How a Debate Between Two French Scientists in the 1800’s Shaped Modern Medicine Forever

In the 19th century a French debate raged between two of the eras biggest intellectual heavyweights that would determine the way practiced medicine for the last 150 years, and still do to this day.

The 19th Century

In the 19th century a French debate raged between two of the eras biggest intellectual heavyweights that would determine the way practiced medicine for the last 150 years, and still do to this day.

The combatants were biologist, microbiologist and chemist Louis Pasteur, and renowned scientist and organic chemist Antoine Béchamp.

The debate revolved around the cause of disease and the respective positions went something like this:

Pasteur believed that as disease was caused by pathogenic microbes in the form of bacteria and viruses entering the body and wreaking havoc on physiology resulting in disease. Finding ways of killing these organisms would be the root cause of preventing or curing disease.

Though Béchamp was on board with the idea that pathogenic microbes could cause disease, he hypothesized that these organisms were ever-present throughout human history and it was not exposure to the pathogen that caused outcomes, but the health of the host. He, therefore, believed that to prevent disease the host should be made as healthy as possible through diet, lifestyle, and hygiene practices.

It was in fact Pasteur who won the debate. This led to ‘germ’ theory where medicine focused on the eradication of pathogenic organisms as disease treatment (the process of pasteurisation that eradicates microbial organisms from food by heat-treating them is named after Louis Pasteur) (1).


Was Pasteur Right?

He was, partially, but not entirely.

The historical backdrop to this debate was the rapid industrialisation of Western Europe which saw with it a sharp rise in infectious disease as people lived in increasingly crowded conditions as migration from rural to urban areas increased.

If you go to any graveyard over 100 years old within the UK, you may notice lots of headstones for people under 40, often children and sometimes whole families died within a few days of each other – this was most likely tuberculosis. Tuberculosis is a lung infection caused by Mycobacterium tuberculosis within cities in the 18th and 19th centuries. Its spread had reached pandemic proportions with infectious diseases being the leading cause of death (2).

Taking this into consideration, it’s possible to see why Pasteur’s hypothesis may have been more convincing at the time.

Germ theory also led to advances in medicine that we all benefit from today. The discovery of penicillin in 1928 lead to the development of antibiotics and vaccines, which meant by the 1960’s infectious disease was now a minor cause of death and child mortality had plummeted.


The medical model was developed extremely well around this acute form of care. Vaccines were preventative and if you got an infection, you would take antibiotics which would kill the pathogen and you would be cured (3).


So Pasteur was definitely right then?

As stated before – not entirely.

Science is designed to only answer one question at a time. Human beings like ‘one-solution-answers’, and this can lead to a reductionist approach in any discipline. The example below is a case to expand on this point.

Infectious disease is no longer the biggest killer in developed countries; instead, we have a chronic disease epidemic with steep increases in obesity, diabetes, and resulting metabolic dysfunction. The leading cause of death is now heart disease for which we now know that metabolic health plays a role in the pathogenesis of this disease (4).

Despite this the way we treat disease has not pivoted, instead, if you are found to have a chronic disease whether it be metabolic, autoimmune, or even mental, you are offered a drug which may provide relief to some of the symptoms caused by the issue, but unlike antibiotics in a bacterial infection, does not cure it.

This is not to say these drugs have no use, but it means that your chronic issue, which may have developed through any number of variables of interplay between genetics, environment and lifestyle, is ‘bandaged’ over and not really dealt with. This will primarily mean a reliance on that drug (if it is effective) but also does not mitigate risks of other issues that may be caused by the original problem which may in themselves need further medication.

The ‘acute’ style of care works extremely well for infections… but for chronic conditions – not so much.


The host’s health is the most important factor in chronic disease

Now pathogenic infections are not our main health concern, it is clear to see that the health of the individual significantly increases or decreases risks of chronic disease. This is not just related to aging. In fact, we’re not living much longer now than before, but we are living with an increased disease burden (see blog on Ancestral Nutrition) (5–7).

This does not only apply to non-infectious disease, Weston A. Price noted in his travels during the 1930’s observing health differences between peoples living both pre and post industrialised lives, that rates of tuberculosis were virtually non-existent in people living and eating in a way that way consistent with their pre-industrial ancestry. The recent COVID-19 pandemic has illustrated this with 90-99% of all patients hospitalised with the disease also having conditions associated with metabolic dysfunction (8–11).


The Future

Now we know this why do we persist with the current health care model when it was designed for different challenges than today?

Well, it’s important to remember that our current health care challenges have only been the case for about 50-60 years or so. The healthcare industry is a multi-billion dollar industry with major corporations and governmental involvement and regulation. A beast like this has an enormous turning circle and it will likely be a very long time before any significant change is considered.

There are those who believe that necessity will drive change as the obesity, metabolic dysfunction, and type 2 diabetes epidemics presents a growing problem that’s outstripping the pace of drug-based solutions, presenting developed nations with a healthcare bill that no system will be able to afford (12,13).


Is there a Solution?

None of this helps much if you have a chronic disease and want to act now. So what can be done?

Functional medicine is an alternative health care model where the body is viewed as it works physiologically, which is a number of systems all working together and having an effect upon each other i.e. digestive system, immune system, cardiovascular system, neurological system etc. (see What is Nutritional Therapy).

Essentially by ensuring the bodies systems are working together as optimally as possible gives the best chance for preventing, mitigating or in some cases reversing disease risk. Though this way of working is not yet mainstream, practitioners do exist that practice with this model who stay abreast of the latest science-based updates and are not shackled by the reductionist procedure of conventional medicine (14).

In summary, if you have a broken leg, a heart attack, infection or are in a car accident, the current healthcare system has evolved to be extremely well designed to best help you in these situations. However, what about your cardiovascular disease risk before you have a heart attack? Or an autoimmune disease? Or type 2 diabetes? In these instances, considering a functional approach would give better long term outcomes.

On his death bed Pasteur is reported to have said “the microbe is nothing, the terrain is everything” insinuating that he came around to Béchamp’s original hypothesis in the end. Though ‘germ theory’ and the work of Pasteur has given us some wonderful medical advances, it would be naive to presume that this one solution problem is the answer to everything (1).


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