In the last article on posted only last night on:
The Profession of Nutrition vs The
Role of Food Scientist in Research and in Industry
https://scientificlogic.blogspot.com/2023/07/the-profession-of-nutrition-vs-role-of.html
I briefly went through all the various sciences that touched on food and
nutrition.
I mentioned the practice of nutrition is now a regulated profession like
medicine, and like a doctor who does not specialize, he works as a general
medical practitioner, a jack of all trades, master of none. The same is said of
a nutritionist whose university training in this nutrition is very broad-based.
He knows in some depth the chemistry of foods, biochemistry and metabolism,
food analysis, food microbiology, food toxicology, basic medicine with
specialization on nutrition deficiency diseases and their diagnosis. He also
studies how food consumption is conducted, how nutrition status is assessed
using a wide battery of measurements. He has to deal with a wide range of
subjects just like a medical student who has to deal with a wide range of
diseases, their diagnosis and management.
Armed with a wide range of training he works as a nutritionist, jack of
all nutritional trades, master of none. His training is so broad-based that he
can fit into any job besides being a nutritionist. He gets all his knowledge
from the nutrition and or food scientists who conducts in depth studies on the
composition of foods which may or not only necessarily include only protein,
fats and carbohydrates sometimes referred to as proximate principles, how
they are oxidized in the body to yield energy to meet body needs, but other
components of foods. It may not necessarily include only vitamins,
minerals and trace elements but also other bioactive principles that have
medicinal and therapeutic properties.
A nutritionist will also have
training in the analysis of foods containing these proximate principles as well
as vitamins and minerals to establish the food composition table. For instance,
he may decide to weigh a small amount of food, determine its protein content by
using the Kjeldahl method. Most proteins contain 16% of nitrogen, thus
the conversion factor is to multiply the nitrogen content by 6.25 to obtain the
protein content.
However, the nitrogen from
nonprotein additives or contaminants in the food, such
as melamine in milk, is also measured. He may then use the
traditional Soxhlet extraction of oil using petroleum ether for the extraction
of fats and oils. He then subtracts the protein and the fats from the total
weight to give the carbohydrates, collectively known as “proximate principles”,
ignoring the much smaller amounts of vitamins, minerals and trace elements in
them.
If his training in analytical
chemistry is advanced enough, he may even use multidimensional gas
chromatography, or even using the nuclear magnetic resonance (NMR) analyser
to elucidate the organic structure of the other non-food but bioactive
principles in them, collectively known as the phytochemicals.
It all depends on the nutritionist
level of training in analytical chemistry and the university where he was
trained.
He may then proceed to determine
the caloric value of the food by using the bomb calorimeter. For vitamins there
are a wide range of analytical methods for each of them available to him. For
example in determining potassium, sodium, calcium and other metallic
elements, the nutritionist has at his disposal the atomic absorption
spectroscopy. The nutritionist as well as the food scientist is well-trained in
food analysis as far as the proximate principles (carbohydrates, proteins and
fats) is concerned as with the rest of the nutrients.
But over the years nutrition and
food scientists have discovered more and more other food principles such as the
tens of hundreds of thousands of phytochemicals especially in plant-based foods
other than the proximate principles, vitamins and minerals not known previously
to a practising nutritionist, let alone his ability to detect and to analyse
their composition.
He may only be able to study their
effects on the human body both for their preventive and curative properties, but
he may not know how they work. These are called functional foods beyond their
nutritional values. They have medicinal and therapeutic properties that even
dieticians have little training and knowledge. Their analysis and detection are
beyond the expertise of both the nutritionists and the dietician. They need to
call in the analytical chemists who are armed with their wide range of
analytical procedures. These nutrition and food scientists use a wide range of
analytical procedures such as the use of spectroscopy meters that include
infrared (IR) spectroscopy, far-infrared spectroscopy,
ultraviolet-visible (UV/Vis) spectroscopy, Raman spectroscopy, including
nuclear magnetic resonance (NMR) spectroscopy, x-ray spectroscopy, let alone
various types of chromatography such as gas chromatography, high-performance
liquid chromatography, thin-layer chromatography, and paper chromatography to
do the analysis.
Using these analytical procedures
are beyond the training, skills and expertise of a practicing nutritionist or a
dietician just as much all the advances in medical sciences like genomic and
molecular medicine, immunology, virology, Darwinian medicine, radiochemistry,
etc, etc are far beyond the knowledge of a medical doctor who is basically a
clinician doing clinical work. A clinician often uses lab support for a
definitive diagnosis, and these supports are given to the clinician through the
knowledge of biomedical sciences.
In order to practise advanced
medicine a clinician needs the qualified expertise of the medical scientist to
help them with the diagnosis other than merely taking medical history, clinical
examination such as palpation, percussion and auscultation with a stethoscope.
These include blood and urine analysis or by radiological imaging.
But if a nutritionist intent to
investigate the effects of food on health and disease beyond what they already
know on nutritional deficiency diseases, they need the support of the
clinician, nutrition scientist, the food analytical chemist, the statistician to
design the study, epidemiologists perhaps to look at disease patterns before
and after the study.
They may include animal and
laboratory studies, case-control, longitudinal cohort studies and randomized
feeding and clinical studies and epidemiology studies.
Cohort Studies:
A cohort is a group of people, so
cohort studies look at groups of people. A cohort study follows the group over
a period of time.
A research team may recruit people
who may or may have a certain disease under investigation. They collect all
available information about them for a number of years. The researchers see who
in the group develops a certain disease, and who doesn’t. They then look to see
whether the people who developed a disease had anything in common.
Cohort studies are very useful ways
of finding out more about risk factors. But they are expensive and time
consuming. They can be used when it wouldn’t be possible to test a theory any
other way.
Case control studies work the
opposite way to cohort studies. The research team recruits a group of people
who have a disease, and a group of people who don't as controls. They then look
back to see how many people in each group were exposed to a certain risk
factor.
Researchers want to make the results as reliable as possible. So, they try to make sure the people in each group have the same general factors such as age or gender.
Case control study may show that people with a lower income are more likely to develop a certain disease. But it doesn’t mean that the level of income itself causes the disease. It may mean that they have a poor diet or are more likely to smoke. In clinical and medical research there are many types and classes of studies. They depend on our study design. Just to give examples of some of them are, besides lab studies involving the use of animal models as well.
Case control studies are useful, and they are quicker and cheaper than cohort studies. But the results may be less reliable. The research team often rely on people thinking back and remembering whether they were exposed to a certain risk factor or not. But people may not remember accurately, and this can affect the results.
Another issue is the difference between association and cause. Just because there is an association between a factor and a disease, it doesn’t mean that the factor causes the disease. In humans we have:
Cross sectional studies are carried
out at one point in time, or over a short period of time. They find out who has
been exposed to a risk factor and who has developed a certain disease. They see
if there is a link.
Cross sectional studies are quicker
and cheaper to do. But the results can be less useful. Sometimes researchers do
a cross sectional study first to find a possible link. Then they go on to do a
case control or cohort study to look at the issue in more detail.
Longitudinal Studies:
Then we have longitudinal studies
involving cohorts designed to discover relationships
between variables that are not related to various background
variables. This observational research technique involves studying the same
group of individuals over an extended period. An example is the Framingham
Heart Study which is a longitudinal
cohort study that started since 1948 and has been followed up among cohorts
over the generations. That study is where we get our idea about cholesterol and
heart disease. But as that study was followed up over the years the same
Framingham Heart Study withdrew their same cholesterol and heart theory, but
the Big Pharma that produces those statins group of drugs to lower down blood
cholesterol levels did not wish to listen as it was a multi-billion-dollar
industry for them.
All these new discoveries and new
knowledge are far beyond a nutritionist or a medical doctor to accept. They
stick on to old textbook knowledge.
Nutrition research to evaluate just
one component of food on health and disease is a teamwork effort utilizing the
expertise from various disciplines of sciences. They may include anthropometry,
sociology, food and nutrition sciences, food consumption studies, food
toxicology, medicine, chemistry, biochemistry, food analysis, clinical
examination, among a host of others depending on the nature and scope of the
study. They all have to work together in coordination as a scientific and
medical team.
Intensive and Extensive Research:
Nutrition research is far from being easy. It is not like practising medicine or practicing nutrition, or dietetics.
I have much, much more to explain, but we shall give just a very brief look at the scope of nutrition research. In fact the research expenditure for nutrition is the highest among all the medical disciplines, amounting to over US $ 100 billion a year globally resulting in an avalanche of new knowledge published in tons of research papers on nutrition each year, and yet we have so much to learn the impact of food and nutrition in the prevention and treatment of all these chronic lifestyle, especially dietary lifestyle diseases which plague the affluent society globally for which we have no definitive answer.
Nutrition is so complex and
confusing that health companies and individuals every now and then make health
claims that this and that food can cure cancer, blocked arteries, neurological
diseases and stroke, arthritis, kidney, liver and lung diseases for which even
the most qualified nutritionist or a nutrition researcher has no clue. They
merely claim with an impressive list of foods that can ‘cure’ this and that
disease without showing any evidence that can only come about from any
well-designed and well controlled study. They just make personal claims from
personal experience, all mixed up with the medical treatment they were already
receiving.
Health and Labelling Claims:
Then we also have health food
manufactures making all sorts of health claims about their products and label
them as a cure so much so, nutritionists are very alarmed. So, nutritionists as
health professionals set up committees to advise the Ministry of Health and
other legislative authorities to enact food laws on health and labelling claims
on their products.
Food Additives:
The same, nutrition scientists and
food toxicologists conduct studies on food additives, food colours, food
flavours, food preservatives on the safety and long-term toxicity of some of
these food substances added to the food by manufacturers to enhance their
acceptability, keeping quality for commercial reasons. These scientists conduct
costly and long-term toxicological studies on these food additives to advise
the nutritionists their effects on health. The nutritionists in turn advise the
government the maximum limits these additives are allowed for safety. The
government in turn enact food laws such as the Food Act 1983 and the Food
Regulations 1985 to ensure that the public is protected from health hazards and
fraud in the preparation, sale and use of foods and for matters connected
therewith. It is then enforced by the Ministry of Health and the Local
Authorities.
Personal vs. Evidenced-Based Claims:
For instance, a few days ago I
received a video claim that was going round in the social media from a male
patient suffering from cancer who did not even specify what type of cancer. He
claimed that papaya leaves had cured him of his cancer even though he received
chemotherapy at the same time. So, we do not know if it was the chemotherapy or
the papaya leaves that caused his cancer to ‘disappear’ as he claimed when even
highly qualified nutritionists and oncologists have no clue. How do we deal
with such problems from the public is very difficult for me to understand.
Just this morning I met a gentleman
at the bus stop who was a stranger to me. He saw my leg all wrapped up in
compression stockings. He asked me what happened to my leg. I explained to him
I have chronic venous stasis ulcers, and the mechanisms why and how this
happens. He took out a small label of some herbal remedy which I can buy from
the Chinese medical hall. He told me this herb will solve my problem. Of
course, I did not offend him that it will not work because mine is a mechanical
(surgical) problem best managed surgically and physically. I thank him of
course for his suggestion.
We can see lay people make all
kinds of claims without showing the thinnest of evidence let alone large scale
RCT (randomized clinical trials), case control studies, cross sectional or
longitudinal cohort studies I mentioned above. But at least there must be some
minimal evidence serving as a springboard for large scale studies. For instance,
as described below about cukur manis.
Papaverine in Cukur manis As Evidence-Based:
Let me now illustrate an example.
In the beginning of 1970’s one of my Readers in Nutrition (Senior Lecturer /
Associate Professor as they were called in the UK) from the University of
London came over to Malaysia at the invitation of the National University of
Malaysia (UKM). UKM wanted to establish the Faculty of Medicine here in Kuala
Lumpur. My Reader was invited as a consultant to UKM on how to go about this.
I met him when one of the
professors from UKM contacted me. I invited my Reader from London for lunch and
during our luncheon conversation he mentioned about one of the staff from UKM
who went to London University to do a postgraduate course in nutrition like I
did in the early 1960’s. He told me this particular student told him (my
Reader) that there were reports from villagers here in Malaysia having fainting
spells when they ate a certain vegetable. My Reader asked this student, who is
a doctor, to send samples of this vegetable to him.
The doctor from UKM did. They at
London University identified it as Sauropus androgynus which is cukur manis in
Malay.
But why and how did cukur manis
cause fainting spells? Nutritionists at London University did not know. So,
they sought the help of their colleagues, the analytical chemists working in the Department of Chemistry of
the same college (Queen Elizabeth College) to analyse what inside cukur manis.
So, the chemists from the Dept of
Chemistry at Queen Elizabeth College did by using their powerful Nuclear
Magnetic Resonance (NMR) spectroscopy. They identified the compound present in
the cukur manis as papaverine, and it was this that caused the fainting spells
among the villagers.
Papaverine is an opium
alkaloid, primarily used as an antispasmodic drug and as a cerebral and
coronary vasodilator. It has vasodilating on the blood vessels, causing
the blood pressure to fall when taken orally, and hence synoptic (fainting)
effects of papaverine. It was a drug used in the Mediterranean to treat
high blood pressure. There you are. The analytical chemist had used their
discovery to provide knowledge to the nutritionist to explain the cause of the fainting.
The nutritionist would know this if the chemist had not analysed the unknown
compound in the vegetable.
In turn the nutritionist can advise individuals with high blood pressure to consume cukur manis in small amounts for this medicinal effect.
However papaverine can also cause serious side effects such bronchiolitis obliterans and damange to the lungs if consumed in large amounts. But if cooked properly it seems safe for consumption since it is also very rich in provitamin A, the carotenes, vitamin B and C, protein and minerals especially iron. It is probably one of the best vegetables nutrition and medicinal-wise in moderation.
The nutritionist in turn would pass this knowledge to the practising dietician to prescribe diets containing natural papaverine that can lower down high blood pressure, increase blood flow and not just lowering down their salt (sodium) intake to reduce blood pressure if consume in moderation.
This is just one example we learn that foods too have therapeutic properties, not just nutritive values. Most fruits and vegetables, especially highly coloured ones in the tropcs have very high medicinal and antioxidants properties, not just their provitamin A and vitamin C contents.
We can clearly see how scientists from different disciplines have help the nutritionist advance their knowledge with their discoveries to help each other. They then pass on their discoveries and knowledge to help society. We can see how this single, tiny bit of discovery on this vegetable as an example can serve as a springboard for larger scale randomized clinical studies. Each scientist in the research team contributing their wealth of scientific expertise to their research colleagues.We cannot work alone as if we are the only expert in the entire world. We need the expertise of our colleagues working in another field to help us when we do not know. We cannot be arrogant and self-centred. Even in research we work as a team. We cannot work alone. We form a committee, a team of experts from different disciplines of sciences or medicine sharing our ideas together to solve problems together. They may have better ideas than us. To claim we know better is morally, socially, ethically distasteful to a decent society.
Food as Medicine:
The same we may say of individual
and traditional claims that certain foods have medicinal and therapeutic
properties. Curative properties are not just drugs and medicines from
pharmaceutical companies.
Some 2,300 years ago the Greek
physician Hippocrates, considered as the Father of Medicine, already told physicians
during his time “Let Food be Thy Medicine”. He never said let medicine be thy
food? This was put into his mouth long, long after his death by drug companies,
probably by doctors too influenced by the very powerful and influential
pharmaceutical companies in the west and in the United States to promote their
drugs as medicines instead of food.
We never know which foods, especially all the highly coloured fruits and vegetables, have medical properties, not just nutritive values since we are dealing with tens of thousands, if not hundreds of millions of phytochemicals in plants. There is no way for any nutrition scientist to help the nutritionist to screen all those untold numbers of fruits and vegetables.
Nutritionists now label them as
“functional foods” – foods that serve beyond just nourishing the body – foods
that serves as medicines for tens of thousands of years since the time of Adam
and Eve in the Garden of Eden where God told them they may partake from every
tree of knowledge in that Garden that would have given them health and eternal
life, except one tree, the tree of evil. There is a herb for every illness on
earth
Does that message ring the bell?
Nobel Prizes in Medicine for Scientists None for Doctors:
It is no surprise that all the
Nobel Prizes in Medicine or in Physiology went to the medical scientists rather
than to the medical doctor since 1927. It was the scientists in biomedical
sciences who contributed almost 99.9 % of their discoveries and knowledge to
the medical doctors and nutritionists to educate, practise and apply them on their
patients.
I think I need to stop here to
rest, else it never ends. It will run into chapters all through the night till
dawn into days should we continue to write.
We can learn from each other,
as much as a doctor or a nutritionist can learn from other biomedical
scientists.
Thank you for reading.
Lim ju boo
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