Imagine a medicine which protects you against cardiovascular
disease, cancers, diabetes, depression and dementia. A medicine which works
best when taken regularly and long before any symptoms of any of those diseases
appear. A medicine which is cheaper than any supplement or aspirin. Would you
take it?
Our best bet for healthy aging is to escape the flawed health care system. It makes disease treatment more profitable than prevention. It neglects aging as a treatable cause of diseases. And it denies access to personalized lifestyle medicine. This blog is about how you can overcome these limitations. It is about challenging half-truths and outdated ideas. It is focused on evidence-based, personalized lifestyle medicine for lifelong health. Delivered by a feisty public health scientist.
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Monday, April 30, 2012
Friday, April 27, 2012
Your shortcut to longevity.
If you don't die from an accident, a serious infection or a
cancer, you'll live as long as your arteries let you. And how long they let you
is all in your hands. I know this sounds over-simplified, but it's biomedical
knowledge in a nutshell. Lets look at what happens in and to your arteries and
what that means for keeping them in mint condition.
Wednesday, April 25, 2012
It's not your genes, stupid.
Imagine traveling back in time and meeting your caveman ancestor of 10,000 years ago. Imagine telling him about what life is like today: that, with the tap of a finger you turn darkness into light, a cold room into a warm one and a tube in the wall of your cave into a spring of hot and cold water. You tell him...
Monday, April 23, 2012
To hell with exercise
Who says that exercise is medicine? For one, the American College of Sports Medicine (ACSM) of which I'm a professional member. Then, how can I say it isn't?
Let's look first at the conventional view of the benefits of
exercise. There is a large and increasing amount of evidence which clearly
tells us that exercise prevents today's number 1 killer: cardiovascular
disease. That is, heart attack, stroke and peripheral vascular disease. Mind
you, what is common knowledge today emerged only some 50 years ago when Morris
and colleagues discovered that UK bus conductors, the guys climbing up and down
the double-decker London buses, had better fitness and fewer heart attacks than
their all-day-seated driver colleagues [1].
In the years since then our knowledge about the effects of
physical activity on cardiovascular, metabolic and mental health has virtually
exploded. From this evidence the U.S. Dept. of Health and Human Services (HHS) concluded
in 2008 that the most active people of the population have a 35% reduced risk
of dying from cardiovascular disease compared to the least active people [2]. The WHO lists insufficient physical activity (PA) as the 4th
leading cause of death world wide after high blood pressure, tobacco use and
high blood glucose. What's wrong with this picture? High blood pressure and
high blood glucose are known consequences of a sedentary lifestyle. So is
obesity, which ranks 5th place on the WHO killer list. Which is why physical
inactivity deserves top spot on that list.
What most people don't know is the way lack of physical activity
causes all those diseases, from insulin resistance and diabetes to arterial
dysfunction and atherosclerosis, and from there to heart attack, stroke, kidney
failure. The mechanisms are extremely complex, and, while we have untangled
quite some of them, there are probably a lot more to discover. I'll try to make
this the subject of one of the next blog posts.
Now you are probably asking yourself, how the hell, with all
this evidence, will I ever be able to make my point that physical activity is
not a medicine. Ok, here it comes: it's a matter of viewpoint. The one I'm
taking is the one of evolutionary biology. Let me play its advocate and present
as evidence a couple of insights.
First, our human ancestors, who had roamed this Earth as
hunter/gatherers for the most part of human existence, had, by necessity, a
much more physically active lifestyle. A lifestyle which required at least 1.7
to 2 times the normal resting energy expenditure [3]. [To get an idea about
resting energy expenditure and physical activity levels and how they are
calculated, simply follow the links to the videos.] Those ancestors' genes are
what we have inherited. And these genes are exposed to a lifestyle which is
vastly different from the ones under which these genes evolved. Specifically
with a view to physical activity, which brings me to evidence no 2:
What we typically observe today are physical activity levels
with factors of somewhere between 1.2 and 1.4 of our resting energy
expenditure. That's true for most people.
Even if you were to follow the ACSM's recommendation of 30
minutes of moderate to vigorous exercise on at least 5 days per week, would you
NOT reach the level of 1.7 if you are working in a typical office job or doing
house work. Which means, the physical activity levels which we recommend today,
do not add a behavioral type of medicine into our lives, they merely reduce the
extent of a "poisonous" behavior called sedentism. It's like cutting
down from 2 packs of cigarettes per day to 1 pack. Would you call this a
"medicine"? Would the ACSM call that a medicine? With respect to
exercise they do.
So, OK, if you had been attracted to this post in the hope
of finding some excuse for not doing exercise, or some argument to get those
exercise evangelists, like myself, off your back, I'm sorry to have
disappointed you. No, actually, I'm not sorry. And neither will you be, if you get your
physical activity level above those 1.7. Then you may just start calling
exercise a medicine. Until then, chances are you will still go to hell with exercise, because you get too little of it. Certainly too little to stay out of that hell of heart disease, stroke, diabetes and many cancers.
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MORRIS JN, & RAFFLE PA (1954). Coronary heart disease in transport workers; a progress report. British journal of industrial medicine, 11 (4), 260-4 PMID: 13208943
Eaton, S., & Eaton, S. (2003). An evolutionary perspective on human physical activity: implications for health Comparative Biochemistry and Physiology - Part A: Molecular & Integrative Physiology, 136 (1), 153-159 DOI: 10.1016/S1095-6433(03)00208-3
Friday, April 20, 2012
Screw Your Health?!
So, what's your excuse for not exercising enough, for
smoking, for not watching your diet, for getting fatter every year, and
therefore having high blood pressure, and too much glucose and cholesterol in
your blood?
Thursday, April 19, 2012
Chronisch gesund geht doch!
In meinem vorangegangenen Beitrag habe ich erläutert, wie unser Gesundheitswesen dem Ziel der chronischen Gesundheit im Wege steht. Wie dieses Ziel erreichbar ist, ist Gegenstand meines heutigen Beitrags.
Gesundheit als shareholder value.
Anfang diesen Jahres drohte die Ratingagentur Standard & Poor's den G20
Nationen mit einer Herabstufung ihrer Ratings beginnend in 2015. Der Grund: Die
bestehenden Gesundheits- und Rentensysteme werden unter der Krankheitskostenlast
einer zunehmend älter, kränker und dementer werdenden Bevölkerung
zusammenbrechen. Und damit das Wirtschaftswachstum ausbremsen.
Warum ist dieser Schuss vor den Bug so wichtig? Weil hier ausgesprochen
wird, was schon lange hätte erkannt werden sollen: Gesundheit ist nicht nur das
vielzitierte hohe Gut. Sie ist ein Wirtschaftsgut.
Ihre Gesundheit macht Sie produktiver für Ihren Arbeitgeber und profitabler
für Ihre Krankenkasse und Ihren Lebensversicherer. Sobald Ihre Gesundheit im Universum
des Shareholder Value auftaucht, haben Ihr Arbeitgeber, Ihre Kasse und Ihre
Lebensversicherung auch finanzielle Anreize, in Ihre Gesundheit zu investieren.
Und einen Anreiz, den Return-on-Investment mit Ihnen zu teilen. Im Rahmen einer
Gesundheitsdividende, die Sie für Ihre Gesundheitsbemühungen belohnt. Das
Schlüsselwort heißt Anreize. Fehlende Anreize sind der Grund für das Versagen
der Präventionsbemühungen unseres Gesundheitswesens.
Egal ob Geld oder Anerkennung oder was auch immer Ihren Nachbarn grün vor
Neid werden lässt, die treibende Kraft hinter allem menschlichen Handeln sind
Anreize. Sie sind als Triebfeder unseres Handelns in unsere Hirne programmiert.
In der programmiersprache des hyperbolic discounting. Wenn uns dieses Phänomen etwas
gelehrt hat, dann ist es die Notwendigkeit von Anreizen, mit denen wir jene
ausstechen können, die uns zu ungesundem Verhalten verführen.
Was hält unsere Firmen davon zurück, die Gesundheit ihrer
Beschäftigten massiv mit Anreizen
zu fördern? Sicherlich nicht die Geringschätzung ihrer Beschäftigten. Und
selten die Unberechenbarkeit des Return on Prevention. Meistens liegt es am
Fehlen eines Werkzeugs, das es ermöglicht, Belohnung an jene zu verteilen, die
es verdienen, und jenen vorzuenthalten, die nichts für ihre Gesundheit tun. Mit
Yoga- und Betriebsportgruppen gelingt das sicherlich nicht. Dass solch ein
Werkzeug im Rahmen betrieblicher Gesundheitsförderung funktioniert stellen wir
gerade unter Beweis. Wir haben dieses Werkzeug entwickelt um damit auch die
zweite und dritte Strategie zu realisieren.
Den eigenen Kopf überlisten
Wenn's ums Esesn geht lässt sich der Affe in uns kaum von dem kontrollieren,
was uns zum Menschen macht: Vernunft und freier Wille. Aber egal ob Mensch oder
Affe, Mutter Natur hat uns die Gabe des impliziten Lernens gegeben. Mit ihr
lernen wir komplexe Aufgaben zu meistern ohne erklären zu können, wie wir das schaffen.
Denken Sie ans Schwimmen oder ans Radfahren. Dies sind Beispiele für einen 6.
Sinn, mit dem wir unser Verhalten präzise so steuern, dass wir weder ertrinken
noch vom Rad stürzen. Warum nicht auch unser Essverhalten? Mit einem 6. Sinn für die tägliche
Kalorienbilanz schaffen Sie zwar nicht die Lust auf das Tiramisu aus der Welt,
aber er hilft Ihnen zu erkennen, welche Maßnahmen notwendig sind, um Ihre Kalorienbilanz
heute auf dem Kurs zu halten, mit dem Sie planmäßig Ihr Gewichtsziel erreichen.
Dass es funktioniert haben wir in unserem Labor getestet. Die Idee dazu kam uns
im Rahmen einer klinischen Studie, in der wir testeten, wie wir jenen Menschen
zur chronischen Gesundheit verhelfen können, die am stärksten gefährdet sind:
Übergewichtigen und Adipösen. Unser Probanden, die diesen 6. Sinn entwickelten,
nahmen ab und hallten ihr Gewicht noch heute.
Nun stellen Sie sich wahrscheinlich die Frage: Selbst wenn mein Arbeitgeber
mir die notwendigen Anreize gibt, wie kann ich sicher sein, dass mein geändertes
Bewegungs- und Ernährungsverhalten mir auch tatsächlich die chronische
Gesundheit beschert? Womit wir beim letzten Punkt angekommen sind:
Die Biomedizin weiß was wirkt
Die Biomedizin kennt keine wirksamere Intervention zur Verhütung von
Herzinfarkt, Schlaganfall und Diabetes als zielgerichtete Bewegung und
Ernährung. Mit dieser Strategie reduzierten die Probanden des Diabetes Prevention
Program das Risiko, Diabetes zu entwickeln um rund 60%. Jene Probanden die
statt einer Lebensstiländerung das Medikament Metformin einnahmen, schafften
nur halb so viel, 30% Risikoreduzierung.
Dass Bewegung das Risiko an chronischen Krankheiten zu sterben um 40%
reduzieren kann, ist aus großen Studien bekannt. Damit ist Bewegung in
ausreichender Intensität, Dauer und Häufigkeit die wirksamste Strategie zur
Verhütung dieser Erkrankungen. Auch
vieler Krebserkrankungen, darunter Darmkrebs, Prostatakrebs und Brustkrebs. Unser Gesundheitssystem aber
verschleudert das Potenzial dieser Strategie, denn es ist auf die Behandlung
von Krankheit ausgerichtet, nicht auf den Erhalt der Gesundheit. Solange keine
Risikofaktoren messbar sind, bleiben wir aber unter dem präventiven Radar
dieses Systems. So lange bis es zu spät ist. Denn wer als Mann mit 45 Jahren
noch frei von Risikofaktoren ist, hat eine 97%ige Chance seinen 80 Geburtstag
bei guter Gesundheit zu feiern. Liegen bereits 2 Risikofaktoren vor, wie
beispielsweise Bluthochdruck und erhöhtes Cholesterin, dann schrumpft diese
Chance auf 50%. Und selbst wenn Sie zu jener glücklichen Hälfte zählen, die die
80 Kerzen auf dem Kuchen ausblasen darf, werden Sie genau das wahrscheinlich
nicht mehr schaffen, denn eine der chronischen Krankheiten wird Ihnen die Kraft
dazu genommen haben.
Die gute Nachricht: mit den einfachen Gesundheitsverhalten - nicht rauchen,
ausreichende Bewegung und kein Übergewicht - können Sie heute schon bestimmen,
wie Ihre 80. Geburtstagsparty ablaufen wird.
Die schlechte Nachricht: Das alles sind keine neuen Erkenntnisse. Den
Kassen sind sie genau so bekannt wie den Wissenschaftlern, die sie erarbeiten.
Dass Präventionsbemühungen trotzdem nicht von den Kassen finanziert werden, hat
erstaunlicherweise nichts mit Geiz oder Unvernunft zu tun, sondern mit dem
Paragraphen 20 des fünften Sozialgesetzbuchs. Dort schreibt unser Gesetzgeber
den Kassen eine Ausgabengrenze für Prävention vor: € 2,84 pro Versichertem pro
Jahr. Offensichtlich sind die Bekenntnisse unserer Gesundheitsminister zur
Prävention nichts anderes als Lippenbekenntnisse.
Es
sind also nicht Defizite in Wissen oder Fortschritt, die uns das Zeitalter der
chronischen Gesundheit und Langlebigkeit vorenthalten. Es ist das Versagen
unseres Gesundheitssystems, das Wissen einzusetzen und damit die Gesundheit
endlich als das zu behandeln was sie ist, ein Wirtschaftsfaktor. Ist das nun
wirklich eine so radikale Änderung der Strategie unseres
Gesundheitswesens?
Wednesday, April 18, 2012
Am I shittin' you? Learn to be a skeptic!
Learn to be a skeptic!
Why you cannot believe what you read about medical studies.
In my last blog post I promised to tell you why you shouldn't
trust any study results, particularly when you didn't read the study yourself.
It has to do with the methods of biomedical research. To make my point, I'll
take the gold standard research method, the double blinded randomized
controlled trial, or RCT.
Let's say we want to test a drug, which is supposed
to lower blood pressure in those who suffer from hypertension. The researchers
have decided to enroll, say, 100 "subjects". That's what we typically
call the people who are kind enough to play guinea pig in our studies.
The researchers will first do a
randomization of subjects into one of two groups (very often it is more than
one group, but to keep it simple we will assume just two groups). What we mean
with randomization is that we randomly assign each subject to one of the two
groups. One group - the intervention group - will receive the drug, the other
group - the control group - won't. What they get instead is a
sugar pill, a placebo.
With the randomization we want to make sure that, at the
start, or baseline, both groups are indistinguishable from each other with
respect to their average vital parameters. For example, if we were to calculate
the mean age, blood pressure and any other variable for each group, these mean
values would be not different between groups. That's important, because we want
to isolate the effect of the drug. We don't want to worry at the end whether
the effect, or lack thereof, was maybe due to some significant difference
between the groups at baseline.
Once the randomization is done, we organize the
trial in such a way that neither the "subjects" nor their physicians
and nurses know whether they get the placebo or the active drug. Both sides are
blind to what they get and give, which is why this set-up is called
double-blinded. That's an important feature, because a researcher often goes
into a study with a certain expectation of its outcome. Either that outcome
supports his hypothesis, or it doesn't. To eliminate the risk of, more or less
subconsciously, influencing the study towards a desired outcome,
double-blinding is very effective tool.
Fast forward to the end of our trial. We have now
all the data in hand to compare the two groups. After unblinding, the
researchers will compare the two groups with each other. In our example, they
will compare the average, or mean, of the blood pressure values of all the
individuals for each group. If the intervention group's mean value is lower
than that of the control group, then it is plausible to reject the
null-hypothesis, that is to REJECT the idea that the drug is NOT as ineffective
as the placebo (we are, of course, assuming here that the sugar pill didn't
lower the blood pressure of the control group). There are statistical tools to determine whether the difference between the groups may just be a chance event, or whether chance is a very unlikely explanation. We can never rule out chance completely. Now, when we are confident that it is the drug and not pure chance, which has lowered the mean blood pressure in the intervention group, we write our paper to present it in one of the medical journals.
If the subject is a little more sexy, than just lowering blood pressure, there will sure be some journalists who pick it up and report to their readers that, say, eating chocolate makes you slimmer. I'm not kidding. This headline very conveniently went through the media shortly before Easter this year [1]. Good for Hershey who are running it of course on their webpage. And in the media it reads like it did in the Irish Times: "Good news for chocoholics this Easter. Medical Matters: No need for guilt over all those Easter eggs."
I'm not going to comment on the media geniuses, because it's their job to put an angle on every story, so that YOU find it interesting and
read their stuff. But since I'm sure you'll follow these links, just let me
warn you: the chocolate study was an observational study, not an RCT. And one
thing we MUST NOT do with the results of observational studies is to confuse
association with causation. Only when we conduct an RCT, where the intervention
group eats chocolate and the control group doesn't, might we be able to
determine whether there is a causal link. And for obvious reasons we can't
blind the subjects, to whether they eat chocolate or not. But I'm digressing.
Back to our blood pressure study. When we compare the group
averages, everything looks very convincing. And sure enough, as researchers we
are happy with the results, and we are perfectly correct, when we conclude,
that this medicine does its job.
But will it do it for you? When you are
hypertensive? You might be wrong if you say "Yes". And you will be
wrong more often than we, as researchers, or your doctors care to admit. For
one simple reason: The variability of effect within the group. You give 50
people the same drug, and I bet with you, and I'm not the betting type, that
you'll have 50 different results.
The mean value of the entire group glosses
over these inter-individual differences. Let me give you an example from a study
performed on 35 overweight men, who were studied in a supervised and carefully
calculated 12-weeks exercise program, with the intention of reducing body
weight. The mean weight loss was 3.7 kg. That was almost exactly the amount of
weight loss which the researchers had expected from the additional energy
expenditure of the exercise program. But when they looked at each individual, it
became clear that the group mean doesn't tell you anything about how YOU would
fare in that program.
First of all, the standard deviation was 3.6 kg. Now, a
standard deviation of 3.6 kg simply tells you that approximately two thirds of
the participants experienced a weight loss anywhere between 3,7 kg (the mean) minus 3.6 kg
and 3.7kg + 3.6 kg, that is between 0.1 kg and 7.3 kg! That's a lot of kilos. And what about the
remaining one third of those participants? They are even further from these
values. In this case the greatest loser went down by 14 kg, and the biggest
"winner" gained almost 2 kg. A spread of 16 kilos!
Here is the graph which shows you the change on body weight
and fat for each individual participant. Which one would you be?
This effect is what you do not see when you don't read the
studies. And in most studies, it isn't made obvious either.
Which is why, you shouldn't
be surprised to learn that most major drugs are effective only in 25-60% of their
users [2]. The same goes for weight
loss drugs and interventions, for almost everything we study in biomedicine.
That's
not a problem for us in public health. Because a drug, which works in 60% of the
patients, helps us reduce the burden of disease in our population. Public
health is not interested whether you are one of the 60% or not. But you are. And
that's why I believe not only medicine, but also prevention must be individualized.
Which is why the GPS to chronic health, which I currently
develop, is all about helping you find your individual path to your health
objectives.
Why not have a look at it, and maybe even try it out?
References
Tuesday, April 17, 2012
Die Sucht aufs Essen. Warum wir dick werden obwohl wir es nicht wollen.
Unser Essverhalten wird weniger vom freien Willen und der Vernunft gesteuert, als vielmehr von autonomen Mechanismen. Den Verhaltensforschern sind sie bekannt. Den Akteuren unseres Gesundheitswesens sind sie ein Dorn im Auge. Ein Dorn, der sie mit einer selektiven Blindheit geschlagen hat für...
Die Sucht aufs Essen
Neurohormonale Mechanismen
treiben den Drogensüchtigen zu seiner Droge, obwohl er die Konsequenzen seines
Verhaltens kennt und fürchtet. Den Verhaltensbiologen sind diese Mechanismen
seit einigen Jahren bekannt. Und auch dass Zucker dieselben Hirnzentren und
Mechanismen aktiviert. Evolutionsbiologisch wichtige Mechanismen, wie wir heute
wissen. Denn die Lust auf Süßes trieb unsere Urahnen zu der einzigen Nahrung,
die diese Lust befriedigte: Obst und Früchte. Diese Lust war aus zwei Gründen
wichtig: erstens sind unsere Speicher für Kohlehydrate, anders als die fürs
Fett, sehr klein und innerhalb von spätestens 48 Stunden aufgezehrt. Zweitens
liefern Obst und Früchte lebenswichtige Mikronährstoffe. Ganz im Gegensatz zu
jenen Colas, Kuchen und Keksen, mit denen wir die Lust auf Süßes heute
befriedigen. Für diese Lust sollten wir uns also nicht deshalb schämen, weil
wir sie erst mit der Erforschung eines moralisch verpönten Verhaltens, der
Drogensucht, entschlüsselt haben. Das erklärt, warum die
Nahrungsmittelindustrie Zucker in allen möglichen Nahrungsmitteln versteckt, in
denen wir ihn nicht vermuten. So wie die Zigarettenindustrie ihre Tabake mit zusätzlichem Nikotin
anreichert, einem der stärksten Suchtmittel überhaupt. Die Konsequenz dieser
Sucht auf's Essen ist das Übergewicht. Womit wir beim zweiten Grund für das
Scheitern des Abnehmens sind:
Entgleiste Hormone
Wer lange genug zu viel isst und
sich zuwenig bewegt, verwandelt nicht nur seine Figur sondern auch seinen
Organismus. Gemeint ist damit jene komplexe neurohormonale Vernetzung von
Verdauungsapparat, Fettgewebe, Muskelzellen und jenen Hirnzentren, die Appetit,
Sättigung und den Drang auf Bewegung regeln. Wer nach einem Essen, das eine
vierköpfige Familie in Bangladesh ernährt hätte, der Lust auf ein Tiramisu
nicht widerstehen kann, hat das auch diesem neurohormonalen Netzwerk zu
verdanken. Es ist resistent geworden gegen Sättigungssignale. Wenig hilfreich
ist auch, dass der Anblick des Tiramisu einen Verhaltensreflex auslöst, den wir
von Boris Becker in der Besenkammer kennen. Erst mal vernaschen, bereuen kommt
später. Verhaltenswissenschaftler nennen dieses Phänomen...
Hyperbolic discounting
Discounting heißt Abzinsung. Was
der Verhaltensforscher darunter versteht, ist die Art, wie unser Gehirn intuitiv
den Gegenwartswert eines erwarteten zukünftigen Nutzens ermittelt. Vor die Wahl
gestellt, entweder 120 Euro in 6 Monaten geschenkt zu bekommen oder 100 Euro in
5 Monaten, entscheiden sich die meisten Menschen für die 120 Euro. Was aber,
wenn ich Ihnen 100 Euro jetzt bar auf die Hand biete oder 120 Euro in einem Monat?
Die meisten Probanden ziehen die sofort verfügbaren 100 Euro vor. In beiden
Fällen ist die Differenz die Gleiche, nur Sie bewerten sie intuitiv anders. Dieser
Effekt ist mit dem Wörtchen "hyperbolisch" beschrieben, einer
mathematischen Formel die sich von der exponentiellen Form der Abzinsung
unterscheidet, auf der wir unser Banken- und Wirtschaftssystem aufgebaut haben.
Dank der hyperbolischen Abzinsung
greifen Sie morgen doch wieder zum Tiramisu, obwohl Sie heute Stein und Bein
schwören, dass Ihnen der Gesundheitsgewinn in der ferneren Zukunft wirklich
mehr wert sei als der Lustgewinn nach dem Mittagessen morgen. Und genauso
funktioniert nicht nur das menschliche Gehirn sondern auch das von Tauben,
Mäusen und Affen. Das zeigt, im Laufe der Evolution muss sich die hyperbolische
Abzinsung als wirksames Werkzeug fürs Überleben bewährt haben. Andernfalls
hätte Mutter Natur es nicht über Millionen Jahre in die Hirne ihrer Spezies
programmiert. Heute müssen wir mit diesem Erbe in einer Umwelt zurechtkommen,
deren Gestaltung wir Mutter Natur aus der Hand genommen haben.
Dem Aberglauben an die Vernunft
und den freien Willen als Treiber unseres Ess- und Bewegungsverhaltens hätten diese
Erkenntnisse schon seit mehr als 10 Jahren den Wind aus den Segeln nehmen
müssen. Haben sie aber nicht. Wohl weil es einfacher ist, den Dicken und
chronisch Kranken die Schuld für ihren Zustand zu geben, als sich zu fragen,
wie das Produktions- und Werbeverhalten einer Nahrungsmittelindustrie, von
Nestle bis zu MacDonalds, zu reglementieren sei.
Und wie kann ich nun behaupten, dass das Zeitalter
der chronischen Gesundheit greifbar ist?
Aus
drei Gründen: weil sich die Börsen für das Thema zu interessieren beginnen,
weil wir unser Hirn überlisten können, und weil wir die notwendigen Werkzeuge
aus den Gesundheitswissenschaften haben. Dazu mehr im nächsten Beitrag. Und falls es Ihnen bis dahin langweilig werden sollte, können Sie ja schon mal einen Blick auf unser Navi zur chronischen Gesundheit werfen.
Monday, April 16, 2012
Chronisch gesund geht. Aber nicht mit unserem Gesundheitssystem.
So versagt unser Gesundheitswesen
Das Faszinierende an unserem
Gesundheitssystem ist, dass es 8 von 10 Deutschen an chronischen Krankheiten
leiden und sterben lässt, obwohl wir genau wissen, wie wir diese Krankheiten
verhüten können. Also warum tun wir's nicht?
Als Gesundheitswissenschaftler
arbeite ich seit 15 Jahren an der Beantwortung dieser Frage. Viele meiner
Kollegen warnen mit immer dunkler werdenden Zukunftsvisionen vor einem Tsunami aus
Behandlungs- und Pflegekosten für unsere zunehmend älter, kränker und dementer
werdende Bevölkerung.
Dabei könnten wir das Zeitalter
der chronischen Gesundheit bereits jetzt einläuten. Ein Zeitalter in dem Herzinfarkt, Schlaganfall und viele
Krebsarten ihre Bedeutung in der Sterbestatistik verloren haben werden. So wie
die ansteckenden Krankheiten nach der Einführung der Hygiene. Aber so, wie wir Prävention bislang
machen, funktioniert sie nicht. Die Entscheidungsträger unseres
Gesundheitssystems kämen zum gleichen Schluss, wären sie nicht mit einer
selektiven Blindheit gegenüber unbequemen Fakten geschlagen.
Das Versagen der Prävention
Die Akteure unseres
Gesundheitswesens verweisen gerne auf große staatlich finanzierte Studien, wie
das US amerikanische Diabetes Prevention Program und die Look AHEAD Studie, die
zeigen, wie wirksam simple Lebensstiländerungen für die Prävention der
chronischen Erkrankungen sind. Worüber sie nicht gerne reden ist, wie flüchtig
diese Erfolge sind. Für die meisten Teilnehmer sind anfängliche
Gewichtsverluste spätestens nach 3 bis 4 Jahren wieder "aufgezehrt",
und Risikofaktoren sind wieder auf dem Stand vor Studieneintritt.
Wie kann man behaupten Prävention
funktioniert, wenn das Übergewicht zum Rauchen des 21. Jahrhunderts geworden ist?
Wenn für jeden US Bürger, der 2011 das Rauchen aufgegeben hat, ein anderer
adipös (BMI > 30) wurde? Wenn zum ersten Mal in der Menschheitsgeschichte es
mehr übergewichtige als unterernährte Menschen auf dieser Welt gibt? Deren
Lebensstil aus zu viel Essen und zu wenig Bewegung ist der größte Risikofaktor
für die vermeidbaren kardiometabolen Erkrankungen und ihre klinischen
Endpunkte: Diabetes, Herzinfarkt, Schlaganfall, Herzversagen.
Wenn also die Änderung des
Gesundheitsverhaltens Krankheit verhindert, was verhindert dann die Änderung
des Gesundheitsverhaltens?
Der Aberglaube an ein willensgesteuertes Gesundheitsverhalten.
Wir alle wissen, dass Übergewicht
und Bewegungsarmut ungesund sind. Trotzdem sind zwei von drei Deutschen
übergewichtig und weniger als jeder fünfte bewegt sich ausreichend. Die
logische Schlussfolgerung: Wenn Sie einen Lebensstil wählen, von dem Sie
wissen, dass er Ihnen Krankheit und vorzeitigen Tod bringt, dann treffen Sie
diese Wahl entweder mit Ihrem freien Willen, oder es ist nicht Ihr freier Wille,
der Ihr Gesundheitsverhalten treibt.
Offensichtlich ist letzteres der
Fall. Wie sonst können wir erklären, dass übergewichtige Kinder ihr Ess- und
Bewegungsverhalten beibehalten, obwohl sie ihren Leidensdruck aus Übergewicht
und Stigmatisierung als genauso schwer empfinden wie ihre krebskranken Altersgenossen den einer Chemotherapie. Wie
sonst können wir erklären, dass adipöse Erwachsene nicht abspecken, obwohl ihre
Aussichten eine akademische Ausbildung, einen Job und einen Geschlechtspartner
zu finden deutlich schlechter sind, als die ihrer normalgewichtigen
Altersgenossen? Wie sonst können wir erklären, dass der Prozentsatz der
Adipösen unter den US Bürgern in den letzten 20 Jahren um 60% gestiegen ist, während
sie im gleichen Zeitraum ihre Ausgaben für Abnehmprodukte auf jährlich 60
Milliarden Dollar verdoppelt haben? Sie alle WOLLEN abnehmen, aber sie schaffen
es nicht. Aus drei Gründen.
Über die Sucht aufs Essen, über entgleiste Hormone und über hyperbolische Verzinsung in unseren Hirnen geht's in meinem nächsten Blogbeitrag. Und bis dahin, schauen Sie sich doch mal an, wie Sie bereits jetzt auf den Weg zur chronischen Gesundheit und guten Figur kommen.
Nano-encapsulated supplements. Ballyhoo or miracle drug?
When humble supplements meet ultra cool nano-technology.
I'm going to continue where I left off in my previous post: With the
question:
Does nano-encapsulation improve the effect of multi-vitamin
multi-mineral supplements?
When I was confronted with this question my immediate
reaction was: What is wrong with old-fashioned natural delivery of vitamins,
from eating fruit, and vegetables, and, yeah, eggs and meat and drinking milk,
all of which are the natural carriers of vitamins and more? Is this "nano-whatever"
just a cool gimmick of an industry pushing a market, which "suffers"
from only moderate growth? I admit it, I have a bias. A bias for evidence.
And as a health scientist I also have
to admit that nano-encapsulation appeared, until now, only on the very fringes
of the radar screen with which I observe the thousands of studies published
each year on the subject of preventable, lifestyle-dependent chronic diseases.
Literally thousands! Now go to PubMed, where the US National Library of
Medicine and the National Institute of Health collect and archive all of those millions
of studies and papers written on anything related to biomedicine and search for
the combination of the terms "nano-encapsulation" and
"vitamin" and you will find the stupendous number of ...
10 papers. None of them related to the oral administration
of vitamins. That settled my initial fear, that my radar might have had a blind
spot. The drawback was, I can't argue the case, for or against the usefulness
of nano-encapsulation, based on published evidence. That leaves me no choice
than to do what we scientists are supposed to do: to come up with testable
hypotheses on subjects of which we have no, or not enough, knowledge. Which is
why my answer to Björn's question will admittedly, be a highly subjective one.
But then, there is no clear-cut answer anywhere else to get. Beware of the
types who claim to have that answer!
Now let's get the technicalities out of the way first. What
does nanoencapsulation mean? It simply means to coat one substance with another
at sizes ranging from 1 to 1000 nm. The purpose of doing that is to
·
deliver a drug to a specific tissue or site in
an organism, where the drug is then released
·
slow down or time the release of a drug. Which
is a good way of delivering Insulin via a nasal spray, a very new technique,
which has shown some promise in reducing food intake in overweight women.
·
adding certain micro-nutrients, such as omega-3
fatty acids, to foods without altering the foods' textures or tastes, and to
prevent degradation of the otherwise volatile micro-nutrient
·
increase the shelf-life of vitamins
·
increase the bioavailability of anti-oxidants
and to prevent unwanted reactions with other food items.
There are lots of other uses in the food and cosmetics
industry, but they do not concern us here.
What we want to know is, whether a nano-encapsulated vitamin
supplement does its job any different from, and possibly better than, a
supplement that is not so encapsulated.
Now when you take in vitamins, with your food or with
supplements, these vitamins need to travel from the mouth through your
esophagus and stomach to the small intestine where they will be absorbed
through the intestine's membrane. Water-soluble vitamins are typically
transported via some sort of a carrier, with the exception of vitamin B12, for
which specific receptors do that job. Fat-soluble vitamins require the presence
of the same enzymes which fat itself requires for being absorbed. All this
happens in the small intestine, the one into which the stomach empties its
content. These processes are complex but well researched and known in great
detail. Now, just for laughs, let's look at what the geniuses at one of the
nano-encapsulation supplement producers have to say about the point where
nano-encapsulated vitamins meet the small intestine.
And I quote from here (http://livethesource.com/index.php/products/dailymultivitamin):
"livethesource® nanotechnology creates a particle size
small enough to be efficiently absorbed, yet not so small as to be
counterproductively absorbed by the body. We use all natural plant lipids as
the basis of our nano encapsulation material. The importance of this cannot be
overstated. The food grade material not only is absorbed and recognized as a
safe substance, but also delivers its payload in a quick, safe and efficient
manner."
"small enough to be efficiently absorbed" - as
opposed to what? In the intestine water-soluble vitamins are transported
molecule by molecule across the intestinal barrier and fat soluble vitamins are
integrated into the micelles, which are small enough to pass through this
barrier. That's what happens to the vitamins in your food. No nanoencapsulation
required here. I also fail to understand what could possibly be a
counterproductive absorption. Either vitamins are absorbed, or they are not,
but counterproductive absorption is an oxymoron.
What really throws me off is the "natural plant
lipids" which form the "basis of our nanoencapsulation
material". If water-soluble vitamins are encased in lipids (another term
for fat, or fatty acids) they are not available for transport as these
vitamins' carriers and receptors will not recognize them. If the nanocapsules,
thanks to their fat-soluble exterior, are integrated wholly into the micelles,
which transport fat and fat-soluble vitamins, then the water soluble vitamins
end up in the blood in a different pathway. If the nanocapsules are dissolved
in the intestine prior to their absorption, then what difference does nanoencapsulation
make to the absorption process. And with "difference" I mean the
difference to naturally delivered vitamins of an apple or an egg yolk which you
eat.
The rest of this quote is, like most of their page, a lot of
ballyhoo.
Now it's time to return to our initial question: Does
nano-encapsulation improve the effect of multi-vitamin multi-mineral supplements?
You probably have guessed my answer: If I had to form a hypothesis, it would be
something along the line of "nano-encapsulation in itself is not expected
to improve a supplement based delivery of vitamins. The potential benefit of
nanoencapsulating vitamins in supplements is the potentially longer shelf life
of so encapsulated products."
But this longer shelf life benefits exclusively the
manufacturer, not you, the consumer. Encapsulation or not, you'll only buy a
bottle of vitamin pills which you can consume before it's use-by date. Don't
you?
Now that you have read my point of view on vitamin
supplementation (my yesterday's post) and on nano-encapsulation of supplements,
I need to tell you why my arguments may not apply to you, personally. This is
an issue which plagues medicine and public health, and it is hardly recognized
or being talked about. This issue is at the heart of personalized medicine and
personalized prevention. Stay tuned, because I will tell you in my next post,
why you should be skeptical of the interpretation of the results of any study,
regardless of who interprets the results. Whether it's me or anybody else.
Stay tuned.
Friday, April 13, 2012
Do vitamin supplements make you healthier?
The (non-)sense of vitamin supplementation?
Almost one in two American adults is a regular user of vitamin
and mineral supplements, either in the form of single- or multivitamin/mineral
formulations (MVMS). It all adds up to a market of US$ 9 Billion annually, or
one third of the total US supplements market. Does all the pill-popping help
their users to achieve better health or longevity?
That's one question raised
by Björn, one of the readers of my blog. Thanks, Björn, I wanted to write on
this subject for some time. You just got me going on this a little earlier than
I would have otherwise. And also thanks for the second question: Does the
latest technology of delivering the drug (not to your house, but within your
body to your organism's cells) via "nano-encapsulation" improve that
health effect in any way? Let me try to answer these questions one by one.
When you talk about vitamins, you talk about essential
micronutrients, for which the human organism has either no or only a very
limited ability to produce (e.g. Vitamin D) on its own. If you want to group
vitamins according to their solubility you'll find that they come in two
flavors: water soluble and fat soluble. Of course, you could group them for any
other biochemical characteristic, but grouping them according to their
solubility makes immediate sense when you keep in mind that the fat soluble
ones (A, D, E and K) can accumulate in your body's tissues, whereas the water
soluble Vitamins typically can't. Whatever can accumulate, can also accumulate to
the point where there is too much of it in a body's tissue. So, yes, too much
of a good thing may turn into a not so good thing, as is the case for vitamins
A and E for example. Or, too much of a good thing may just be flushed out of
the body, as is the case with water-soluble vitamin C.
The supplement industry certainly does a good job convincing
the public that supplementing one's diet with additional vitamin formulations
is good for one's health. It's certainly good for the industry's bank accounts.
In such cases it always pays to ask one simple question: Where is the evidence?
In a meta-analysis of randomized clinical trials (RCT, the
gold standard of clinical research methodology), the authors investigated the
effects of vitamins E and A on the risk of cardiovascular disease and death in
altogether 220,000 patients [1].
The effects? Zilch. The authors recommendation? The evidence does not support
any recommendation for the use of Vitamins E and A. On the contrary, they found
a slight increase in all-cause and cardiovascular disease mortality associated
with vitamin A supplementation.
In another 2007 review on the subject, published in the
American Journal of Clinical Nutrition, its author came to the same conclusion,
stating that "Results to date are not compelling concerning a role for
MVMs in preventing morbidity or mortality from cancer or CVD." [2]
The two largest trials on Vitamin A and E supplementation in smokers, the
Finnish Alpha-Tocopherol Beta-Carotene (ATBC Trial) and the US Carotene and
Retinol Efficacy Trial (CARET) enrolled 29,000 and 18,000 smokers. In the
Finnish trial, supplementation with Vitamin A increased the risk for lung
cancers by 18% within a 5 to 8-year observation period [3]. And the US trial was halted
after 2 years for the same reason: a 28% increase in lung cancer risk, a 26%
increase in risk for dying from cardiovascular disease [4].
In 22,000 healthy men who had been observed for 12 years, supplementation with
vitamin A showed neither benefit nor harm [5].
So where is the evidence for you to believe that buying
Vitamin E and A supplements will make you healthier and live longer? Maybe I'm
blinded by a perverse distrust of everything a sales man tells me, but I can't
see it.
So, how about multi-vitamins? In the group of people with
the highest take-up rate of multivitamins: post-menopausal women? Again, the
authors of a study which pooled the data from the Women's Health Initiative
trial and observational study cohorts, come to the same conclusion "the WHI CT and OS cohorts provide convincing
evidence that multivitamin use has little or no influence on the risk of cancer
or CVD in postmenopausal women." [6].
Not even for infections is there any evidence that MVMS have
any protective effect on those most vulnerable, the elderly [7].
Of course, keeping all this in mind, the nagging question
remains: would there be an effect if only the delivery of the drug in the human
body was improved? After all, if vitamins are essential for survival, and if
vitamin supplementation does not improve health, then there are several
possible reasons for this observation. For instance, we might get enough vitamins
from our food, and adding vitamins has simply no effect. Or, maybe we have
vitamin deficiencies but the supplements are ineffective in delivering their
vitamin loads.
Which brings us to Björn's second question: "Does
nano-encapsulation improve the effect of MVMS?
And may I add my nagging question: Or is
"nano-whatever" just a cool gimmick of the industry to push a market,
which currently grows only moderately? In the next post (Monday 16. April) I'll try to answer this
question. So, stay tuned.
Thursday, April 12, 2012
How to get those vegetarian zealots off your back.
Does red meat kill you? Only in a vegetarian's dream!
Red meat is the favorite enemy of nutritionists nowadays. Their
studies and publications are often (ab-)used by those evangelical vegetarian
types who would love to impose their no-meat religion on the rest of us. Don't
buy it. Now let me show you how you can profess your love for steak AND support
it with the data from the same studies which the zealots use for their
vegetarian crusades.
Earlier this year Pan et al. published a study titled
"Red meat consumption and mortality" [1]. They had pooled the data of
two large prospective studies, the Nurses' Health Study and the Health
Professionals' Follow-up Study. Collectively these studies had followed 121,000
people, who were free of cardiovascular diseases at baseline, for more than 20
years. Altogether, the participants accumulated close to 3 million person years
for observation. During the observation period close to 24,000 deaths occurred
of which 6,000 were of cardiovascular causes, that is heart attack, stroke,
heart failure.
The researchers discovered that for every increase of 1
serving of unprocessed red meat per day the hazard ratio of dying from any
cause was 1.13 and the hazard ratio of dying from a cvd-cause was 1.2. That
means for every increase of a serving of red meat per day the chances of dying
from any cause and from a cvd-cause increased by 13% and 20% respectively. Those
rates were a little higher for processed red meat. To put this into perspective
the researchers also calculated that if all participants had eaten less than
half a serving of red meat per day (42g/d), 9% of deaths in men and 7.6% of
deaths in women could have been prevented. Wonderful. Sounds impressive, but it
isn't for one simple reason:
Unreliable data
acquisition. Just ask one question: how did the researchers know how much
red meat those people ate? This question cuts to the heart of many, if not
most, studies on diet-disease associations. Data on food consumption are
typically acquired through food frequency questionnaires (FFQ). These FFQs ask
you about your consumption of food items over the past days, weeks or even
months. And as you can imagine, such recall can be terribly unreliable. So much
so, that other researchers wanted to quantify this effect. So they used FFQs
and compared the results with objective quantitative measurement of energy
intake and protein intake [2].
And lo and behold, they discovered that if relative risks (such as the hazard
ratio mentioned above) were calculated from FFQs they overestimate the true
diet-disease association very severely. In fact so severe, that a hazard ratio
of, say, 2 would in reality be around 1.3.
What does that mean for a hazard ratio which is, as in the
study of Pan and colleagues, less than 1.3 to begin with? It means possibly nothing.
You certainly can't conclude from these data that red meat kills you. That's
what it means. And mind you, this
inaccuracy of FFQs shows up with recall periods of a few weeks. Pan and
colleagues had to rely on FFQs which were conducted YEARS apart. In fact, data acquisition based on FFQs is so
flawed, that the question been raised "is it time to abandon the food
frequency questionnaire?" [3]. And the authors state: "We
should be very circumspect about analyses of current studies that have used
FFQs for dietary assessment." That was 7 years ago. We still have those
FFQs and you still have the media telling you how bad red meat is for you.
And I'm going to have a real nice steak now. How
about you?