centuries, acupuncturethe subcutaneous insertion of
needles in certain parts of (mostly) the human bodyhas
been practiced for diagnostic as well as remedial purposes.
Plenty of reports have noted the surprising effects
of acupuncture on many types of diseases or discomforts.
It should be stressed, however, that these reports are
normally anecdotal, often collections of single cases,
and are rarely based on strict scientific investigations
such as double-blind tests, etc. These reports also
fail to explain why and how acupuncture works (if it
Volumes are written about acupuncture practices relative
to various ailments. Almost all of these treatises talk
about meridians and acupuncture points, but very little
can be found in terms of explaining scientifically why
the insertion of a needle in one of these points should
have any kind of effect.
For the sake of the argument, assume that meridians
and acupuncture points are scientific facts and that
they represent especially sensitive zones of the body.
Is there then a way that a needle in such a point might
interact physically with the environment?
It has been suggested that a flow of unipolar atmospheric
ions plating out on the skin of a grounded person gives
rise to effects similar to those claimed to be associated
with acupuncture.1 If it is assumed that
a static electric field exists around the person, the
needle will distort the field (see Figure 1) and attract
(more) atmospheric ions to the person. The ions will
be neutralized when arriving at the needle, resulting
in a current through the body, possibly along meridians
or other paths of low resistance.
I decided to demonstrate this effect. However, the currents
involved in these processes are very low (on the order
of 1014 A, or even lower). Therefore,
it would have been extremely difficult to measure directly
the current flowing to a person caused by an acupuncture
needle. Even a person's unavoidable movements (e.g., breathing)
would interfere negatively with the measurements.
It was decided to try to simulate the situation shown
in Figure 1. The setup used for the simulation is shown
in Figure 2. Between two metallic field plates (0.35
0.35 m2) at a distance d, an electric field
is established. One plate was connected to a high-voltage
supply; the other plate was virtually grounded through
an electrometer. The field plates were placed about
0.5 m above the floor in an approximately 70-m3
room. The electrometer was connected to a recorder because
the presence of persons in the room during measurements
would interfere with the results.
If the voltage difference between the field plates is
V, an electric field exists between the plates with
the mean value of
the experiments performed in this investigation, the
voltage V was negative; i.e., negative ions were driven
toward the plate connected to the electrometer (and
positive ions in the opposite direction).
A series of measurements were performed where the voltage
V and the distance d were varied. For each value of
V and d (i.e., for a given field strength E, Equation
1), the mean value of the current I to the electrometer
was calculated from the charge q integrated over the
measuring time t by
In the first series of measurements, both field plates
were planar and even. To simulate the effect of an acupuncture
needle, a sewing needle was mounted in a hole in the
field plate connected to the electrometer. Figure 3
illustrates the difference between the two situations.
Figure 3a shows the homogeneous field with no needle,
and Figure 3b shows the distorted field around the needle.
Figure 4 shows an example of the relationship between
the current I and the mean field strength E with and
without a needle. It appears that the relationship is
linear with the inclinations.
1. Electric field around an acupuncture needle.
3 and 4 indicate that the presence of the needle causes
25% more ions to collect on the metal plate. The results
shown in Figure 4 are typical of the relationship of
the values with and without a needle. A series of 25
sets of measurements were performed. The actual currents
varied considerably from day to day, and even within
the same day. These fluctuations are due to variations
in the natural ion concentrations caused primarily by
changes in the aerosol density. To a lesser degree,
variations in the ion production rate also cause fluctuations.
However, when the measurements were performed in a stable
period (at least 56 hours), the results were consistent
with the needle giving rise to an increase in the current
relationship expressed in Equation 3 obviously reflects
the concentration and mobility of the negative ions
in the room. If the area of the collecting plate is
S, the relationship can be expressed as
2. Experimental setup without acupuncture needle.
i is the current density, i.e., current per unit area
m2). As the area S is 0.35 x
0.35 m2, Equations 3 and 5 lead to
The relationship between field strength and resulting
current density is Ohm's law (in differential form)
is the (polar) conductivity. Equation 7 can also be
From Equations 6 and 8, Equation 9 can be derived as
can be written as
where e is the electronic charge, and n and k are the
concentration and mobility, respectively (in this case,
the negative ions). As e = 1.6 x
1019C and k = 1.8 x
Equations 9 and 10 lead to
3. Electric field without and with needle.
4. Current I as a function of the mean field strength
It has been demonstrated that a conductive needle protruding
from a conductive surface in an electric field will
cause more ions to arrive at the surface than would
be the case if the needle were not there. In addition,
it was also demonstrated that it is possible from the
measurements described to deduce the polar conductivity
and concentration of (in this case) the negative atmospheric
In the introduction, it was suggested that the effect
of an acupuncture treatment could be partly explained
by weak currents through the body being enhanced by
the acupuncture needles distorting an electric field
and attracting more atmospheric ions. It should be stressed
that this explanation presupposes the existence of an
electric field around the person being treated. This
explanation also assumes that the person is sufficiently
grounded. There are situations in which a person would
be in a field-free environment, and thus the effect
described above would not take place. On the contrary,
however, modern buildings often have surprisingly high
field strengths from charged insulative materials.
This article is not intended to explain whether or how
acupuncture works. Rather, it has presented some ideas
about a possible relationship between the effect of acupuncture
needles and the number of ions arriving to a body in an
electric field. The number of ions attracted to single
needles by the action of an incidental field is extremely
low and so are the resulting currents. Therefore, instead
of using needles inserted in discrete (acupuncture) points,
a more-effective method may be to spray the skin with
an abundance of unipolar ions. The charge from the neutralized
ions would find its own way through the body along the
paths where the current has the greatest effect. That
method is basically the idea behind the project described
in last issue's column. More studies are under way. In
about a year, the findings should confirm whether the
theory is sound.
1. Niels Jonassen, "Are Ions Good for You?" in Mr.
Static, Compliance Engineering 19, no. 7 (2002)
Niels Jonassen, MSc, DSc, worked for
40 years at the Technical University of Denmark, where
he conducted classes in electromagnetism, static and atmospheric
electricity, airborne radioactivity, and indoor climate.
After retiring, he divided his time among the
laboratory, his home, and Thailand, writing on static
electricity topics and pursuing cooking classes. He passed away in 2006.