Herbs and Essential oils -
the differences in action and the errors in aromatherapy

By Martin Watt

The following three old newsgroup emails have been put into this
article because aromatherapists are still not being educated on these
vital issues. Indeed leading course providers and oil suppliers continue
to promote essential oils based on facts gleaned from herbal medicine.

1) Date Aug. 1998
To: aromatherapy@idma.com

Herbs v oils
Some thoughts for Lowana and others:

Where the actions of a herb do correlate with the actions of the same plants oil
this is frequently following the observed effects from ORAL administration of
the oil and or herb. This is where aromatherapy authors and teachers make big
mistakes in assuming similar effects from external application.

The aroma has rarely got much to do with the major components in most oils,
indeed the characteristic fragrance of essential oils is often due to compounds
occurring at only a few parts per million and occasionally only a few parts per
billion. Therefore if one presumes that many of the effects of aromatherapy
are due to the smell of the essential oils and their effects on the brain, then
this has little to do with the major constituents.

In addition to this, we have the classic scientific error of attributing effects and
side effects to only one or two chemicals out of perhaps hundreds in a given oil
or herb. This concept is fraught with error, not least of which is because new
novel compounds with unknown actions are still being found in our most
commonly analysed plants.

One of your examples - aniseed is a good one to look at. Aromatherapists say
applying this oil to the breasts promotes lactation. I say nonsense!!

The traditional method reputed to promote lactation was/is the consumption of
the whole seed. Seeds contain vitamins, minerals, protein, carbohydrate, etc.,
all necessary to produce milk. The whole seed may contain other unknown
compounds that affect the hormonal system. However if trans anethol is a
hormone precursor in vivo, is still very much open to debate within the
scientific community. I believe it is not, all tests conducted so far are

Don't get me wrong, of course some of the actions of certain herbs do
correlate with their content of essential oil, but the whole thing is extremely
complex and always depends on the mode of use of the particular extract.
Since I am convinced that aromatherapy does not work via skin absorption of
the essential oils, then the observed emotional effects are much more likely to
be due to trace compounds.

That is why so much aromatherapy teaching on chemistry is wrong. Again I
have to return to the French system promoted by Franchomme, and Penoel. It
is the methods advocated by them that permeates most aromatherapy
teaching, but these theoretical models are flawed in the extreme – Please
note the date of this post 1998
and see other articles on this issue.

In the case of German chamomile, yes the azulene's and farnesene are
acknowledged anti inflammatory. However, there are very likely other
compounds that contribute to that effect, or contribute to a wider spectrum of
activity than simply antiinflammatory.

Just look at eucalyptus, most say "oh yes it's the 1.8-cineole that is
antibacterial". Yet, I have papers where the extracted cineol does nothing, and
a few researchers believe the antibacterial action of this oil has nothing to do
with the cineol but is other "unknown compounds".

Most people are familiar with synergistic activity, that is the way most botanical
extracts work, i.e. hundreds of chemicals working together to create an
extremely wide spectrum of therapeutic (or poisonous) actions. After all that's
what the living plant does, it has to perform a multiplicity of tasks to survive,
requiring many different chemicals for many different purposes.

So much for the attribution of aromatherapy therapeutic activity based on
major compounds, it really is childishly simplistic chemistry. It is promoted by
people who really do not have an adequate knowledge of the subjects that
they teach.

Hope this gives you all food for thought. Martin.

2) Herbal use versus essential oils
A few weeks ago someone questioned my statements that; "therapeutic
actions from a herbal preparation are frequently unjustified when the same
plants oil is used".

This is a highly complex issue and not something the vast majority of
aromatherapy writers have investigated properly. As most of you know by
now, I am adamant that many of the properties that the authors and teachers
give oils are not correct. This is because in the majority of cases they give
exactly the same therapeutic uses for the externally applied oil as the herbal
preparation given internally.

I will just give a couple of examples of traditional versus modern use.
JASMIN. The flowers have an ancient herbal use tradition as well as for their
beautiful perfume. Jasmin is one of those plants that has had huge of amounts
of research devoted to all aspects of its horticulture, production and chemistry.
The chemistry varies dramatically between the growing flowers, the picked
flowers and the absolute. For example, it has been found that flowers picked
at night contain over 4 times more indole than in daytime picked flowers.
Other chemicals only appear in the living or picked flowers and are absent from
the absolute or oil.

In herbal medicine in the past, and still in some societies, a vital part of the
training is education on when a herb is best picked to give the desired
therapeutic or poisonous result. This is why a good deal of astrology was
woven into herbal practice more in the past than now. Herbalists then were
more aware of the importance of time; the moon and stars cycles and weather
for when herbs should be gathered. Theophrastus recorded some of this
ancient knowledge in his books. The Ancients knew that effects observed in
practical use varied, although they did not know the chemistry.

So getting back to Jasmin. If the Indian herbalists picked the flowers at dawn,
at night, or in the day, then the conditions treated may well differ. When
these therapeutic treatments were recorded and then translated into English it
is quiet obvious that important information such as gathering time was often
omitted. We commonly find the same vital missing information in Chinese
medicine and Native American medicine.

So not only do we get the difference between the traditional use as herbal
infusions, etc. compared to the use of the essential oil/absolute externally, but
we also get these huge differences in chemistry depending on when the plant
is picked.

It is from herbal books that most aromatherapy authors get much of
their information.
A few (a very few) included information from the old
pharmacopoeias for the use of essential oils, but these uses were generally for
the internal consumption of the oils.

In some cases the general actions of herbs versus oils do correlate for a limited
number of conditions. For example a drop of peppermint oil will calm a minor
stomach upset as also will a cup of peppermint tea. However, the many other
actions of the peppermint tea such as an astringent action on the gut lining
which helps calm diarrhoea cannot be expected from the essential oil.
Therefore, when I see it suggested that rubbing a bit of peppermint oil on the
skin in massage will cure diarrhoea, it tends to make me feel sick!!

3) Date Aug. 1998

Reply to Lowana re herbs/oils
Yes, I do make generalisations because it would be impossible to go through
every incorrect statement made in every aromatherapy book. The number of
claims made of therapeutic properties for essential oils, which are wholly based
on the traditional use of the herb, is vast.

Lowana, you are certainly not someone I wish to have a go at, but I do find it
amazing that a University educated scientific worker like yourself, seems to
accept the statements made by these people who barely have the first clue
about the subjects they write and teach on.

Now as to specifics you mentioned. I am not giving references as they are to
be found in any serious study of the history of herbal medicine:

Clary sage - no traditional uses of the essential oil. The herbal infusion was
given to expel the afterbirth or dead child - see culpepper.

Cajuput - extensively used as herbal infusions in Vietnam and surrounding

Any of the citrus oils - not much as traditional medicines, mainly for food

Eucalyptus - yes, was used extensively as a herbal preparation and the
infusion is mentioned under the term 'kino' in several pharmacopoeias.

Frankincense - yes, the resin extensively used internally and externally - see
my book Frankincense and Myrrh by M. Watt and W. Sellar.

Lavender - was extensively used in many parts of Europe as a herbal infusion
for many problems and still is used by herbalists as an infusion.

Melissa - there is absolutely no traditional use of the essential oil. All the
aromatherapy information is based on the plants long history as a herbal
infusion. With maybe one exception, in that the oil is proven antibacterial.

Neroli or orange blossom - widely used in the Mediterranean area as an
infusion of the dried flowers for treating depressive type illnesses as well as the
distillation waters for skin conditions and other conditions.
Patchouli - not much known on its herbal use, but neither is there hardly any
accurate aromatherapy therapeutic use. An oil always primarily for the
perfume trade.

Pelargonium - no traditional uses of the oil. Native South Africans used
the herb as an emmenogue (meaning to start menstruation which can stop due
to malnutrition).

Pines – the herbs and resins have been used for thousands of years in various
kinds of preparations.

Rosewood - the heartwood was never used by the natives of South America.
All aromatherapy uses are 'invented' based on this oils chemistry which is
mostly wrong anyway.

Sandalwood (ground wood) was used in India as a paste applied to the head
to reduce a high temperature and decoctions of the wood were used to treat
urinary tract disorders.

Tea tree - the aboriginal peoples of Australia used it as an infusion as did the
later European settlers.

Ylang ylang - no traditional medicinal uses that I am aware of, but neither is
there any accurate aromatherapy therapeutic uses.

On the chamomiles you are correct to a degree. However, never forget that
new compounds are constantly being discovered in herbs and essential oils
which have been analysed over and over again. Therefore, attributing
therapeutic activity based on current knowledge of given compounds
can be most unreliable.
This is the major problem that the French
aromatherapy teachers seem to fail totally to comprehend. Anyway that was
not the issue we were talking about. My point was that most of the oils you
mentioned did not have any evidence whatsoever of having a physical
emmenogue action, while several have been used as herbal preparations for
that problem.

I am NOT saying these oils do not have therapeutic uses, but by and large
most are not well documented. What I am absolutely certain of though, is that
most of the claimed physical effects in aromatherapy are based on the past use
of the herb, which may or may not have similar actions to the oil. Certainly in
many cases the compounds occurring in the herb have a far wider spectrum of
therapeutic activity than those occurring in the same plants essential oil. A
classic example of this is peppermint oil, a powerful CNS stimulant, whereas
the herbal tea has a short lived CNS stimulating action, followed by a longer
lasting sedative effect caused by the water soluble compounds which do not
occur in the essential oil.
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