What is Clinical Nutrition?


Clinical Nutrition is the scientific study of the relationship between food and health.


It may also be considered as the science of nutrients and how they are digested, absorbed, transported, metabolized, stored and eventually eliminated by the body. Besides studying how food is processed by the body, nutritionists are also interested in how the physical environment (i.e. soil & water quality, farming practices e.g. crop spraying & the application of fertilizers) affects the quality and safety of foods and what influence these factors have on both health and disease.


Australian soils for example are typically low in iodine, selenium & molybdenum, whilst being rich in sodium and boron. These statements are admittedly a generalisation; however the quality of the food you buy depends very much upon where the crops were grown, together with the agricultural practices involved in crop production. For example, whether the food was grown organically, hydroponically or conventionally significantly affects the nutritional value of the resulting produce.
















What are Nutrients?


Nutrients are substances that the body needs to live and grow. The body requires several dozen different sorts of nutrients, and the ways they are used are as different as the molecules, cells, and tissues they help to create. Carbohydrates (carbs), proteins and fats -- called macronutrients -- are broken down (metabolized) to provide energy. Vitamins and minerals -- called micronutrients -- are not used for energy themselves, but are needed to assist those enzymatic processes that enable the body derive energy from the food we eat.


In an ideal world, we would be able to attain all the nutrients we require for optimal health & well-being from a wholesome, balanced diet alone. And to a certain extent, that goal is theoretically achievable. But in reality, there is probably no-one on this planet at this present time to whom this utopian vision could truly apply.


Enter the concept of biochemical individuality.


This is a concept derived from research in genetics, biology, biological chemistry and clinical medicine whereby each individual is regarded as being biologically unique, even to the extent that so-called “identical” twins are not biologically identical after all! Yes, they may share an identical set of genes at conception, but that’s where their biochemical paths begin to diverge as nutritional & environmental factors being to imprint their influences upon the expression of their genetic code. These influences are termed “epigenetics” and as such have a great deal of influence upon how our bodies function at a cellular level.


What do Clinical Nutritionists do?


Well, lots of different things! Some work in Universities either teaching

or undertaking research programs; some work for the CSIRO or other

semi-Governmental organisations; some work in Industry whilst others

(like myself) choose to work in private practice. However, regardless of

where they choose to work, they all share the fundamental belief that

good nutrition benefits both the individual and the community as a



What then is Nutritional Medicine,

and how does it differ from Clinical Medicine?


When you go to the Doctor (GP), he or she will want to know why you

have come to see them. Is it a social visit (not usually); you were just

passing by and thought you might just “drop in”; do you need a

“check-up” or is there something actually troubling you? Such troubles

are called symptoms, and various patterns of symptoms tend to suggest

particular diagnoses. Sometimes the diagnosis is readily apparent

(e.g. a broken arm), whilst at other times further investigation is

required. However, often the presenting symptoms lend themselves to a

particular diagnosis (or a label such as hypertension), which doesn’t

actually tell you anything about the underlying cause!


Let’s take Mary for example.


Mary is (or was) a spritely 84yr old who has lived with her pet cat

in a retirement village for the last 6 years since her husband died.

She is normally pretty independent and still drives her car to do her

shopping and see her friends.

Well, one day she trips over an electrical cord on the ground

and breaks her ankle. Despite many protests, she is carted off to the

nearest public hospital for an X-ray, which duly reveals the cause

of her trouble.


Or does it?


Yes, the X-ray may show a spiral fracture of the lower fibula,

that may require either a below-knee plaster for 6-8 weeks

or may be bad enough to require an orthopaedic surgeon

to stabilize the joint with some surgical plates & screws

at an operation.


But does a diagnosis of a fractured fibula tell us anything

about the underlying causes of her predicament?

For example:


 - Could it be that she wasn’t looking where she was going and had

forgotten to wind up the cord of the vacuum cleaner after she had finished the vacuuming?


 - Or could it be that she is developing macular degeneration; the commonest cause of blindness and visual impairment in Australia, and therefore didn’t notice the cord was lying across her path?


 - Or could it be that her bones are becoming osteoporotic (thinning out) because of her lousy diet and incessant cigarette smoking for the last 40 years? And thin, old bones do break pretty easily!


Or could it be a combination of these as well as several other factors?


You see, Clinical Medicine is very good at fixing broken bones. It might even pretend that some new whizz-bang drug, if taken continuously for 30 years (and somehow miraculously you don’t develop a serious side-effect of such consumption), can stop your bones disintegrating even further. But it cannot address the underlying problem(s). That requires someone who understands human nutrition thoroughly and understands the biochemical processes that ensure that old bones will inevitably break apart, sooner or later, unless all of the nutritional, hormonal & lifestyle factors that predispose to osteoporosis (and osteomalacia) are thoroughly evaluated & remedied.


Nutritional Medicine applies the findings of scientific research to deal with the underlying causes of such occurrences.


So, in Mary’s case, the Clinical Nutritionist would take a detailed history of what happened, talk to her about her eyesight and co-ordination, maybe even check out her memory to uncover any evidence of early signs of dementia. They would also take a detailed dietary history, as well as inquiring about things like cigarette and alcohol consumption and drug use – both prescription medication as well as over-the-counter drugs.


He (or she) would want to know about what tests had been performed at the hospital, or at subsequent follow-up consultations, as well as what measures had been instituted (if any) to prevent a repeat of the performance.


The Nutritionist may then arrange a whole series of tests that her conventional doctors would not have thought of.....................................................


Things that directly relate to bone integrity, visual acuity

and co-ordination just for starters. Perhaps she had become

diabetic without knowing or telling anyone, and her eyesight

had deteriorated accordingly.


Perhaps she was still depressed from her husband’s death

(which she quietly hid) and so would just eat whatever was

quick,  easy and didn’t require much cooking. Perhaps she had

resorted to her old friends: alcohol and cigarettes, to cover her

loneliness and sense of abandonment.



And so, much of what a Clinical Nutritionist does is detective work – trying to uncover the underlying causes and mechanisms (pathogenesis) of a particular illness.


It is very individual/client-oriented, and does not invent “one size fits all” remedies. Treatment recommendations are tailor-made for that particular individual, in that particular situation, at that particular point in time.


Such recommendations would normally include some dietary changes or “food plan”, nutritional supplements to provide particular nutrients that were found to be in short supply, or even some lifestyle modifications that would engender a happier and healthier life.


You see, I’ve been on both sides of the fence!


From conventional GP for many years to Clinical Nutritionist, with various other interesting jobs in between. I could not do the sort of work l now do without my conventional medical training. But likewise, l would not now willingly practice conventional (pharmaceutical) medicine, knowing what l now understand about the fundamental inter-relationships between nutrition and health.


So, life’s a bit of a journey, one to be savored and reflected upon. Each day we learn something new about ourselves, or how the world works or what works for us, to improve our health & well-being.


A process of discovery........................................................