Dr Charles Forsyth

Ecological Physician




The Study of the Relationship between Organisms and their Environment

Ecological Medicine and Clinical Ecology are terms used to describe the practice of medicine where diagnosis and treatment are aimed at understanding and addressing the disturbed relationship between the patient and his/her environment.



The Failure of the Organism to Adapt to it’s Environment

Adaptability & Resilience

One of the most amazing aspects of living organisms is their resilience - their ability to not only tolerate but adapt to and even take advantage of changes in their environment.  In fact disease is the consequence of failing to adapt to the environment we are in - the less able we are to adapt successfully the sicker we become and sooner or later die. One very important measure of health is how adaptable we are - how well we cope with change.  Our health and survival is determined by the dynamic balance between our inner resources and integrity and the type, number and degree of external challenges.  If we are challenged too much, our chances of adapting successfully decrease, but on the other hand, if we are challenged too little our systems become lazy and loose their ability to adapt and thrive.

Boundaries - Our Interface with our Environment

The integrity of the interface with our environment is vital.  On a physical level this comprises our skin and mucus membranes - they form a barrier between us and the world outside.  They have to keep inside what should be inside and keep out what should be outside - and let in (actively or passively) what we require (nutrients, water, oxygen, light) and let out what we need to get rid of (waste products, toxins).  If the functional efficiency of these barriers is reduced, the consequences are very far reaching.  The defence systems have to be able to recognise accurately and reliably what is considered by the system as a whole to be okay, non-toxic, non-pathogenic, friendly from what is potentially not okay, toxic, pathogenic or enemy.  If it is too tolerant to it’s environment, toxins and organisms invade and have their play, while if it is too intolerant, hypersensitivity in one form or another results.  These basic principles can naturally be extrapolated to the psychological level, family units, societies/communities and the Earth’s ecosystem.

Environmental Change and Genetics

We live in an age where there have been such huge multiple environmental changes that have never remotely been seen before - and they continue at a greater and greater pace.  From a health point of view, for those of us in the developed world, some of the main changes have been to our Diet, Toxin Exposure and Psychological pressures.  And that’s not to mention many of the other huge global challenges, such as Environmental Pollution, Global Warming and Climate Change, Overpopulation, Natural Resource Depletion, Waste Disposal, Degrading Ecosystems / Loss of Biodiversity / Species Extinction, Soil Degradation, Deforestation, Ocean Acidification and Acid Rain, Ozone Layer Depletion, Water Scarcity and Pollution, Land Management and Urban Sprawl, Genetic Engineering, etc.

Our genetics have evolved slowly over eons and there is huge variation in the human genome (we are all totally unique, but much less so for identical twins) - and many variations are common to certain populations and may represent favourable adaptations to the environment the population evolved in - but they may be considerably less favourable in other environments.  A good example is skin pigmentation, where a high level is very protective when sun exposure is very high but results in poor vitamin D production in countries which have low levels of sunlight exposure, such as the UK.  Inherited genetic variations (polymorphisms) can have a major influence on our susceptibility to environmental factors such as pathogens, foodstuffs, chemicals, drugs, vaccines, etc., to many diseases and also our nutritional requirements.  Additionally we are finding that another more sinister gene/ environment interaction is remarkably common - and that is the formation of DNA adducts - which is the term for compounds binding to DNA which can then seriously modify gene expression.  It is my view these psychological and physical factors explain the fundamental causes of majority of our health problems.

Western Diseases

The spectrum of disease afflicting us in the developed world has changed radically from that of just a few generations ago and that experienced in less developed countries. Cancer and atherosclerotic disease (eg. ischaemic heart and cerebrovascular disease) now account for over half of all deaths (all ages) in the UK, while previously they were rare, as they are in most less developed countries.  Similarly allergic disease (asthma, hay fever/allergic rhinitis, eczema, urticaria (hives), anaphylaxis) are now also alarmingly and increasingly common, having been almost non-existent previously. Hay fever doesn’t even appear to have existed prior to the early 1800’s.  Whereas infectious disease which caused the majority of ill health and death has declined mainly as a result of improved sanitation and similar public health measures, we are now confronted with chronic diseases, the causes of which are starting to become a bit clearer.  Environmental factors appear to play a very major role - and this is certainly the experience of those of us working in ecological medicine.  People emigrating to the developed world rapidly assume pretty much the same disease pattern as those who have lived here all their lives - which means that inherited genetic factors can only play relatively minor role. If we look at human cancers as a whole, inherited genetic factors are thought to have a causative role in less than 20%, leaving environmental factors causing more than 80% - which includes smoking, obesity, infections, diet & nutrition, chemicals and radiation.  Then there is the enormous epidemic of obesity, Type II diabetes and metabolic syndrome.  In England, 24.8% of adults are obese and 61.7% are either overweight or obese - today's obesity levels are more than three times what they were in 1980, when only 6% of men and 8% of women were obese.

Treat the Cause

It is a fundamental principle of any system of medicine that the ideal of therapy is always to address the causes of disease where ever possible.  If the causes are primarily environmental or/and changes in our susceptibility to environmental factors, then it is logical that it is these that should be targeted.  And yet how are we treating the vast majority of disease at present? - with drugs.  Drugs don’t correct the primary causes of disease - disease doesn’t arise as a result of drug deficiency.  Even in infectious disease, the aim should be to strengthen the defence mechanisms and address why they are weak.  I am certainly not against drug treatment per se, I just believe we should have a flexible hierarchical approach and use therapeutic measures that are aimed at restoring optimal function and address causes first - and reserve drugs for when these measures alone are failing.  Drugs have a few downsides, as well as not treating causes, most are expensive and are inherently toxic (see the adverse reactions and precautions lists) - iatrogenic disease is extremely common.

Causes of Disease

So what are the causes of disease?  Here is my simplistic overview.  I find it useful when assessing and treating my patients.  All diseases, without exception, are caused by either internal or external factors - or more usually, a combination of the two.  It comes back to ‘nature’ and ‘nurture’. 

Internal Causes

  1. Inherited: genetic/chromosomal (including epigenetic), and homeopaths add ‘miasmatic’, etc - what we come in to this world with - our unique individuality with all it’s strengths and weaknesses.

  2. Acquired: what then develops, whether in utero, during or after birth, - as a result of environmental factors acting on inherited susceptibilities.

  3. Physical: anatomical, physiological, biochemical.

  4. Psychological: mental, emotional, spiritual.

  5. Psychoneuroimmunoendocrinology is the term that describes the main relationship/interface or lines of communication between mind and body - the nervous system, immune system and hormonal system.  Our mental and emotional state ultimately influences and controls all physical functions, whether consciously or subconsciously.

Interface/Membrane/Boundary Causes - all result from the interaction between us and the outside world:

  1. Taking in too much of what is bad for us – toxins/ organisms.

  2. Taking in too little of what we need – nutrients, incl. oxygen, light, water.

  3. Losing too much of what we need – nutrient and fluid loss.

  4. Losing too little of (ie. not excreting) what is bad for us – toxins, both endogenous and exogenous.

  5. Reacting too much - allergy/sensitivity/intolerance.

  6. Reacting too little - impaired defence/ immunity.

Environmental Causes

  1. Psychological Stress - external psychological demands and traumas.  Our ability to cope with psychological stress is determined by not only our psychological make up, but our physical health - so all of the above physical factors can have a huge negative effect.

  2. Nutritional / Dietary:

  3. Insufficiency: vitamins, minerals, fats, proteins, water, oxygen, etc.

  4. Excess - sugars, starches, specific fats, trans fats, salt, wheat, milk products, processed foods, food additives, etc.

  5. Microbial:

  6. Microbiome: imbalance, reduced diversity, etc.

  7. Pathogenic: bacterial, viral, fungal, parasitic, etc. - infection/overgrowth.

  8. Chemical Toxins: tobacco, alcohol, pesticides, pharmaceuticals, plasticisers, mercury, cadmium, arsenic, lead, aluminium, asbestos, benzene, toluene, xylene, chloroform, formaldehyde, PCBs, PBBs, PFCs, fluorides, bromides, etc.

  9. Electromagnetic:

  10. Toxic: ultraviolet light (UVA, UVC, UVB), microwaves, x-rays, gamma rays, etc.

  11. Essential: ultraviolet light (UVB), full spectrum visible light, Schumann waves (eg. 7.83 Hz), etc.

  12. Trauma / Injury:

  13. Acute: penetrating, lacerating, blows, crush, avulsion, obstructive, surgical, etc.

  14. Chronic: over use, over exercise, etc.

  15. Miscellaneous:

  16. Barometric Pressure - altitude sickness, barotrauma.

  17. Thermal - hypothermia, hyperthermia.

  18. Acoustic trauma.

And I think that just about summarises most causes.  All disease is caused by one or more of the above - and if the cause of a disease is not primarily inherited then it is due to psychological factors, altered sensitivity and/or one or more of the environmental factors listed.  In practice if one identifies and corrects as many of these as possible, health problems improve.  On the following pages I briefly discuss each of these major environmental categories.

Generalisation vs Individualisation

As a species, we have many common needs, susceptibilities and sensitivities - we can generalise about what is beneficial or harmful for most of us, most of the time.  But we are also on a steep learning curve with regard to this.  It appears to be like many things in life - you don’t realise how important something is until it changes.  Should we really be surprised how vital our diet is to our health?  Can we really expect that changing our environment so drastically isn’t going to have major repercussions?  The more we clean up our act, in as many areas as possible, the healthier we will be.

We are also unique individuals, each with our own specific needs, susceptibilities and sensitivities - not just psychologically, where it is perhaps most obvious, but also physiologically and biochemically.  The reasons why any one of us suffers ill health is because of the specific mix of causes which are peculiar to us.  If we are to regain health as rapidly as possible, the ideal should be to identify and address as many of the causative factors as possible.

Responsibilities for Health

As a species, we have many common needs - it is relatively easy to generalise about what is beneficial for most of us, but we are also unique individuals, each with our own specific requirements and sensitivities.  Our health is our own responsibility - as individuals we each need to find the right balance for ourselves.  In fact the presence of symptoms can be used as an indicator that we have not found the right balance.  We must also take responsibility for influencing national and international policies relating to the state of our environment.  We can control to a large extent where we live, what we eat, how much exercise we take and many of the toxins we introduce into our homes and bodies - but we have less direct influence on airborne toxins (eg. the siting of waste incinerators, pesticide usage, traffic fumes) and microwave exposure.

Ecological Management of  Health and Disease

In practice we find that most health problems tend to improve (and are prevented) when you address each of the above causative factors:

  1. Diet & Nutrition

  2. Exercise

  3. Sleep Insufficiency

  4. Psychological / Stress Factors

  5. Bugs: bacteria, fungi, viruses, parasites, etc

  6. Toxins

  7. Electromagnetic

For more information, see:       Health Essentials       Medical Management


  1. See: www.sehn.org/ecomedicine.html  - gives a nice overview of some basic principles of ecological medicine

  2. Environmental Medicine - Beginnings and Bibliographies of Clinical Ecology.  Randolph TG. Fort Collins, Colorado, Clinical Ecology Pub. 1987

  3. Environmental Medicine in Clinical Practice, by Anthony H, Birtwistle S, Eaton K, Maberley J.  BSAENM Publications 1997  IBSN 0-9523397-2-2

  4. Practice Information Sheets

Not all ecological medicine pages yet complete - apologies, but coming soon!


What is Ecological Medicine?

  ECOLOGICAL MEDICINE:  Overview   Nutrition   Allergy   Microbes   Toxins  EMR

  Ecological Medicine:         Overview          Health Essentials          Medical Management