Our digestive system is the place we bring the outer world inside us, work on it to absorb what is useful, and eject the rest. It is where we make ourselves who we are, and where we relate most intimately to our environment. It really is our physical personality – our visceral being.
So it is not surprising that the digestive tract, the gut, is highly intelligent. The gut also produces more hormones and neurotransmitters than the rest of the body put together, is by far the major part of our immune system, with the liver it is the centre of our metabolism, processing and detoxification, and it dominates the body’s cleansing functions.
A healthy human gut is also very robust, able effortlessly to manage a vast diversity of substances. Earlier cultures saw it like a cooking oven or even furnace: in Ayurveda it is agni or digestive fire, and digestive processes are included in the Chinese san jiao ‘Three Heaters’. The western view emerged with the ancient Greeks: Plato had explained vital heat as a process of digestion. Nowadays we can describe digestion correctly as an enzymatically controlled combustion, just like fire generating heat and energy and leaving ash.
We are right to regard digestion with awe, to warm ourselves on its fire, and to see it as literally fundamental. The herbalist uses the digestive tract as a vehicle for healing, operating gut processes and receptors in much the same way as an acupuncturist stimulates points on the skin, both nudging reflex corrective responses. It is even likely that most herbal impact is in the gut. This is where we work!
This section is no replacement for the thorough study of digestion and its ailments. Instead we will pick out those highlights that best guide herbal approaches.
Our gut is intelligent
The gut is like an assembly line in reverse, rendering finished food products into fuel and structural materials, and ejecting waste. Even as a dis-assembly line it will only work efficiently if each stage is paced and coordinated with the next. There needs to be some very sophisticated information exchange back and forth along the tract. This is provided by gut wall receptors linked to layers of nerve plexuses throughout the gut wall, culminating in ganglia, ‘little brains’, scattered through the abdomen. Once food is swallowed its processing is done entirely by this ‘enteric nervous system’ without the need for the brain to get involved at all until it reaches the other end. Although the enteric system is connected to higher centres by the vagus nerve and the full panoply of sympathetic and parasympathetic nerve fibres these act as influencers rather than direct the action.
A simple example of this local control is the ‘Law of the Gut’, in which food is moved in one direction simply by the way the gut wall muscles are wired.
The presence of food and metabolites also induces pulsating patterns of secretions and gut wall activity. With such coordinated responsive performance the digestive system shows all the characteristics of a slef-organising complex living system. It will learn to accommodate to circumstances, to establish a new equilibrium even if the diet or environment changes.
Take home herbal message. In the vast majority of people the gut knows what to do! If it is misperforming then it may be better to help reboot it to its default program (in computing terms), so as to give it a chance to learn new patterns, than to force it to to behave. Taking antacids, H2 blockers like omeprazole, antispasmodics like buscopan and immodium or stimulating senna-like laxatives may be necessary for immediate relief but should be considered second-best approaches long term.
Our gut is emotional
If, has been said, emotions are what hormones feel like, then the gut generates more emotions than the rest of the body combined! There are known to be over a hundred hormonal-substances produced in the gastro-intestinal system, most of which have widespread activity around the body and into the brain.
As one would expect this vast hormonal array is mostly concerned with managing food intake and processing, messengers that affect appetite and satiety, hunger and the satisfaction associated with eating. A ‘comfort food’ truly is a hormonal-emotional event and ‘gut feeling’ is very real. For example the gut wall contains enterochromaffin cells, the most abundant endocrine cell in the body, generating 90% of all serotonin, the ‘happiness hormone’.
Opiate-like enkephalins are also generated from the stomach and duodenum, and gut hormones include one of the most powerful mood changers of all: insulin. This is released by the movement of sugars into the blood and intimately linked with fluctuating blood sugar levels, with consequent effects on stress, cognition and appetite control. It is designed to reduce appetite when sated, like another hormone leptin which operates when fat levels build up in the fluids. Another appetite regulator, found not only in the gut but throughout the body is cholecystokinin. This is one of the hormones implicated in the action of bitters for its effects on intestinal and gallbladder activity, digestive secretions, and on other hormones, including insulin. Other appetite managing hormones released after eating include oxyntomodulin (that also modulate stomach acid production), glucagon-like peptide-1 (GLP-1), pancreatic polypeptide (PP), and peptide tyrosine tyrosine (PYY). Glucagon-like peptide-2 (GLP-2) is also generated after eating but appears mainly to help maintain gut wall integrity. The list of hormonal-like substances also include somatostatin, growth hormone releasing factor, the insulin antagonist enteroglucagon, neuropeptide Y, vasoactive intestinal polypeptide (VIP), motilin and substance P.
Other familiar gut hormones are gastrin (increasing stomach acid, gut activity, and gut wall integrity, as well as various digestive secretions) and its antagonist secretin (producing alkaline bicarbonate in the duodenum and a major generator of insulin).
The best know appetite stimulant is ghrelin, though its performance is impaired by extremes of metabolic activity, levels rising ineffectively in anorexia and lowered in obesity. It has a significant impact on the brain’s response to food.
Note that most of this impact of the gut on mood and emotions goes much further than the ‘gut-brain axis’ which is often assumed to summarise the neural connections between the two regions. Rather the gut should be seen as intimately linked at every level to the brain and higher control functions.
Take home herbal message. The most pressing medical interest in gastrointestinal hormones is in the management of obesity and its related health problems. For the herbal practitioner being able to affect these humoral responses represent much wider opportunities to affect well-being from the gut surface. There is intriguing research that links serotonin-releasing chromaffin cells to volatile oils found in spices and culinary herbs.
Our gut is our immune system
The largest mass of lymphoid tissue in the body is closely associated with the gut wall: gut-associated lymphoid tissue (GALT). It is found in large accumulations like tonsils and appendix, in the Peyer’s patches that are found across the lower gut surfaces, as well as scattered more finely throughout the gut wall. GALT consists of immune cells such as B and T lymphocytes, macrophages, antigen-presenting cells, including dendritic cells, and specific epithelial and intra-epithelial lymphocytes.
This is not surprising. Most of the contact our immune system has with the outside world is in the gut. What is important to understand however is that immune defences are far wider than being able to produce the right sort of antibody or T-cell. There are three levels of immunity, illustrated here. The priority is to deal with threats with minimum complications; we can see them as rings of defences.
Barrier immunity starts with digestive secretions: notably stomach acid and gastric and intestinal enzymes, and bile, supported by normal peristaltic movement of the gut muscles. If these work well food is sterilised and most immunological content (antigens) is neutralised. It is only material that has escaped this assault that is presented to the deeper immune defences. Clearly to avoid increasing immunological complexity it is better to clean up food with robust upper digestive functions.
Innate immunity involves a massive array of scavenger or ‘phagocytic’ cells, in two main groups: 1) macrophages or activated lymphocytes, and their superpowered derivatives natural killer cells, and 2) polymorphonuclear leukocytes (neutrophils, eosinophils, and basophils and their close relatives histamine-producing mast cells). Their role is to clean up debris, provoke appropriate inflammatory responses, and to act as an immediate defence against threats to the body. To do this they also engage various chemical agencies, known as cytokines, that can induce inflammation and fever. When under particular duress, and usually in association with adaptive immune defences, they can generate an enzymatic cascade called complement that markedly amplifies their defence activities. In the gut these cells are concentrated as far up as the throat (eg in to tonsils) and down throughout the digestive tract, including the appendix. In the lower reaches intestinal macrophages are tempered by signals from mucosal cells to downregulate their defensive activities so that they can co-exist with the microbiome, and are therefore less prone to provoking inflammatory activity. The largest macophage population, known as Kupfer cells, are based in the liver to help clean up potential problems that have reached the portal circulation that drains the gut for ‘first pass’ processing by the liver.
The scavenger cells of our innate immunity do not need priming and are battle-ready. They also move fast and dominate the immune responses to one’s first exposure to a threat. Their responses, including in generating inflammation and fever are overt and open to direct therapeutic management, including by herbal and home approaches. Because A robust innate immune system is another protection against immune complications. However they also are closely integral with the next more sophisticated level of defence.
Adaptive immunity, involving antibody production by B-cell lymphocytes and adapted T-cell lymphocytes trained to target foreign proteins and cells respectively, is both much cleverer at identifying danger, and more dangerous itself. Cross-reactive responses (in which the immune system mistakes a healthy tissue for a pathogen) and autoimmunity (in which the attack is to one’s own tissues) become more likely the more acquired immunity is engaged.
To reduce this danger much of this activity is kept at the gut surface: IgA antibodies are produced here in quantities greater than all other types of antibody combined. Their production is primed by exposure of other GALT cells but their role is primarily to keep antigens away from the gut wall and deeper tissues. Other key types of cell in adaptive gut immunity are dendritic cells (link innate and adaptive immunity by presenting antigens in a managed way to antibody-producing cells), M-cells clustered around apparent breaches in the gut wall known as Peyer’s patches, these also made up also of congregations of lymphocytes, macrophages, T-cells and other GALT tissues. Together these Peyer’s cells seem to invite potentially dangerous antigens into an immunological spider’s web so that defences can better be primed to them.
Take home herbal message. There is no doubt that a major strength of herbal medicine is in optimising key digestive functions and maintaining gut wall integrity so as to reduce immunological complications. Herbalists have a useful toolkit in the management of food intolerances and allergies. There are also unique approaches to wider immunological complications: those associated with inflammatory bowel disease (eg with immunological cross-reactivity to bowel flora), and in almost any case of autoimmunity.
Any bitter or aromatic digestive remedy can be seen as supporting barrier immunity, as can any herb that maintains gut wall integrity by reducing inflammatory or other damage. Hepatic and choleretic herbs can influence the properties of bile, one of the most important determinants of gut wall and microbiome health. Although based mostly on clinical experience there are reasons to believe that many herbal ingredients: eg. resins, hot spices, bitters, some volatile oils, and the tingling alkylamides of echinacea can productively stimulate innate responses and potentially spare further immunological trouble.
We can eat anything!
… well lots of things anyway! Humans biologically are classified as omnivores. Our digestive system more closely resembles that of other omnivores like the rat or pig, rather than herbivores or carnivores. In other words we have evolved to eat a very wide variety of foods indeed. Humans are quite healthy eating largely vegetarian diets (as in Asia), largely animal diets (as in parts of Africa) and almost entirely seafood diets (as in the Inuit near the North Pole). In evolutionary terms this is the physiological correlate of having a large brain: we are a supremely adaptable species able to colonise every corner of the globe.
Our liver is also the home to a defence system as adaptable and complex as the immune system itself: the cytochrome P450 (CYP450) enzyme family. This array can identify almost any foreign biological molecule (xenobiotic), tag it and enable it to be processed. These two stages of ‘hepatic biotransformation’ are referred to as Phase I and Phase II detoxification. In Phase I, CYP-450 and other enzymes induce oxidation, reduction or hydrolysis to generate a reactive site on the target molecule; in Phase II the reactive molecule is quickly conjugated with glucuronate, sulfate, glutathione, glycine or other amino acids to make the molecule more polarised ( electrically charged) and thus more able to be excreted from the body. Although Phase I processes are risky (the reactive molecules they generate require strong accompanying antioxidant processes and they become more dangerous with poor diets and industrial pollution) a robust Phase II (helped by vegetables and fruit) can usually protect the body from harm and can ensure that the liver can cope with most material in the natural environment that we might ingest.
Our bodies evolved to deal with natural challenges and we should aim to eat food that is as close to nature as we can: there are real benefits for all the functions above from eating organic food for example. There are clearly modern challenges to healthy detox functions, notably the proliferation of man-made chemicals in the environment, and there have long been risks associated with heavy metal contamination of food. However it is reassuring that more people are living to a grand and healthy old age in spite of these threats. Our digestive system and a liver show extraordinary capacity to cope and this can be celebrated.
In the past people ate when they were hungry, they had ‘hearty appetites’, gave thanks for what they were able to put on the table and relished their food all the more because they were not able to pop out and pick it up from their local supermarket. The old English expression ‘belly-cheer’ well summarises the sheer pleasure of eating well when one could. Such reflections are an antidote to many modern food problems: they remind us that a healthy digestion is a robust one. Clearly it makes sense to eat as nature intended as far as possible, to avoid excesses of fast carbohydrates and other junk food (not too much ‘comfort food’ perhaps!), but mainly to eat with joy!
Take home herbal message. Helping the digestion become more robust is where herbal treatment can differ from nutritional approaches that focus on excluding potentially upsetting foods. There are certainly many herbal remedies that support good digestive performance. We will have a look at some of these later in this section.
The digestive tract is home to a vast and diverse community of microorganisms, with up to 1000 distinct bacterial species, viruses, fungi and other micro-organisms that in total number many more cells than found in the human body itself. Altogether the microbiota also contain hundreds of times as much genetic material, giving them enormous capacity to affect our internal environment.
The gut microbiome is a significant part of our digestion. Among its many known roles it is involved in vitamin synthesis, helps with absorption of fats, and converts otherwise undigestible items into useful nutrients (for example gut bacteria convert important but unavailable plant polyphenols into assimilable and active simple phenols). It provides vast quantities of short-chain fatty acids (butyrate, propionate and acetate) that are major sources of energy for the gut and wider body. It acts as a further protection against inappropriate immunological reactions to food and helps to maintain a healthy gut wall. There is even evidence that a healthy microbiome literally makes you feel better by engaging with the gut-brain axis and the production of serotonin from enterochromaffin cells.
On the other hand people with irritable bowel syndrome, obesity, and a range of immunological and inflammatory diseases, including neurological problems like Alzheimer’s disease, Parkinson’s and depression have been shown to have alterations and depletions in gut bacteria.
A key insight into the microbiome is that it is in an intimate relationship with us, its ‘host’. There are constant interactions between the two parties. The gut wall produces a range of materials that sustain healthy populations and in return play a key part in maintaining gut wall integrity and defending against harmful organisms. There is a close relationship between the microbiome and the bile from the liver. Bile has a major impact on the microbial populations and interacts with them to provide the main laxative effect in the bowel and some of the more significant impacts (positive and negative) on gut wall integrity.
The microbiome is clearly an ecosystem, even a cosmos in itself. Like any other self-organising living system it combines remarkable stability with constant flux. The cells nearest the gut wall tend to be the most stable, whereas those in the central lumen change with each meal.
Profound therapeutic conclusions can be drawn by understanding this. There are essentially two ways to improve the balance of the microbiome: probiotics and prebiotics. With probiotics the aim is to repopulate the microbiome with healthy cultures eg Lactobacilli and Bifidobacteria (faecal transplants are more direct versions of this approach). Although there is some evidence that oral probiotics can be a healthy tactic there are two drawbacks: 1) the job of the stomach is to sterilise food so probiotics do better when there is a fault in stomach function; 2) a self-organising biome that regenerates itself several times an hour may not be too affected by new arrivals from above.
A more productive approach may be to consider the gut microbiome rather like the organic farmer considers the soil: as a rich nurturing biome that needs feeding in turn. Prebiotics are substances that support healthy microbiota. They can be seen as the equivalent of the farmer’s compost: creating the best environment for this rich soil within us.
Prebiotics usually refer to complex carbohydrates, provided for example in root vegetables, pulses, grains and the onion family, that survive digestion and provide nourishment for beneficial bacteria. However it is now known that both polyphenols and spice constituents are prebiotic and this property is likely to be extended to other plant constituents. Importantly these latter candidates appear support healthy microbiota by affecting their dialogue with their host.
Take home herbal message. We can see the gut microbiome as we do the rest of the digestion, as a self-organising living system that is better supported than manipulated. It is likely that some of the most effective herbal measures we have are to improve other upper digestive functions (including liver and bile), so that what reaches the microbiota is as healthy for them as possible. Adding spices and polyphenol-rich herbs to the mix is a bonus.
As main field of herbal operations: acupharmacology?
If one sorts herbal remedies by their key active phytochemical groups something very interesting emerges. It really does look like much herbal activity is confined to the upper reaches of the gut!
Many plant constituents are not easily assimilable or are quickly neutered in the stomach and duodenum. Most are provided at doses that will not have much impact after travelling 7-8 metres through the digestive tract. (Consider for example the effect of a teaspoonful of herbs in a stomach producing up to 1.5 litres of juices per day.) On the other hand many have direct effects on gut wall receptors from the very first stages of entry. As we learn more about the connections between gut and the rest of ourselves we can see that these trigger points can account for a wide range of effects through the rest of the body.
We can see the herbal field of operations as the gut wall surface, inducing reflex healing responses through the rest of the body, in a way analogous to stimulating acupoints on the skin: ‘acupharmacology’ instead of acupuncture.
Let’s look at some examples. These archetypal plant constituent groups also form the basis of core sensory qualities in the descriptions of the herbs in Herbal Reality. They provide a direct experiential means of understanding the power of herbs. That their effect is so immediate, within minutes of swallowing, adds to the intimacy we may have with our remedies.
Mucilages. These are complex carbohydrate based plant constituents with a slimy or ‘unctuous’ feel especially when chewed or macerated in water. Their effect is simply a physical coating of exposed surfaces. Throughout history and prehistory they were favourite wound remedies, for their soothing and sometimes healing effects on damaged tissues. Now they are used more for these effects on the upper digestive lining, from the throat to the stomach, where they can relieve irritation and inflammation such as pharyngitis and gastritis. Some of the prominent mucilaginous remedies like slippery elm, aloe vera and the seaweeds can be used as physical buffers to reduce the harm and pain caused by reflux of excess stomach acid. Much mucilaginous activity is lost within a few hours in the stomach but some seed mucilages, such as in psyllium seed, flaxseed (linseed) or guar bean survive digestion to provide bulking laxative effects in the bowel. These can also reduce rate of absorption of sugar and cholesterol.
Mucilages are also widely used to reduce dry coughing. Here the effect seems to be by reflex through embryonic nerve connections: soothing signals from the upper digestive wall are translated into reduced activity of airway muscles and increased activity of airway mucus cells.
Tannins. The puckering taste you get with many plants (the most familiar is black tea after being stewed too long or some red wines) is produced by tannins. These are used in concentrated form (eg from oak bark) to make leather out of animal skins. The process of ‘tanning’ involves the coagulation of relatively fluid proteins in living tissues into tight clotted fibres (similar to the process of boiling an egg).
Tannins in effect turn exposed surfaces on the body into leather! In the case of the lining of mouth and upper digestive tract this is only temporary as new mucosa are replenished, but in the meantime inflamed or irritated surfaces are calmed. Tannin-rich plants are immediate treatments for gastrointestinal infections, including when these lead to diarrhoea. The leather effect numbs sensory nerve endings and reduces the stimulus to extra peristaltic activity.
In the case of open wounds tannins can be a life-saver – when strong (as in the bark of broadleaved trees) they can seal a damaged surface. Many tannins, the reddish-brown ‘condensed tannins’, are also polyphenols and can reduce inflammation and oxidative damage.
Bitters. The archetypal ‘acupharmacology’ treatment, bitter-tasting molecules work instantly and directly on bitter receptors in the mouth and gut (and now also found throughout the body) to cause immediate changes in many digestive and metabolic functions. They were some of the most valuable remedies in ancient medicine, sometimes described as ‘bitter digestives’.
Bitter receptors send signals via the gustatory nerveto release hormones like cholecystokinin and gastrin. Such effects increase appetite, digestive secretions, stimulate bile flow, balance blood sugar levels. They are classic treatments for loss of appetite, poor digestion, ‘biliousness’ and illnesses like hepatitis, diabetes, fever of gastrointestinal origins and wider liver-related toxicities.
Hot spices. These have been some of the most valuable commodities in human history, favoured for their warming properties as well as for instant benefits on digestion, and forming the basis of the great international trade routes into the Europe from antiquity. They have been classified as ‘warming digestives’ or with equivalent descriptions for all that time.
In spite of this huge popular experience science has been slow to catch up. However there is evidence that ginger and probably cayenne increase absorption of foods and medicines. Ginger has also been shown to have antinausea and antiemetic activity in humans. The likelihood that this is due to a direct effect on the stomach wall is reinforced by evidence that it protects against gastric irritation by alcohol and non-steroidal anti-inflammatory drugs (NSAIDs) as well as other stressors. Cayenne contains capsaicin which has been shown to increase intestinal motility. including by interaction with transmitter agents substance P and vasoactive peptide, and to reduce absorption of glucose, cholesterol and fats.
An important example of this spice group is ginger’s relative turmeric. Its most prominent active principle curcumin has the same vanillyl group as zingerone (from ginger), piperine (from pepper) and capsaicin. It is moreover very poorly absorbed and most of the benefits of turmeric are likely to be from its effects within the gut (see the turmeric monograph for more).
Volatile oils. These fragrant plant principles have been termed ‘aromatic digestives. Many, favoured in the use of spices like cinnamon, cardamon, and fennel are like the hot spices also ‘warming digestives’. Others like those of the mints, chamomile and lemon balm might be considered more like ‘cooling digestives’. All are also ‘carminatives’, remedies used to reduce colic and irritability in the bowel.
Resins. These are most familiar as tacky discharges from pine trees (and as the substance in amber, and rosin for violin bows). They are complex mixtures of phytochemicals with immediate stimulating and astringent properties on mucosal membranes of the mouth, throat gullet and stomach. They do not survive to reach any other part of the gut or body. Resins were the original antiseptic remedies, ground and applied as powders or pastes to wounds or inflamed tissues, and were also used for mummification. With alcohol distillation it was found that they could be dissolved in 90% alcohol and in this form they remain a most powerful mouthwash and gargle, for infected sore throats and gum disease (best combined with concentrated licorice extracts to keep the resins in suspension and add soothing properties). It appears that they work both as local antiseptics and by stimulating white blood cell activity under the mucosal surface. Biblical remedies like frankincense (Boswellia) and myrrh can be augmented by high alcoholic extracts of calendula in modern practice.
Saponins. These are natural detergents found in many plants. They sometimes have a sweet taste, are steroidal in structure, and are the basis of key adaptogenic or tonic remedies like ginseng, licorice, ashwagandha and many others listed as convalescent remedies in the Fatigue section.
The detergent properties of these common plant constituents are likely also to have significant properties on gut function. One effect for some plants like squill or cowslip appears to be gentle gastric irritation leading to a reflex stimulating expectoration, applicable to congested bronchial problem (a reverse effect to that of mucilages).
On the other hand, particularly in the lower regions of the gut the detergent effect is likely to improve some aspects of intestinal permeability. There is evidence of improved protein absorption and reduced cholesterol uptake (eg in the saponins of fenugreek and alfalfa); interactions with bile salts have been postulated for some of these effects. There are saponins in spinach, beet, asparagus which have been considered to provide an enhancing effect on assimilation.
Anthraquinone laxatives. Plants like rhubarb, senna, cascara, frangula and aloes have been well understood for their effects on the gut from prehistory: their laxative impact 8 hours or so after ingestion is obvious! These effects are also largely confined to the gut: systemic absorption is limited, and generation of irritant laxative principle is mediated in part by the microbiome.
Bulk laxatives. Plant materials are by far the main source of ﬁbre: undigested food residue to bulk up the stool contents. Not only does fibre maintain normal bowel movement (both to reduce constipation and irritable bowel syndrome IBS), it acts as prebiotic to maintain a healthy microbiome, it relieves inflammatory bowel diseases, counteracts potential irritative effects of bile metabolites, and slow the absorption of sugars and cholesterol.
Immuno-stimulating polysaccharides. These have been identified as key principles in remedies as disparate as echinacea and the mushrooms. That they cannot survive digestion (they are quickly converted into simple sugars in the stomach) means that any effect must be on the surface of the upper reaches of the gut. Among candidates for this are cells of the innate immune system (eg in the tonsils) and the IgA-producing immune cells (possibly also those producing IgD and IgE antibodies) which line the gut even at these levels (see above). These latter behave as signalling and alerting mechanisms for wider immunological and inflammatory responses around the body.
Managing digestive problems
From what we have seen so far about both the qualities of a healthy digestion and of herbal remedies it becomes easier to set up herbal approaches to challenges that arise.
The following is brief review of a few functional digestive difficulties, and does not cover more serious diseases. Each situation will be different and it is usually better to go beyond the symptoms to understand the background factors that help to create them. However we can summarise the start-up approaches in the following sections. Throughout refer to the previous section for guidance to each herb category.
Literally meaning loss of appetite, anorexia is most often a symptom of many illnesses, from respiratory infections to cancer. Improving appetite is therefore often a central task in convalescence, the recovery phase. Depending on the constitution and presentation one can choose from either warming aromatic, or cooling bitter digestives. It usually is wise to avoid very strong spices and start with teas and other gentle doses.
Anorexia nervosa is a particular and complex cause, where loss of appetite is tied up with much wider difficulties. Using any herbal remedies may need careful negotiation. However warm spicy teas are probably as good as any place to start.
2. Functional dyspepsia and reflux (GORD)
Most stomach problems are referred to as ‘functional’: in other words they are problems of performance rather than observable diseases. This makes them very amenable to herbal remedies which can help in retraining the system to perform better. However they may lead on to more serious conditions if left unresolved.
One job of the healthy stomach is to produce hydrochloric acid at sufficient strength to sterilise food and begin to break it down. It is a biological miracle that this does not usually lead to damage of the stomach wall. The key is the massive and constant flow of mucus from other glands that propels the acid (only formed after it has left the cells that produce it) away from the wall. This acid is important: about 10% of people do not produce enough (they are ‘hypochloridic’) and are prone to gut infections and food poisoning. The same risk follows if excessive antacid medicines are consumed to treat too much stomach acid.
Excess acid production can be caused by stress, poor diet, reactions to specific goods, smoking and alcohol, effects of medication (eg aspirin and NSAIDs), or infection with Helicobacter pylori. It can lead to serious conditions like gastritis, ulcers (in stomach or duodenum) or cancer. Often its cause is elusive and may follow disruption of wider control systems in the gut (including GI hormones). Research has confirmed a common clinical observation that functional dyspepsia is often accompanied by other health problems. It is almost always better not to treat these problems on their own and a holistic approach to such symptoms is wise. Using alkalis like milk of magnesia, PPI medicines like omeprazole, or histamine blockers like cimetidine relieve symptom at best but may further disrupt control symptoms at worst. Herbal symptom relief that is less suppressive includes the use of mucilages like slippery elm powder that simply and safely augment natural mucus protection. Stomach calming herbs like chamomile, lemon balm, meadowsweet and peppermint (as a tea, not oil) may provide instant relief without further complications.
Gastro-oesophageal reflux disease (GORD – or GERD if using American spelling) results from the movement up into the gullet of stomach acid – through a defect in the sphincter between stomach and gullet – hiatus hernia. The symptoms start with heartburn and progress to reflux of sour fluids into the mouth, and then possible cough and hoarseness. Weight gain, excessive abdominal exertions and stress can all exacerbate this condition. However it it well worth remembering that the sphincter here is formed by the diaphragm: combining a holistic herbal approach to functional dyspepsia with a long-term programme of breathing exercises is one of the most productive solutions.
Irritable bowel syndrome is a diagnosis that is both much used and rather useless. Doctors use it to cover any lower digestive problem that cannot be identified by scan or other investigation. Patients use it because it gives a medically-unexplained problem a name. Others refer to it as a negative diagnosis – saying what something isn’t rather than what it is. A constructive interpretation is that IBS is another example of poor digestive performance, in other words ready for re-training.
The many symptoms lumped under IBS (including variable bowel movements, bloating and colic) can have a wide range of causes. They may arise from food intolerances (see below), hormone fluctuations (eg in the menstrual cycle or menopause), as responses to stress or anxiety patterns, or as a result of ‘the wrong sort’ of bile (which may also have hormonal links). Working out which of these is involved will determine which approaches to use. One option is likely to include a careful programme of food eliminations and challenges
Herbal options for symptomatic relief will include warming or cooling bitter digestives (as appropriate), other carminative herbs (including strong peppermint preparations), bulking mucilaginous seeds, choleretic herbs like artichoke or dandelion root. Specific remedies from the above list include hops, linseed and wild yam.
4. Food intolerances (and allergies)
The discussion elsewhere in this section points to a herbal approach that at all times seeks to optimise healthy functions. In this light any sensitivity to food is a dip in robust digestion. The herbal instinct is to help bring our inner omnivore back, to ignite our digestive fire.
A food intolerance is any sensitivity to a food, such that eating it is associated with uncomfortable symptoms. These may be bloating, dyspepsia, bowel irritability or abdominal discomfort, or may stretch more widely to spark off joint pains, skin reactions, headaches or anything else. Causes may include poor upper digestive breakdown of the food, diminished digestive enzymes, or most commonly dysbiosis (upset gut microbiota). All of these will benefit from digestion-enhancing herbal measures as outlined earlier.
Food allergies are a less common and very specific form of intolerance in which a food constituent (most often a protein) becomes an immunological challenge. It is astonishing that this does not happen more often and is a testament to the formidable barrier and innate defences referred to earlier, that spare the adaptive immune system from dangerous engagement with food. The most common examples of food allergies are to beta-lactoglobulin in cow’s milk (most often as this is often introduced before the baby’s immune system has properly matured) and alpha-gliadin, a fraction of gluten in wheat, spelt, rye and barley, known as coeliac disease. With the exception of the latter, food allergies are often ‘masked’, so well covered up by the body’s stimulating stress hormones that a sufferer gets temporary benefit from eating the allergen (and so it is often one of the most common foods on the menu).
In all cases of suspected food intolerance the surest way to check is a rigorous elimination programme. The suspect food should be removed entirely from the diet (including all foods that contain it in even minute quantities; in the case of dairy that includes any yoghurt, butter, cream or any products that contain them) for between 10-14 days. A diary should be kept: in the case of a masked food allergy there can be a day or so of ‘cold turkey’ symptoms as the hormonal cover-up is not engaged. Note any changes at all. Then reintroduce the suspect food for a week or so and note any further changes. Then repeat the elimination and challenge to be sure – it may be that changes noted in the first round were due to other factors.
If a food is found reliably to be upsetting then the first step is to keep off the menu for some time longer. However as we have noted this ideally should be a temporary measure. There is a herbal opportunity to enhance upper digestive functions so that food is better neutralised, and in the case of food allergy, proteins and other large molecules are made immunologically safe by being properly broken down. Once more we aim to bring the digestive system back to its hearty robust normality.