNDING MAY LOWER BLOOD PRESSURE
Grounding Lower Blood Pressure Hypetension StudyThere are many anecdotal reports of individuals using earthing(grounding) to lower high blood pressure (hypertension).
A pilot case history series was undertaken with hypertensive patients in a single physician cardiology practice and the results published in 2018.
All 10 patient measurements were found to be significantly improved at the end of the trial period, and some, well before the end. Systolic levels decreased during this time, ranging individually from 8.6% to 22.7%, with an average decrease of 14.3%.
The study concluded:
This is the first known study measuring the influence of grounding the body on hypertension. The results indicate that grounding appears to be a safe BP-reducing therapy warranting further research. 
CHRONIC INFLAMMATION, PAIN REDUCTION & DOMS(DELAYED MUSCLE)
Earthing & Inflammation, Autoimmune Disease & DOMS StudyPreliminary research has suggested that grounding may produce multiple intriguing effects on physiology and health, relating to inflammation, immune responses, wound healing, and prevention and treatment of chronic inflammatory and autoimmune diseases.
Anecdotally there are a number of reports of individuals finding improvement in chronic pain disorders, fibromyalgia, arthritis and the likes of inflammatory related autoimmune diseases with grounding/earthing therapy.
Specifically, grounding an organism produces measurable differences in the concentrations of white blood cells, cytokines, and other molecules involved in the inflammatory response.
Grounding reduces pain and alters the numbers of circulating neutrophils and lymphocytes, and also affects various circulating chemical factors related to inflammation. 
Pain reduction from sleeping grounded has been confirmed in a controlled study on DOMS. Earthing is the first intervention known to speed recovery from DOMS.
A pilot study published in 2010 studied the effects of grounding on delayed-onset muscle soreness (DOMS and concluded:
Grounding the body to the earth alters measures of immune system activity and pain. Since this is the first intervention that appears to speed recovery from DOMS, the pilot provides a basis for a larger study. 
SLEEP DYSFUNCTION & NORMALIZING CORTISOL/CIRCADIAN RHYTHM
Earthing Sleep, Cortisol StudyOne of the most common health benefits that individuals report from earthing/grounding is improved sleep and increased energy levels.
A small pilot study found that earthing may help to improve aspects of sleep quality and to restore normal day-night cortisol patterns.
This may be of huge benefit to individuals with stress disorders and the likes of hypothalamic-pituitary-adrenal dysregulation, who typically have disturbed cortisol levels.
A pilot study evaluated diurnal rhythms in cortisol correlated with changes in sleep, pain, and stress (anxiety, depression, and irritability), as monitored by subjective reporting.
Twelve subjects with complaints of sleep dysfunction, pain, and stress were grounded to Earth during sleep in their own beds using a conductive mattress pad for 8 weeks.
Subjective symptoms of sleep dysfunction, pain, and stress were reported daily throughout the 8-week test period. The majority of subjects with high- to out-of-range nighttime secretion levels experienced improvements by sleeping grounded. This is demonstrated by the restoration of normal day-night cortisol secretion profiles.
Eleven of 12 participants reported falling asleep more quickly, and all 12 reported waking up fewer times at night. Grounding the body at night during sleep also appears to positively affect morning fatigue levels, daytime energy, and nighttime pain levels. 
Overall, whilst the studies are small and only preliminary, it appears from the mounting scientific evidence that earthing (grounding) has multiple measurable physiological effects on the human body.
This is a far cry from the physics and anti alternative medicine bloggers who are trying to incorrectly claim that earthing has NO effect on the human body and/or any research supporting its health benefits, which as shown above is not true.