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Health Items from 2010:
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photo, click on itExercise surprises Saturated fat was framed Old age supplements The magic bullet pill What are trans fats? Diabetes 1 Diabetes 2 Not all diseases are equal Diabetes 3 Stress kills A treatment for Alzheimers will be later rather than sooner Personalized medicine
Before I went to school, I didn't wear
shoes very often in the warm or hot weather. One year I had as a
surprise a pair of running shoes. They were called running shoes and
I was pleased with them and so when they were put on my feet, I ran.
I ran for a long time until I was unable to run any longer and so I
took the shoes off and carried them home. It became one of those
embarrassing stories that my parents told everyone.
But apparently, running shoes are not
the perfect thing for running. It seems they protect your feet at the
expense of your ankles, knees and hips. Comparing the forces on
joints when running barefoot or in running shoes, the running shoes
increased the hip internal rotation torque by 54%, knee flexion
torque by 36%, and knee varus torque by 38%. The increase is due to
the elevated heel and support under the arch in running shoes. A good
part of the strain on leg joints is due to the arch support.
When I have done my little walk with
the dog, I have used good running shoes in spite of noticing that it
was less tiring on my legs when I wore sandals. From now on I'll be
using the least rather than the most supportive shoes from my
walking. For as soon as it is not slippery out, I will be walking
Another lesson to learn is that when
one fasts and gets hungry, you get more alert and physically active.
We metaphorically start to hunt for food in a restless way. When we
are feed, we become inactive. We metaphorically curl up and digest
while we snooze. I have been walking immediately after lunch because
that was supposed to reduce the storage of fat. Maybe I should be
walking before lunch. Decisions, decisions - nothing is easy.
Saturated fat was framed
The latest news in 'don't trust
nutritionists' category: not all fat is bad for you.
We have been told that 'fads may come
and go, but trust me, saturated fat is bad for your heart. Period.'
Now we have a new prospective.
“Combined the results of 21 previous studies that followed 347,747
adults, aged 30 to 89, for five to 23 years (showed) 11,000
participants developed heart disease or suffered a stroke. Over all,
there was no difference in the risks of heart disease or stroke
between people with the highest and lowest intakes of saturated fat.”
That is not very good evidence for avoiding saturated fat. Doesn't
high saturated fat give high LDL cholesterol and high LDL cause
plaque in arteries?
Well it turns out that there is LDL and
there is LDL. There are small particles and large ones and the small
ones are the 'bad cholesterol'. Unfortunately, it is the large
particles that are associated with saturated fat consumption.
It also turns of that there is
saturated fat and there is saturated fat. The type of saturated fat
in meat and chocolate does not elevate LDL (large or small
particles). And further, the saturated fat in dairy products,
although it elevates LDL, also elevates HDL, 'the good cholesterol'.
And to top it off, it needs to be said that the partially
hydrogenated oil used to make the spreads that are promoted as
healthy replacements for butter may contain trans fats which are more
dangerous than saturated fat.
Rule of thumb: don't eat food made in factories with non-biological chemical processes.
Finally there is the question of
reducing saturated fat and not replacing it with other fat like
vegetable oil or fish oil. If there is any value to reducing
saturated fat, it is likely to be when it increases the consumption
of polyunsaturated fat and changes the ratio between the two types of
fat. Natural polyunsaturated fat is very healthy.
The most dangerous thing is to increase
carbohydrate as a replacement – something that is common when people try to reduce
saturated fat. Increasing carbohydrate can increase triglyceride fats
and LDL in the blood while decreasing HDL. Too much carbohydrate is
more likely to damage arteries than is too much fat.
Cutting animal or vegetable fats from
the diet also cuts the fat soluble vitamins, essential fatty acids
and other good things that come with them. Really starving the body
(as in anorexia) cause the body to convert larger areas of bone
marrow to make and store fat. This causes osteoporosis.
Old age supplements
A while ago I started to take vitamin
D. I now have run across some additional evidence that it was a good
“A team of researchers at Warwick
Medical School carried out a systematic literature review of studies
examining vitamin D and cardiometabolic disorders (cardiovascular
disease, type 2 diabetes mellitus and metabolic syndrome). ...
Researchers looked at 28 studies including 99,745 participants across
a variety of ethnic groups including men and women. (14 USA, 8
Europe, 2 Iran, 3 Australasia, 1 India and most between 2004 and 09)
The studies revealed a significant association between high levels of
vitamin D and a decreased risk of developing cardiovascular disease
(33% compared to low levels of vitamin D), type 2 diabetes (55%
reduction) and metabolic syndrome (51% reduction).
Vitamin D is a fat-soluble
vitamin that is naturally present in some foods and is also produced
when ultraviolet rays from sunlight strike the skin and trigger
vitamin D synthesis. Fish such as salmon, tuna and mackerel are good
sources of vitamin D, and it is also available as a dietary
I also found the components of a
supplement that has been tested on animals with very good results. I
think it is just a list of the popular supplements for the aged – I
have visions of some researcher asking grandmother what to buy and
putting all the pills together. At least some of the components are
working but who knows which. It might only be Vit D and a couple of
others for all we know.
Here is the list:
Vitamin B1 (thiamin)
Vitamin C (ascorbic acid)
Acetylsalicylic acid (aspirin)
Folic acid (vit B9)
Green tea extract
Cod liver oil
Flax seed oil
The magic bullet pill
Drug companies have been searching of
the magic diet pill – what a money making coup that would be. The
problem is not that they don't work: plenty of drugs cause weight
loss, at least for as long as you keep taking them. But
unfortunately, there's always a 'but'. Fenfluramine worked, but it
caused heart valve defects, and was banned. Sibutramine works, but
it's just been suspended from the European market due to concerns
over heart disease (a different kind). Amphetamine-like stimulants
such as phentermine work, but they're addictive and liable to abuse.
But maybe you remember (back in the
'60s) that marijuana gave you an appetite. Well the drug companies
have tried marijuana antagonists which block the cannabinoid
receptor. These should have the opposite effect and they do. But...
The cannabinoid receptor, which is
activated by the body's own naturally produced cannabinoid
neurotransmitters as well as marijuana, is very important to memory,
motivation, emotion, pain, hormone secretion etc. etc. The
endocannabinoid system is a general neural feedback system that
regulates all the other neurotransmitters at optimal levels. So
blocking this system gives people psychiatric problems like
depression and anxiety. Statistically CB1 blockers are more
consistant at giving depression than antidepressants are at treating
it. They (rimonabant, taranabant) are another diet pill failure.
Given the track record of diet pills, I
would not agree to be part of any trial.
What are trans fats?
Ordinary fat is made of three fatty
acid molecules bonded to a glyceride molecule (called triglycerides).
Each fatty acid molecule is a long string of carbon atoms with an
organic acid group at the end and hydrogen atoms along the chain
occupying the spare carbon bonds. When each carbon atom in the chain
uses two of its four bonding points for its bond to its neighbouring
carbons and the other two for hydrogen then the chain is called
saturated. This is the saturated fat found in meat and dairy
products. If one pair of neighbouring carbons have a double bond,
each uses three of their bonding points and leave only one for
hydrogen (called mono-unsaturated fat). If more than one pair of
neighbouring carbons double bond, we have poly-unsaturated fat. Most
vegetable oils are polyunsaturated. Other types of molecule that will
dissolve in these triglyceride fats are often also called fat, for
Saturated fat can be made in factories
from unsaturated fat by adding hydrogen in a catalytic process that
breaks the double bonds between carbon atoms to leave single bonds.
The change from unsaturated to saturated makes the liquid oil become
a solid like lard. The process can be only partially done (partial
hydrogenation) and this gives a fat with fewer double bonds but still
some, an unsaturated fat but less unsaturated then the original oil.
This is a solid but soft product with a consistency similar to
butter. It was thought better than butter because it had no
cholesterol and it was not saturated fat. (The consistency of butter
is due to its water content and other factors, and not due to
unsaturated fat.) As both saturated fat and cholesterol were
considered problems in the diet, partially hydrogenated fats were
But the partial hydrogenation process
created a new type of double bond that was not in the original oil.
There are two ways that the hydrogens can sit at a double bonds. It
can be thought of as the two being on the same side (called 'cis') or
on opposite sides ('trans'). The oils do not have 'trans' double
bonds, but it the process of hydrogenation, they are formed. The
standard way of partially hydrogenating oils produces fat that is 40%
trans fat. Biological systems make extremely few 'trans' fats. When
they do, the fats are conjugated making them chemically quite difference from
trans fats made during hydrogenation and they are not known to be
unhealthy. Biological systems cannot process trans fats – they just
have not the enzymes. Lipase, for example, the main enzyme that
breaks up fat, cannot deal with trans fats. Trans fats resist going
rancid. Trans fats are straighter molecules than cis fats because cis
bonds force a kink in the carbon chain. Cis fats are therefore softer
than trans. Because trans fats have ideal consistency, withstand high
temperatures, and keep well, they have been a favorite of the
processed and packaged food industry. The concerns about animal fat
and cholesterol have added to the popularity of unsaturated fat
including trans fats.
It turns out that trans fats are much
more dangerous than animal fats. Many medical organizations want
trans fats completely banned. A ban is now seen as the most effective
public health measure that can be take to improve cardiac health. Too
much saturated fat increases the LDL (bad cholesterol) in the blood,
but much small amounts of trans fats not only increase LDL but
decrease HDL (good cholesterol). Also some particular animal saturated fats
are almost immediately converted in the body to unsaturated fats (cis not trans)
and so do not raise LDL at all.
There is general agreement that trans
fat contributes to heart disease more than any other component of the
diet. Cardiac heart disease is roughly doubled for every 2% increase
in trans fat calories consumed in place of carbohydrate calories. It
takes a 15% increase in saturated fat to give the same effect.
Replacing trans fat with non-trans unsaturated fat decreases risk by
about a half.
As well as the proven case of heart
disease risk, there are a number of other suspected dangers to trans
fats: type 2 diabetes, Alzheimer's disease, cancer especially breast
cancer, obesity, liver dysfunction, infertility in women. The links
with these diseases are being studied to see if they are significant.
Many countries are moving to decrease
the use of trans fats and many food companies are reformulating their
products to lower the trans fat included. There are ways to reduce
trans that do not cost too much or lower the quality of food. Labels
including the amount of trans fat are also coming in more and more
For those products that are not labeled
there are rules of thumb. Any label that says 'partially hydrogenated
vegetable oils', 'hydrogenated vegetable oils' or 'shortening' is may
well contain trans fats. Commercial baked good such as cookies, cakes
and donuts; chips and other packaged fried foods; some fast food
chain products especially deep fried ones; snacks like microwaved
popcorn; vegetable shortening and many margarines are the most likely
products to have trans fat.
I have been waiting for this to happen
for at least a third of my life. My fasting blood sugar is over
normal. It is not just very close to the upper limit as it has been
for years, occasionally a point or two over but within normal when
repeated, it is actually, undeniably too high. The doctor said it was
not quite high enough to make a diagnosis of diabetes yet.
So what is type 2 diabetes, what I will
have soon if I don't watch out? Type
2 diabetes is not caused by destruction of the insulin making cells
in the pancreas as in type 1, but rather by the resistance to insulin
and the inability to produce enough extra insulin to overcome the
resistance. The high blood glucose and other changes damage many
organs especially the heart and blood vessels. So what I have is not
the autoimmune type1 like my father and uncle on the Barmby side, but
type 2 like my brother and my Wight grandfather.
involved in this disease is: metabolic syndrome (insulin resistance
and over production of insulin to overcome resistance) progresses to
type 2 diabetes not requiring insulin (high blood glucose because
insulin can no longer be produced in enough quantity to overcome
resistance) progresses to type 2 diabetes requiring insulin (the long
term over production of insulin has damaged to insulin producing
cells so that they cannot over produce anymore). I appear to be at
the point of passing from metabolic syndrome to mild type 2 diabetes.
So I have a few
early symptoms but not others.
- higher than normal fasting blood
sugar – yes but not all that high
- chronic fatigue, generalized
weakness and malaise – I definitely have fatigue and weakness
- Excessive urine production – not
- Excessive thirst and increased
fluid intake -not me
- Blurred vision (typically from
lens shape alterations, due to osmotic effects, e.g., high blood
glucose levels) - not me
- Unexplained weight loss - not me
(my weight has not changed at all for 4 years)
- Lethargy - yes
- Itching of external genitalia -
- Excessive bowel movements –
bowel problems probably not due to diabetes
- muscle wasting – maybe a little
- infections and slow healing sores
– scratches etc. take longer to heal for last year or so
- leg pain – not me (just the
Causes and risk
disease has a genetic aspect, it is also due to lifestyle. This can
be seen from the adoption of the Type 2 epidemiological pattern in
those who have moved to a different environment as compared to the
same genetic pool who have not. Immigrants to Western developed
countries, for instance, as compared to lower incidence countries of
especially abdominal fat - yes
-yes but under control with medication
- high blood
cholesterol and triglycerides – yes just high-ish
syndrome – I think so
- aging -yes
- high-fat diet
- less active
- some other
diseases, cancers - no
- drugs –
possibly my blood pressure medicine (beta-blockers and diuretics)
- smoking –
not for years
alcohol – not me
with type 2 diabetes - yes
has to be controlled to avoid these dangers.
- ulcers and
circulation problems in feet and legs
- eye damage
- HONK or
hyperosmotic non-ketotic coma
above is the conventional info and advice. In later months I will
look at some of the areas where there is more recent and detailed
- First is
exercise but it does not need to be excessive. A brisk 45 min walk a
day is sufficient. I might be able to work up to that.
- Second is
weight lose. Again it does not have to be excessive but losing
abdominal fat is the important thing.
- Changes in
diet especially lowering fat and refined sugar and carbohydrates. I
eat very little carbohydrates (although a few times a year I eat
some very sweet things). I eat some quite fat rich foods.
- Medication needed in some cases, even insulin in very severe cases .
What can I do with my diet?
Glycemic index and glycemic load are
measures of how quickly and how high certain foods affect blood sugar
compared to pure glucose. The index is based on a standard weight and
load is based on normal serving amounts. Eating low glycemic foods
limits the blood sugar rise after a meal and therefore the need for
So it seems a good idea to eat
primarily low glycemic load foods to postpone diabetes.
Unfortunately, I do this already for other reasons. Because of my
adult celiac condition, I long longer eat any bread, pasta or
couscous, if fact I eat nothing with any wheat or barley in it. That
cuts out a lot of high glycemic foods.
I also watch my weight so it does not
rise. So although I can tolerate rice, potatoes and corn, I do not
eat much of them. Harry has potato with his evening meal and I often
put a little slice on my plate. I cook rice about once a week for our
evening meal and have a serving (sometimes a large serving). We no
longer have polenta but I eat canned sweet corn probably every other
day. I sometimes have some cornflakes, maybe once a month. I eat very
little candy – a bit at Christmas, some when Ciara and Ryan are
here, and a piece of dark chocolate occasionally. I eat canned
beans/peas only about once a week when I put them in my chicken soup.
There is a small amount of sugar in my yogurts. The only high
glycemic fruit or vegetable I eat is a couple of bananas a day. That
is it for high and medium glycemic index foods. Otherwise I eat
fruits and vegetables, often raw, and proteins (meat, fish, cheese
and eggs). My snack when I'm peckish is peanuts, roasted, not salted.
I do not want to cut out anything completely from what seems a
healthy diet for me and so about all I can do with my diet is to eat
less of the banana and cut out rice and take the little milk I have
without the cornflakes. That does not seem a big change and so not
that much can be gained from this corner.
Over and above the foods that are not
glycemic, there may still be foods that are helpful in other ways
such as directly counteracting the resistance to insulin that is the
root of the disease. There are some foods that are particularly
-Virgin olive oil – Virgin olive oils
contain polyphenols as well as some particularly healthy fats found
in all olive oils. This polyphenols have been shown to be one of the
important components of the Mediterranean diet's healthiness.
Consumption of virgin olive oil
in conjunction with a Mediterranean diet can positively impact lipid
and DNA oxidation, insulin resistance, inflammation, carcinogenesis,
and tumor suppression and these effects are thought to involve
changes to the way genes are expressed.
wine and red grapes – The active ingredient is resvertrol which
actives sirtuins in various tissues and this activation is thought to
be anti-diabetic. There is also a theory that resvertrol is
-Antioxidants (Vit C, Vit E, selenium,
carotenoids found in fruits, vegetables, legumes and nuts) -
Antioxidants improve many metabolic syndrome symptoms including
insulin resistance. However, this is something of a two edged sword
because taking in too much antioxidant can interfere with energy
production, in particular the delivery of oxygen to the muscles. Many
of the compounds that antioxidants eliminate are active in increasing
the diameter of blood vessels and stimulating energy production. A
lot of people don't realize is that the antioxidant and pro-oxidant
balance is really delicate. (Some experts want the recommended
intakes of nitrate, nitrite and nitric oxide raised for good cardiac
health and these are some of the chemicals lost to the actions of
antioxidants – the N compounds are found in many vegetables and
– The caffeine in coffee can reduce the risk of type 2 diabetes and
is beneficial in limiting fatty liver and inflammatory cytokines from
D – Vitamin D deficiency is prevalent and is especially found in
aging people. The deficiency appears to be a risk factor for type 2
diabetes and vitamin D supplements are beneficial in treatment of
-Soy (the isoflavones, daidzein and
equol, specifically) – they activate a transcription factors and
signaling molecules that are important for glucose uptake and insulin
sensitivity, in a similar manner to anti-diabetic drugs.
fruit (the flavonoid, naringenin specifically) – effect in reducing
weight gain, insulin resistance and cartiovascular disease. It has an
-Low fat –
a high fat diet is believed to cause inflammation leading to insulin
resistance. (It is also believed to cause obesity but a high carb
diet is even worse for weight gain. The inflammation problem is
separate from the weight gain problem although they are often
So what is
there here that I can do? Not much is not in my current diet; I can
add soy and reduce the fat a little. That is it.
factor to consider is sleep apnea. It is hard to tell if I suffer
from this, both I think I do to a small extent. Both intermittent
hypoxia (sleep apnea) and continuous hypoxia (living at high
altitude) affect glucose tolerance but only intermittent reduces
insulin sensitivity. Obesity make people more prone to sleep apnea
so, again, I should lose weight.
Not all diseases are equal
(thanks to Mind Hacks blog) There is a
hierarchy of prestige in medicine. It's interesting that doctors who
specialise in working with people who have the least status in
society (children, the 'mad', the 'old') also have the least status
in medicine. The Norwegian researchers asked senior doctors, general
practitioners and medical students to rate diseases and came up with
the following list, which ranks diseases from the most prestigious at
the top, to the least prestigious at the bottom.
Myocardial infarction [heart
Pulmonary embolism [normally blood clot on the lung]
rupture ['torn cartilage']
Ulcerative colitis [inflammation of the
Duodenal ulcer [peptic
Sciatica ['trapped nerve']
[arthritis of the spine]
Femoral neck fracture
Inguinal hernia [abdominal wall
Apoplexy [internal organ bleeding]
Hepatocirrhosis [cirrhosis of the liver]
And then there is activity...
Sarcopenia is a condition of low
skeletal muscle mass and strength that occurs in older people and the
obese. It is associated with insulin resistance and elevated blood
glucose. Dieting is not enough to avoid type 2 diabetes; it is
important to be fit and avoid sarcopenia.
Exercise is important for avoiding type
2 diabetes, over and above its body fat reduction. Not that much is
required 150 minutes of walking a week or 60 minutes of more
strenuous activity will give beneficial changes in lowering insulin
resistance. More than this does not seem to have any extra advantage
other than weight loss (decreases hunger signals) and general fitness. One thing that is
important is that the exercise is regular.
It may also be the case that adrenaline
production during exercise can cause the uptake of blood glucose by
muscle without the action of insulin. I have read this but have not
yet found corroboration.
I have re-started a lunch time walk
which I used to do.
The amount of time spent sitting
(independent of the amount of activity and exercise) influences
triglycerides, high density lipoprotein, cholesterol, blood glucose,
blood pressure and leptin – all markers of obesity, cardiovascular
disease, metabolic syndrome and type 2 diabetes.
In seems that bone is not just a rigid
framework, the place where blood cells are formed and a reservoir of
calcium, potassium and fat. It is an active player in metabolism.
There is interplay between bone and blood sugar, based on signals
sent via insulin and a bone-derived hormone known as osteocalcin.
Bone is continually broken down by
osteoclasts and built up by osteoblasts. The density of bone is a
balance between the activity of these two cell types. Too much
re-absorption and too little creation gives osteoporosis.
Osteoblasts have insulin receptors and
when not stimulated by insulin decrease bone formation – insulin is
needed to maintain bones. But also, bone produces osteocalcin which
stimulates the pancreas to make more insulin and various cells to be
more sensitive to insulin. This appears to be a positive feedback
loop. It is more complicated because insulin stimulates osteoblasts
to produce inactive osteocalcin which sticks to the bone and cannot
circulate in the blood to stimulate the pancreas and other cells. It
cannot increase insulin or insulin sensitivity. A built up of this
inactive osteocalcin stimulates the osteoclasts to break down bone.
The action of osteoclasts create acid and this converts the
osteocalcin to become active and escape into the circulation.
Now that there are preventions, cures
and treatments for the majority of the diseases that killed our great
grandparents and their ancestors, we die of accumulated mishaps. Our
fears are cancer, the result of a series of uncorrected metabolic
damage, or heart attacks, the result of the wear and tear of life.
Now our greatest enemy is stress because stress makes us tear out
faster and repair our little damages less well.
It is becoming clear that it is not
just stress that is dangerous – there is good stress and bad
stress. The really damaging situation is to have stress consisting of
very high demands and very low control. This is the type of stress
There are some recent figures giving a
feel for how important stress is. “The list of ailments connected
to stress is staggeringly diverse and includes everything from the
common cold and lower-back pain to Alzheimer's disease, major
depressive disorder, and heart attack. Stress hollows out our bones
and atrophies our muscles. It triggers adult onset diabetes and is a
leading cause of male impotence. In fact, numerous studies of human
longevity in developed countries have found that "psychosocial"
factors such as stress are the single most important variable in
determining the length of a life.” and “The Whitehall study, an
exhaustive longitudinal survey launched in 1967 that has tracked some
28,000 British men and women working in central London. The
differences are dramatic. After tracking thousands of civil servants
for decades, Marmot was able to demonstrate that between the ages of
40 and 64, workers at the bottom of the hierarchy had a mortality
rate four times higher than that of people at the top. Even after
accounting for genetic risks and behaviors like smoking and binge
drinking, civil servants at the bottom of the pecking order still had
nearly double the mortality rate of those at the top. Promotion from
the lowest level in the British civil service reduced the probability
of heart disease by up to 13 percentage points. ”
When I was younger I thought that I was
just one of those people that was immune to stress. I was not someone
who got angry and smoldered; I was not a worrier either. As I got
older, my jobs tended to have more and more control. I was usually
lucky with my immediate bosses. When I retired I was very surprised
at the difference it made. The stress I had not thought was there was
noticeable in its absence. Over several months my health seemed to
improve. Now I really savour the lack of stress in my life. Or maybe
I am just savouring life. Here is the way our outlook changes as we
age. “In measuring immediate well-being — yesterday’s emotional
state — the researchers found that stress declines from age 22
onward, reaching its lowest point at 85. Worry stays fairly steady
until 50, then sharply drops off. Anger decreases steadily from 18
on, and sadness rises to a peak at 50, declines to 73, then rises
slightly again to 85. Enjoyment and happiness have similar curves:
they both decrease gradually until we hit 50, rise steadily for the
next 25 years, and then decline very slightly at the end, but they
never again reach the low point of our early 50s.”
A treatment for alzheimers will be
later rather than sooner
It seems that ideas are not working out
for finding treatments or cures for alzheimers. That is a shame but
it can be predicted to happen every so often. Years back researchers
thought they knew where the problem was – the amyloid plaques
caused the malfunction and death of neurons. Find a way to stop
plaques from forming or getting rid of them after they formed was the
answer. Many (probably most) drug companies started projects to
attack amyloid plaques and many other funders gave money to
researchers who had good ideas along this line.
Of course there were indications early
on that amyloid plaques might not be the only cause or even a cause
at all for the symptoms of alzheimers. Some people looked at tau
tangles and various metals. But this is always the case even if the
main work is on a successful track. Eventually others were looking at
blood vessels, energy metabolism, inflammation and calcium signals.
But the bulk of the money did not go on these other possibilities but
on the amyloid plaque hypothesis. Now it looks like the plaque thing
is going to fizzle and it is going to take time for it to run its
course so that the big money can go into other hopes.
First it appears that people who do not
have alzheimers or any similar condition, do still have amyloid plaques.
Second, the actual amount of mental degradation in alzheimers does
not seems to follow closely the actual amount of plaque. Third, the
free precursors of plaque seem to be somewhat toxic to neuron cells
whereas they lose their toxic nature when bound in plaques – ie
plaques may be a sign of some sort of protection mechanism. Fourth,
the genetic link between amyloid processing genes and alzheimers that
was found for the rare early onset alzheimers does not seem to hold
for the common age related alzheimers. Finally, so far the drugs and
vaccines that have had trials for ridding the body of amyloid from
plaques have either shown no benefits or have made patients worst.
Many more trials are in the pipeline but hope is fading for them.
Occasionally you can still read quotes
from scientists and more often from science journalists that just
state boldly that amyloid plaques are the cause of alzheimers without
any hedging. I guess that if you have enough years of your life
invested in the idea, it is hard to question it.
medicine is intended to predict the risk of disease or response to a
drug based on a person's genetic makeup. Sounds like a great idea. It
is being hyped, but is it possible?
genes work is greatly influenced by their environment. Even in simple
organisms, like yeast, the effects of gene combinations are not
predictable from one group of food sources to another. It is pretty
hard to get a system that is simpler than that – combinations of a
handful of genes and a handful of sugars, only a few hundred ways to
put them together.
even describe human environments in scientific usable ways. Even when
we might understand all the genetic variations in people, it will
still be a long time to understand our environments and the
interactions between them and the genes.
stuck with statistical medicine for some time before we have
(Of course a certain amount of understanding of the patient's genetics may help to make the statistics were accurate.)
Why is a
purely genetic approach to diagnosis being hyped as a near-future
possibility? This is one of my pet peeves – we should forget about
'nature vs nurture'; there is almost nothing that is controlled by
pure genetics or pure environment. Our ignorance of the interaction
between the two is enormous, still that is where the better medicine
will be found. I feel like screaming out loud every time I read
'nature vs nurture'. It should be 'and'. I do not understand why
people keep trying to find evidence that one or the other is the more
important. How can a reasonable person think that either is
environment cannot yet by quantified, the genetic map is not yet
understood and the interaction is a mystery, but still some people
want to fight about whether genes or environment wins some sort of