Native Healers. Anita Ralph
anti-inflammatory constituent of willow bark working in synergy with other compounds. It is now recognised that the anti-inflammatory effects of willow are not entirely the result of salicylates.10
Fibre is another obvious dietary compound that is a potential contributor to health such as the soluble fibre found in linseed, or flax (Linum usitatissimum L.). Soluble fibre has an important prebiotic role as well as contributing to hormone balance and regulation.
Herbal medicine recognises that plant foods can have beneficial well-being outcomes, and many ‘kitchen herbs’ are positively medicinal. For example we can take therapeutic quantities (antibacterial quantities) of raw or powdered garlic (Allium sativum L.).
The herbalist may make recommendations about diet to utilise the helpful benefits of certain foods, but is also focussed on the therapeutic application of plant medicines to restore resilience and function. An assessment of the person's constitution and condition may also result in recommendations of eating certain foods. This is more than just about phytochemicals, in that it is also an ‘energetic’ assessment.11
Choosing a plant for an individual may involve interpretation of numerous beneficial compounds, so that a just a few herbs can formulate a prescription, yet have multiple therapeutic benefits.
The drug (herbal medicine) changes the physis of the body, while on the other hand the food increases its substance.
—Manfred Ullman12
Case history
A woman in her late 60s presented with a long history of digestive discomfort. She had persistent abdominal pain and bloating, with episodes or ‘flare-ups’ of frequent bowel motions—up to 20 per day. Between ‘flare-ups’ her bowel movements were twice daily but felt incomplete, and she had observed a corresponding urinary irritation if her bowels were very upset.
Diagnosed with coeliac disease, she also suspected she was lactose intolerant, and she successfully avoided those foods, whilst eating a balanced diet. She found that eating this way and taking probiotics had helped slightly.
She was motivated to see a medical herbalist after a prolonged ‘flare-up’ of her symptoms following a recent viral infection.
Using plants as a deliberate medicine to restore digestive function was discussed, and a herbal combination was suggested alongside the probiotic capsules and dietary care she had already introduced herself.
Her medicine contained agrimony herb (Agrimonia eupatoria L.), German chamomile flowers (Chamomilla recutita L.), lemon balm herb (Melissa officinalis L.), lavender herb (Lavandula officinalis L.) and Black walnut hull (Juglans nigra L.).
These plants were chosen for a variety of potential effects including antispasmodic, anti-inflammatory, increasing digestive enzymes, prebiotic, antiviral and relaxing and healing (vulnerary). The herbs used are gently warming (often useful for older people), and a balance between drying and moistening was also important.
The patient took a small dose of the combined herbal tincture at each meal to try to improve digestive capacity. She reported that within 24 hours she felt less bloated and thought some of the pains had subsided.
Within a week her bowel movements had regulated to two or three per day but were much more comfortable. After 12 weeks she had had no flare-ups, which had occurred at least monthly prior to starting treatment.
Changing her diet and taking probiotics had helped this lady, but the herbal medicines were specifically selected to address insufficiencies in the function of the gut and gently stimulate them to work.
Although identifying and testing secondary plant metabolites and compounds is a major focus of research, it is important that we should resist any temptation to assume that the action of any plant relies solely on the action of any single chemical or compound. The action of the whole plant is always more than the action of its parts. Synergy is increasingly seen as being a fundamental component of plant medicines in the biological sciences.6
Just as the human body can be broken down into parts in order to study its complexity, medicinal plants can be examined through their compounds, but the plant then needs to be reassembled whole for us to have completeness of understanding.
It is useful to look at plant compounds and constituents nevertheless as they can help to provide:
•Possible explanations for traditional use.
•Possible mechanisms for the medicinal actions of forgotten/un-investigated plants.
•Clarity about possible benefits or negative effects of medicinal plants.
•Illustrate the scope and diversity of plant pharmacology.
Secondary metabolites within a plant form part of an array of constituents, and here we look at four archetypal ones:
•Mucilages
•Tannins
•Saponins
•Essential oils
Mucilages
Mucilages are normal products of metabolism formed within plant cells, and may act as storage material, especially for germinating seeds where they act as a water reservoir.
Mucilages can be found in quantity in the epidermal cells of leaves, as well as inside seeds including psyllium, Plantago ovata Phil. (formerly known as Plantago psyllium and isphagula) and linseed, Linum usitatissimum L. Mucilages are also found in the roots of marshmallow, Althaea officinalis L. and in tree bark, for example slippery elm, Ulmus fulva Michx.13
Though extremely common in plants, gums and mucilages seem to be rather disregarded by pharmacologists. Their action in the human body is largely physical rather than chemical, and they are often capable of reaching the large intestine because they are not completely broken down by the stomach and small intestine in the digestive system. So they can have their demulcent healing effects all of their slippery way down the tubing.
Many well-known herbal medicines that are mucilage-containing have predictable effects on the digestive, respiratory and urinary systems, despite the fact that there will have been no direct contact with the mucilaginous compound beyond the digestive system; that is they do not come into physical contact with the lung or the bladder. This phenomenon raises an important pharmacological question often discussed in plant medicine—how do some medicinal plants manage to affect parts of the body, on a mechanical level, that they physically cannot reach?
It has been acknowledged that some body tissues—such as those found in the respiratory, urinary and digestive systems, share a common embryological root. Even after the embryo has developed and tissues have diversified, they may remain responsive to the same stimuli, and also respond similarly via reflex nerve pathways.11
Actions
Here are some of the potential medicinal actions of mucilages in humans:
•Demulcent (soothing, cooling, anti-inflammatory)
•Emollient (moistening, especially to mucous membranes)
•Nutritive (nourishing, improving tissue integrity)
•Emulsifying (making nutrients available for digestion)
•Prebiotic (encouraging microbiome establishment and diversity)
•Vulnerary (accelerating regeneration of tissues—healing)
•Aiding pharmaco-kinesis (helping with the movement of medicinal constituents into the body).
Traditional Western herbal medicine classifies mucilages as neutral in temperature and moistening. They are considered to be mild and agreeable, even to the most delicate patient. This traditional classification is recognised in addition to more recently discovered pharmacological properties. In Western herbal medicine, there is often