Dr Charles Forsyth

Ecological Physician


We share our environment with countless billions of microorganisms - without them life on our planet would cease.  Those in the soil are absolutely vital to the health of plants, including those that we eat.  There are nine times as many bacteria in our intestine (our intestinal microbiome or gut flora) than we have cells in our body - and the correct balance is absolutely vital for our health.  However, as we all know, there are also plenty of organisms that cause disease, we call them “pathogenic” organisms. 

Our body has many amazing mechanisms to stop pathogens invading it and to kill those that do breach it’s defences.  A healthy immune system is constantly vigilant, constantly deciding what is “foreign” and therefore bad for us and requires elimination, and what is “self” and therefore acceptable.  The best protection against infections is good robust health.

When we catch an infection it is the result of one or more of the following:

  1. A weakened immune/ defence system - and this is the cause 95% of the time!

  2. An unusual breach of the defences (eg. deep dirty wound, contaminated blood transfusion, etc).

  3. An overwhelming exposure to and/or a particularly virulent organism.


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Five key things:

  1. Avoid exposure where possible - be sensible about cleanliness & hygiene and exposing yourself to at-risk environments. 

  2. Live as healthy a life-style as possible (see below).

  3. Be actively involved in improving/resolving all your (& your family’s) health problems - consult professionals to help you attain optimal health.

  4. Use specific preventative measures when and where appropriate. 

  5. Treat infections effectively:

  6. Address the causes of your weakened immune system.

  7. Use antimicrobials when appropriate - whether natural or synthetic.

PREVENTION - How To Strengthen Your Immune System

First things first - always try and treat causes!  If you suffer with recurrent infections seek to identify the causes and make sure you address these.  The health of our protective barriers (skin & mucous membranes) and immune system are hugely affected by all the following factors:


Make your diet the best it can possibly be - fresh, natural, wholefood, vegetable dominated, minimal sugar & additives, relatively low starch, as nutrient dense as possible, plenty of protein, as much organic as possible, etc.  See Nutrition for more info.


Take plenty of regular physical exercise, (however over-training can impair immune function).  See Exercise for more info.


Get enough good quality sleep, for most of us this means 8 hours. See Sleep for more info.


Minimise stress by good self-pacing, regular rest periods, realistic & appropriate expectations, relaxation exercises, identifying and dealing with the causes, etc.  Be happy & positive - ensure that your life regularly/ frequently includes those things that are most important, fulfilling and nurturing to you.  Remember that how well we cope with the stresses in our lives is also hugely affected by all the other health influencing factors in this list.  See Psychological for more info.

Gut Health

In addition to an excellent diet, eat live yogurt or kefir (easy to make yourself) or take a probiotic, especially after antibiotics; avoid antibiotics whenever possible and ensure excellent bowel function.  Remember that the more tense and stressed we are, we are much less likely to produce enough digestive enzymes or stomach acid to digest our meals - and these are essential not only to ensure optimal nutrition but also to kill off the organisms we swallow in our food or the mucus we  produce during a respiratory tract infection.  See Dysbiosis, Pancreatic Enzyme Insufficiency & Hypochlorhydria (low stomach acid) for more info.

Toxin Exposure

Minimise tobacco, alcohol, chemicals (at home & at work) and drugs.  Toxins, by definition, interfere with, block or put increased demand on our biochemistry.  Our body is a wonderfully complex biochemical machine - for optimum health we need optimum biochemistry - which in turn is dependent on every other factor in this list, especially nutrition as that is the source of the raw materials for the biochemical machinery.  See Toxins for more info.

Nutritional Deficiencies & Supplements

Nutritional deficiencies are very very common - either because of poor diet/ nutrient intake or poor digestion/ absorption - both of which are very very common! Obviously the most important thing to do is to identify and resolve both of these but until this is achieved nutritional supplements are usually required.

Vitamins A, C, D and K, and Zinc are particularly vital for immune function - so ensure a decent intake/ levels of each & all.

For anyone who has almost any health problems or who wishes to boost themselves in the short term to reduce susceptibility to infections, I usually suggest taking the following:

  1. A high quality Multivitamin and Mineral supplement, eg. One a Day (Biocare), Multi-Guard (Lamberts), VM75 (Solgar) for adults, or a suitable children’s multi for children.

  2. Omega 3 essential fatty acids, eg. for omega 3 take Fish oil 1000 mg twice a day or Flax oil 2.5 ml daily (if you take cod liver oil, this will provide enough vitamin A as well - but you will still need to take extra vitamin D).  Alternatively take an omega 3 & 6 oil blend such as Udo’s Choice oil 5ml daily.  For children between 5 & 12 years give half this dosage.  Eat plenty of nuts (not peanuts) & seeds - these supply mainly omega 6 EFAs, except for linseed, walnuts, pecans & pumpkin seed - which also supply omega 3 EFAs.

  3. Extra Vitamin D, eg. 2000 iu (50 mcg) daily (you may be able to leave it off when you have plenty of sun exposure to lots of your skin).  It is almost impossible not to be vitamin D deficient in the UK winter due to the lack of sunlight - everyone in the UK should take extra.  I have yet to see a multivitamin/mineral that contains enough - they still provide 400 iu or less.  Vitamin D is essential for immune function - and the lack of it is a large part of the reason for the prevalence of winter infections.  The dosage for children over 5 years is the same.  See: Vitamin D

  4. Extra Vitamin C, eg. 1000 - 3000 mg daily, preferably divided over the day; very few multivitamins/minerals contain this much.  During an infection this can be increased to ‘gut tolerance level’ (the maximum dose you can take without developing loose stools), taking a large dose every 2-4 hours.  Any form is fine, ascorbic acid powder is the cheapest, but if you are susceptible to stomach ulcers/ acidity, use magnesium or calcium ascorbate.  If you develop loose stools adjust the amount and frequency so that you are taking the maximum you can tolerate and afterwards take probiotics.  Vitamin C is anti-microbial.  For children over 5 years, give half this dosage.

  5. Extra Zinc, eg. 15 mg daily for several months.  Most multivitamins/minerals contain up to 15 mg zinc - so this is in addition to that & most of us shouldn’t need to take 30 mg daily in the long term - unless we have an inadequate diet - or have problems with digestion/absorption in which case we may need more than the normal daily requirements are 15 - 30 mg.  If you have little white patches on your fingernails it usually indicates you are zinc deficient.  For children between 5 & 12 give 10 mg daily.  Zinc is far better absorbed if taken mid-way between meals, for most people the most convenient time is last thing at night.

  6. Iodine - see my information in the pages: Nutritional Supplements and Health Essentials.

  7. Extra Vitamin K.  Vitamin K plays vital roles in blood clotting, bone formation, the cardiovascular system and in cancer prevention. The areas to consider supplementation in include (for which other causes must always be sought): Bleeding tendencies (easy bruising, nose bleeds, gastrointestinal bleeding, heavy menstrual periods); Osteopenia/ Osteoporosis; Calcification of soft tissues, esp. blood vessels (atherosclerosis and hypertension) and heart valves; Cancer; Chronic inflammation, Chronic infections; and conditions where vitamin K intestinal absorption is impaired (eg. intestinal malabsorption (especially of fats), pancreatic enzyme insufficiency, dysbiosis, coeliac disease, food allergies, etc).  See my information sheet ‘Vitamin K’.  Good dietary sources include:

  8. K1:  Leafy Green Vegetables: Kale, Spinach, Collards, Swiss chard, Mustard greens, Turnip greens, Brussel sprouts, Cabbage, Parsley; also Broccoli, Cauliflower, Avocado, Kiwi fruit, Grapes, Soybean oil.

  9. K2:  Nattō is the richest of all dietary sources of vitamin K2 (mainly as MK-7); Fermented Cheeses are a rich source of vitamin K (mainly as MK-9, and next MK-8); Sauerkraut is also a rich source (mainly as MK-6 and also as MK-9); Meats, Eggs (esp. yolk), and Dairy products (esp. butter) (mainly as MK-4).

  10. A healthy Gut Flora (mainly E. coli) converts vitamin K1 to K2 (as MK-7).

  11. Vitamin K appears to be remarkably safe - there are no reports of any toxic effects of natural Vitamin K at 500x the normal dietary allowance; nor of K2 at 90mg/day!

  12. Dosage: usually between 200 - 5,000 mcg - the more severe your condition, the higher the dose (doses of 45mg are used for osteoporosis).

  13. My current favourite products is:  Super K Complex K1 & K2 2200μg (Fairvital; Vitamin K 2200μg, of which: Vitamin K1 1000μg, Vitamin K2 (MK-4) 1000μg, Vitamin K2 (MK-7) 200μg; + microcrystalline cellulose, hydroxypropylmethylcellulose, ascorbyl palmitate, L-leucine; 90 capsules, about £20).  Eg. from: www.amazon.co.uk.  This is the most cost effective product for this dosage that I have so far found.  Take one daily.

  14. Extra Vitamin A, eg. 10,000 iu (3 mg) daily for several months. This must not be taken by women during pregnancy or considering (or at risk of) pregnancy, esp during the first three months.  Few multivitamin/mineral supplements have more than 2000 iu these days because of this risk.  Current official guidelines are extremely cautious and recommend not having a long term intake exceeding 5000 iu (1.5 mg) - at least for long periods.  The Vitamin A recommended daily allowance (RDA) is usually set between 3000 & 5000 iu (900 & 1500 mcg).  But in reality vitamin A toxicity rarely seen at doses of less than 100,000 iu (30,000 mcg) - doses of 100,000 - 200,000 are routinely used by doctors for treating acne.


  1. Constitutional homeopathy - strengthens the whole system at a very fundamental level - the right remedy greatly improves your sense of well-being, energy, ability to cope, immune function and the vast majority of your symptoms because it has a deep multi-system strengthening effect.

  2. Specific homeopathic prevention - using homeopathic medicines that are specific to the infectious diseases you are trying to prevent.  There is a long tradition in homeopathy of the use of homeopathic medicines to prevent certain specific diseases, and the clinical impression of myself and many other homeopaths is that it appears to confer a very useful degree of protection.


The number of infectious diseases that can be prevented (even if partially) by immunisation continues to rise.  The duration and degree of immunity provided by a conventional immunisation varies according to the specific immunisation - some have a very high degree of efficacy and a long duration of action, some less so.  Most have the potential for causing side effects and this also varies according to the specific immunisation.  In addition to the live or dead organisms (or fraction of), all immunisations contain a variety of excipients which may include: thimerosal (a mercury compound), aluminium, formaldehyde, phenol, antibiotics, etc (see: www.cdc.gov/vaccines/vac-gen/additives.htm).  As with any intervention, one is always trying to weigh up the potential benefits versus the risks - and there is still considerable controversy regarding both for many immunisations.  Smallpox has been completely eliminated worldwide; some other diseases have been almost eliminated (tetanus, diphtheria) in immunised populations, and there is still controversy over to what extent others have contributed to reduction in infection, morbidity and mortality rates.


Infections - Overview

  ECOLOGICAL MEDICINE:  Overview  Nutrition  Allergy  Microbes  Toxins  EMR

  Infections:   Infections Overview    Influenza & RTI’s     Chronic Infections     Dysbiosis