Phil Plait - Don't Be A Dick from JREF on Vimeo.
torsdag 7 oktober 2010
Phil Plait - Don't be a Dick
lördag 24 juli 2010
My favorite podcasts - Best podcasts
söndag 26 juli 2009
What should you believe in? Shermers Baloney detection kit
- How reliable is the source?
- Does the source often make similar claims?
- Has the claim been confirmed elsewhere?
- Does the claim fit with the way the world works?
- Has anyone tried to falsify the claim?
- What does the majority of the evidence point to?
- Is the source basing their claim on science?
- Is there positive evidence in favour of the theory (or is it only negative evidence)?
- Does the new theory account for as many phenomenon as the old theory?
- Are personal beliefs or ideologies drive the claim?
söndag 28 juni 2009
2,5 Billion(!) dollars spent on search for alternative therapies...

måndag 1 juni 2009
Truth about the Atkins diet...

Would you like to be able to eat dishes such as the one above, and get thin at the same time? According to Robert Atkins, the man behind the infamous "Atkins diet", you can. I have quite a few acquaintances who have tried the Atkins diet and quite a few of those say that it has worked rather well for them. I also know of people on whom the diet did not have a huge effect, but perhaps they have not been very disciplined?
By nature I am skeptical of anything that sounds extraordinary, and when someone comes and claims that you can eat as much meat,fat sauce, cream, chicken etc etc as you like, AND lose weight, that, to me, is an extraordinary claim! Sometimes such radical claims turn out to be right, however most of the time they are wrong...
The bottom line of the Atkins diet is quite simple: avoid carbohydrates, especially fast carbohydrates, anything else is pretty much alright. To be a bit more precise you are supposed to avoid foods that have a high "glycemic index" or GI. Products that increase your blood sugar fast have high GI (examples would be sugar, white rice, pasta, beer, etc).
According to Atkins (see picture below), his diet works because the body requires carbojydrates to store fat, in other words, if there are no carbohydrates the fat will go right through the body. This is also why, according to Atkins and his followers, you can eat as much as you like, be it the ordinary 2000 calories or even 4000 calories in one day, and you will still loose weight.
So what is the truth here? I am of course no expert on these matters, but it seems to me that accumulating evidence clearly suggests that although the Atkins diet may work, it doesn`t do it the way Robert Atkins thought it did. Rather, the Atkins diet works because you eat less when you are on it. It turns out that when the brain decides whether we are hungry or not, and in extension whether we should crawl over to the fridge and get a slice of pizza, one factor that is taken into account is peptide YY. If there is a lot of peptide YY in the body then you are full, if there is little you should eat. What causes the release of peptide YY? You guessed it, proteins does, but not carbohydrates. This means that if you eat say 1500 calories of protein then you get a lot of peptide YY and therefore you feel full and stop eating. However, if on the other hand you eat 1500 calories worth of potatoes, little peptide YY is released and therefore will still feel hungry and unless you are one of those people with amazing self control, you will keep eating... Read more about this in this article from the economist.
The conclusion that the Atkins diet works because you eat less and not because you stop storing fat has been further confirmed by a recent large Harvard study. In this study they had their subjects eat the same amount of calories, but varied the source of those calories. Some subjects were given mostly carbohydrates, some were given mostly fats, and some were given mostly protein - but all got the same number of calories. Who lost most weight? According to Atkins theory, the fewer carbohydrates you eat, the more you should loose in weight, but this was not the case. The results showed that all the different groups lost equal amounts of weight.
So the bottom line of all this is that if you want to loose weight, eat less calories. One way to achieve this is to eat a lot of protein and little carbohydrates, because you will not be as hungry...
måndag 29 september 2008
The New Testament and “Russian scandal”

It is on this last point that I want to expand here. Having recently listened to two different courses from the always fabulous "Teaching Company", one exclusively about The New Testament, and one on "The foundations of western civilization P1", I have been fueled in my skepticism towards these books as any more than a fiction which one can interpret and then depending on who you are, help you do good things or bad things. (By the way, feel free to send comments and point out if I make any blatant mistakes – I have never read the book in their entirety)
Jesus was never famous during his lifetime it seems. Apart from the bible he is barely mentioned in any historical documents. So what we know about Jesus we know mainly from the gospels in The New Testament.
Mark, which is generally regarded as the earliest of these gospels was written, according to most historians, about 70AD, that is almost 40 years after the death of Christ (the exact year of this event is also very uncertain). 40 years in an age where very few people had access to any written sources and where perhaps even fewer could read. This means that the story of Jesus must have been passed on verbally for about 30 years or so.
Anyone who have ever played Chinese whispers (I just saw that this game also goes under the name of "Arab phone" or "Russian scandal" =)), knows that this is a problem. In Chinese whispers a message is passed along in a ring eventually coming back to the person who formulated the message. The final message is compared to the original message and there is invariably an astounding difference between the two.
The normal way to play this game is to have a group of children passing along a short message, say ten words or so, with little personal significance and hence little motive amongst the children to change the message in any way. In contrast, The New Testament is a rather long message, and the people who have passed it along have had every reason to alter the story to make Jesus sound better and greater than he actually was (does anyone seriously believe that he can turn water into wine?). What would 30 years of Chinese whispers with people who would have a strong interest in changing the story do to tales about Jesus? Well, let's just say that it would be no less of a miracle should the story be accurate and precise.
söndag 7 september 2008
Popular fallacies of alternative and complementary medicine

In the most recent issue of the magazine "Skeptic", Harriet Hall, also known as "SkepDoc" writes about three fallacies that you will encounter very frequently if you engage in discussion about alternative or complementary medicine. I will of course not plagiarize Hall's article, but what I am writing here is her article, filtered through my brain (I have written about related matters here and here)...
The fallacies that you will inevitably hear are the following three;
(1) It is "natural" (and hence better for you)
(2) It has been used for a long time (and if it didn't work people would have stopped using it)
(3) It works for me (or a friend or a spouse or a friend of a friend...)
So natural is good by default ehh? In this form the statement sound very categorical, and hence, put in this fomr, the claim can be falsified by a single unambiguous counter-example, and there are plenty... Curare, a compound extracted from nature (and thus a natural compound?) will paralyze you and hence is not recommended unless you need to be still during a surgery. There are many different, naturally growing mushrooms, which will kill people who try to eat it. There is also the fen-phen scandal where a product which was advertised as an alternative medicine was later shown to have severe side effects, despite the fact that the active ingredient was "natural".

Ok, sure, there are a few extreme counter-examples, but still, isn't natural products better in general? Well this is certainly debatable and I would not jump to verdict just yet, however, the evidence to date actually tells the opposite story, namely that natural is often worse than "synthetic" (or whatever you won't to call it). Plants which are sprayed with pesticides are protected from potential predators and therefore they can use all their energy to grow. Now that I think of it, it is rather similar to us humans, in peacetime we can spend our energy on building schools and being nice to children and that sort of stuff... Plants which are not sprayed are not given their protection and therefore they have to use allot of energy on chemical warfare (or the plant-equivalent thereof). Basically they produce chemicals which will make the predator (us), sick.
But don't synthetic pesticides make you sick too? In large quantities they might (just like natural pesticides). However, pesticide control is rather strict and the chemicals used are tested so that they are of minimal danger to us... I have written more about this issue here.
The second argument says that if something has been used for a long time then it is because it is good. Again there are many counterexamples. Some people persist in using astrology even though it has been falsified over and over again. Astrologers cannot do what they claim to be able to do, and add to that the fact that their quackery is based on an astronomical model that is very out-dated. Still people are still using it… If we would have strictly gone by the "old is good" rule we would still be drilling holes in people's head to relieve headaches (here you can buy your own drill kitJ), and what about all new techniques and medicines that are developed? Are we to discard them because they are new? The fact of the matter is that we cannot rely on tradition. The way to test whether a therapy is good or bad is to do a proper, scientific test where it is possible to isolate the effect of the medicine from other factors such as placebo.
The last argument (it works for me), is the one that I have most sympathy for. In my opinion we should have respect for individual differences as well as the power of people's belief to cure them or at the very least make them feel better. If someone starts taking extra vitamins to bolster their immune system and then they do not get sick for a long time then everything is great (as long as they don't overdose which could be dangerous). Similarly, when I tell people that I am studying the brain I am often told about some therapy or mental training that I have never heard about before but which has changed their life. In those cases I normally just say that I am happy for them. However, the mistake that is often made is to assume that just because you have experienced miracles everyone else will too. Even with most conventional medicines which have a proven effect that is greater than placebo, it doesn't work for everyone. The point is that what works for you might not work for other people. Most alternative therapies have not been tested (or they have been tested with no effect). The responsible policy if you ask me is that doctors advocate therapies which have a proven effect, but do not prevent people from spending their money on other therapies (as long as they are not harmful)…
fredag 6 juni 2008
Debunking christianity

In this post I would like to promote another blog which I have just been reading. It is called Debunking Christianity (http://debunkingchristianity.blogspot.com/) and it seems to be high quality posts. Here is the authors (there are several different contributors) own description of their blog:
"This Blog has been created for the purpose of debunking Evangelical Christianity. We are ex-Christians, ex-ministers, and even ex-apologists for the Christian faith. We are now freethinkers, skeptics, agnostics, and atheists. With the diversity of our combined strengths we seek to debunk Christianity."
The reason I stumpled upon this blog was that I was investigating the birth date of Jesus Christ. In a lecture I listened to recently I heard that historical records indeed confirms that there was a census in Bethlelem. However, the census was not in year 0, but in 8BC, and it was only for Romans. And I thought that Jesus was born in year 0?
Apparently this is not the only problematic detail concerning the birth of Jesus, I qoute again from debunking christianity. The authors deserves alot of credit for the fact that they have extensive references to other texts, including the bible.
"Jesus was not born in Bethlehem, if Luke is taken literally, according to E. P. Sanders [The Historical Figure of Jesus (Penguin Press, 1993, pp. 84-91)]. What husband would take a nine-month pregnant woman on such a trek from Nazareth at that time when only heads of households were obligated to register for a census when the census would’ve been stretched out over a period of weeks or even months? But if he did, why did he not take better precautions for the birth? Why not take Mary to her relative Elizabeth’s home just a few miles away from Bethlehem for the birth of her baby? According to Luke’s own genealogy (3:23-38) David had lived 42 generations earlier. Why should everyone have had to register for a census in the town of one of his ancestors forty-two generations earlier? There would be millions of ancestors by that time, and the whole empire would have been uprooted. Why 42 generations and not 35, or 16? If it was just required of the lineage of King David to register for the census, what was Augustus thinking when he ordered it? He had a King, Herod. “Under no circumstances could the reason for Joseph’s journey be, as Luke says, that he was ‘of the house and lineage of David,’ because that was of no interest to the Romans in this context.” [Uta Ranke-Heinemann, Putting Away Childish Things, (p.10)]. The fact is, even if there was a worldwide Roman census that included Galilee at this specific time, there is evidence that Census takers taxed people based upon the land they owned, so they traveled to where people lived."
lördag 5 april 2008
Dangers of radiation in the home
The best Swedish site for news on technology, in my opinion, is www.idg.se. Today they have an article on radiation in the home. The article is based on an interview with Maria Feychting professor in epidemiology at Karolinska Institutet. The article discusses the danger of the radiation associated with products that are becomming increasingly common in ordinary homes. I am speaking of mobile phones, routers, wireless keyboards and mice, bluetooth headsets and dect phones.The conclusion of the article, briefly put, is that there are no scientific evidence that this radiation causes any harm. It is a fact that studies showing potential dangers of radiation get much more attention than studies which show zero effects, even though the latter type are much more common. Furthermore, most of the studies which have shown slight biological effects of radiation have subsequently been replicated with contrasting results i.e. the latter studies did not find any effects.
I think that one of the reasons why some people are so afraid of these things is the fact that they radiate, and we all know that radiation is bad right? No, not necessarily so. Radiation can be your friend to. If it were not for the radiation from the sun we would not be alive. Similarly, seeing involves the capture of radiation by photoreceptors in the back of your retina. In fact we are all rich sources of radiation which you can see for yourself if you have a camera that pick up infrared wavelength.

But isn't that different? Sure some sorts of radiation are more dangerous than others. Cosmic rays which arive from outer space are extremely rich in energy, and alot of that type of radiation would be bad for you. Similarly, X-rays will slightly increase the risk of cancers because it is rich in energy. But what about the radiation from all those home devices? This radiation is lower in energy than normal visual light, so you are very unlikely to get cancer from this type of radiation. These devices actually emit microwaves, just like your microwave oven. The difference is that the radiation is not contained within a box, and also the power is 10,000 smaller than in an ordinary microwave oven (for a dect phone it is 100,000 times smaller). If you want a different point of view on these issues, you can visit this page.
The article also gives some quick answers to the following questions:
1. Does radiation from mobile phones cause cancer: False
2. Will using a bluetooth headset reduce the amount of radiation you are exposed to: True (because a bluetooth headset has a much lower effect than the mobile phone)
3. A dect phone emits more radiation than a mobile phone: False
4. A 3G phone radiates more than a GSM mobile phone: False
5. More wireless devices in the home will make it more dangerous: False
6. A new router radiates more than an old router: False
7. It is dangerous to have your mobile lying next to you when you are sleeping: False
8. The mobile will emit less radiation if you hold your hand over it: False (actually it will radiate more becuase that is necessary in order to communicate the station.
9. Even the good old cable hardware emits radiation: True (anything with a current in it, a cable for instance, will generate a magnetic field which is also basically a form of radiation.

I want to end with a personal reflection on an issue which I think is highly relevant yet often forgotten. Mobile phones, which as mentioned is the device which has the highest effect and thus the highest radiation, has been around for about two decades now. In spite of their popularity, there has not been any increase in cancers in this timeperiod. This "natural experiment" shows that if mobile phones have any effect at all on the human body, that effect have to be very subtle. Pretend for a moment that there has been a slight increase in some obscure form of cancer, or other type of disease, that is a result of mobile phone radiation. Even such a necessarily slight effect would pale in comparison to the enourmous benefits of being able to call ambulances, fire fighters and the police from almost anywhere on this planet. Hurray for mobile phones!
onsdag 26 mars 2008
Medical myths
Rational as I may be I sometimes engage in superstitious behaviors because of advice I have heard a long time ago and then stuck. For example, when I have a flu I usually overdose on C-vitamin. I believe that this piece of advice was made famous by Nobel prize winning scientist Linus Pauling who asserted that C-vitamin could cure the common cold. According to other sources that I trust more on this particular issue, such as Harriet Hall, also know as the "Skep Doc", a C-vitamin overdose will at best shorten the common cold for a day, and that is for people who do not eat a lot of C-vitamin in the first place (I am one of them why I may perhaps benefit somewhat), at worst a C-vitamin overdose can make you quite sick.Two other behaviors which I sometimes engage in is drinking coca cola when my stomach is upset, and eating garlic when I have the common cold. Quick google searches did neither prove or disprove the efficiency of these two questionable treatments. Perhaps someone out there know something about it (in which case I hope you will share your knowledge).
What I really wanted to write about in this post is an article published in the British Medical Journal in which widespread myths, often reinforced by doctors were punctured. Some of these myths I believed in firmly until I saw the article. For example I have thought for a long time that reading in dim light is bad for your eyes. Now, becuase of this article, I know that there is no good evidence to back this claim. I had been wrong, but now I have changed my provisional world model to fit the new data (I stand corrected to put that more simply).
However, I am proud to say that I never bought into the myth that you only use 10% of your brain. Then again, I am a brain researcher so perhaps I cannot brag to much about this accomplishment. The idea, though popular in books such as Uri Geller's "Little Mind Power Book", is completely absurd. Would evolution allow 90% of our brain just sit there and do nothing, I think not. By the way, the claim can be easily disproved by sending a person into an FMRI and watch how the entire brain lights up which is an indication of energy expenditure (maybe with the exception of people like Uri Geller). Furthermore, in contrast to predictions of the "we only use 10% of our brain" hypothesis, removal of almost any part of the brain will result in clear symptoms,

The entire list of medical myths which are debunked in this nice article are as follows. Take a look at the article if you are not willing to take my word for it (there are nice references as well).
1. People should drink at least 2,5 litres of water per day
2. We only use 10% of our brains
3. Hair and fingernails continue to grow after death
4. Shaving hair causes it to grow back faster and be coarser
5. Reading in dim light ruins your eyesight
6. Eating turkey makes people especially drowsy
7. Mobile phones cause electromagnetic interference in hospitals
torsdag 28 februari 2008
Dihydrogen monoxide...

- Is a highly reactive chemical
- Is one of the main waste products from nuclear power plants
- Is used in the production of pesticides and is an ingredient in spray oven cleaners (!)
- Has been used by ALL students responsible for school shootings in the United States in the past
- Is used by athletes to improve performace
- Contributes to the greenhouse effect
- Have been found in large amounts, in children who live near factories
Trust me, the list goes on and on. If you don't trust me, listen to this girl at you tube, or visit DMHO facts, or "Ban dihydrogenmonoxide".
Fooled? I hope not, though if you were you are certainly not alone. The common name for dihydrogen monoxide, or DMHO, is water (di=two, mono=one, two hydrogen and one oxygen makes H2O=water). This hoax which I rate almost as highly as the Sokal hoax which I have written about here, was popularized by a 14 year old american high school student as a part of a science project. He came up with this alternative name for water and listed statements such as the ones above, all of which are of course true. He then went around and asked fellow student to sign a petition to ban DMHO, 43 out of 50 signed it.
According to wikipedia more influential people have also been fooled. In 2001 A staffer at the New Zealand green party was asked to support the campaign to ban dihydrogen monoxide, in response she wrote that she was "absolutely supportive of the campaign to ban this toxic substance". In New Zealand 2007 (are they lacking scepticism in New Zealand?) Jacqui Dean a member of parliment wrote to the health minister asking whether there were any plans to ban DMHO.
I think that this hoax illustrates that scepticism is more often than not a virtue. This hoax was very transparent compared to many of the stories that are circulating in the world which are also not true, and yet, people fell for it.
måndag 31 december 2007
Superstition in Hollywood

Last night I went to see the new animated "Bee movie". It was a cute entertaining movie and I would recommend it to anyone, however, one thing in the movie bugged me =). In the very beginning of the movie there was a black screen and on it they wrote the infamous myth that "According to all known laws of aviation the bee should not be able to fly, but unaware of this fact, the bee continues to fly anyway.
This is of course nonsense, and it annoys me a little bit that they could not do a Google search to find out whether their claim is true or false… So Seinfeld, if you read this, Bees have been studied intensively, and according to the laws of aerodynamics they can fly. The citation above is based on the assumption that insects fly like airplanes and thus need same wing-area, an assumption which is simply not true. Bees and insects in general are small compared to airplanes and they accomplish their lifting force in qualitatively different ways. We do not know the details of how all insects fly, however, bees have in fact been studied rather intensively, and they can fly. If you are still in doubt take a look at any one of these links:
Caltech – Transcript of the original research
Wikipedia – Go to "bee flight"
Ask Dr. Galapagos – Detailed analysis of this question
Skepticality discussion board – Discussion on all explicit and implicit claims in Bee Movie
Seinfeld and his friends are hardly the sole perpetrators when it comes to spreading superstitions. I have always been a fan of the series X-files. In the X-files (which I have heard is based on real cases) you have two FBI agents, Mulder and Scully. In a typical episode Mulder and Scully gets a case with weird circumstances and they go to investigate. Mulder always come up with a supernatural explanation, often involving grey aliens with pear-shaped heads, whereas Scully always comes up with a scientific explanation involving hallucinations and rare scientific phenomenon. Sounds like a perfect setting right?

The only problem is that in every episode Scully's scientific explanation is always ridiculed. In the series you often see the supernatural events actually occurring, sometimes they happen right in front of Scully, and yet she sticks with her scientific dogmatism – looking really dumb in the process.
My worry here is simply that a lot of people will walk away from their screens believing that scientists are extremely narrow minded people, even though they are not. I would bet that no scientist would ever claim that bees cannot fly – we see that they do. Just because there currently is no satisfactory theoretical explanation for a certain phenomenon does not mean that one has to deny its existence, and I don't know any scientist who would think like that. As a student of the brain I constantly come across examples where a phenomenon has been detected "e.g. consciousness", and yet there is no good theoretical account of how that phenomenon is caused. Much of science is devoted to finding such explanations – how are bees able to fly even though they have so small wings?, how does this thing that we call consciousness come about in the brain? Scientists do not deny inexplicable phenomenon, they study them and try to come up with an answer, a noble endeavor indeed.
Ps: My productivity has been a little poor lately. The reason is simply that I have been extremely busy. My blog is not about to die…
fredag 5 oktober 2007
Complementary and alternative medicine - Spontaneous recovery from disease

Alternative and complementary medicine refers to products and practices which are not part of the standard medical procedure that you get when you go to a hospital. Though the terms are often used interchangeably, alternative refers to when a practice aspires to replace standard medical care whereas complementary practices only aspire to complement standard medical procedure. For sure, for sure, medical research is far from a complete understanding of the physiology and anatomy of humans, and there are almost certainly many effective remedies which are not a part of the standard repertoire today. In the future we will no doubt see many advances in science and in consequence, new therapies to treat disease.
Having said this, complementary and alternative medicine suffers from what I consider to be a much more serious problem. First of, many of the techniques and practices used in alternative and complementary medicine have never been tested, or have not gained any support, in controlled studies and hence they have never proved to have any "real effect" (as opposed to placebo effect which they probably do have). Even more serious, because alternative therapies have often not been tested properly, it is hard to tell whether they have any serious side effects. What is almost certain is that if a particular substance has any effect at all, then it is more than likely to have side effects as well (see table at bottom of this article).
Sometimes alternative practices turn out to be effective and when they do they are eventually assimilated into standard medical practices. To be fair, this assimilation process can sometimes be agonizingly slow and some doctors are probably too conservative, however, the essence of the matter is that when an alternative treatment or therapy has gained enough support in studies it will cease to be "alternative" and become "standard". This is to some extent true for acupuncture, which is now used occasionally as a treatment for various conditions even though it has long been controversial. However, importantly, the mechanism that makes acupuncture work seems to be different from what has been claimed by those who have used this procedure in the past. No meridians have ever been demonstrated. Instead it seems that acupuncture stimulate pain sensing nerve endings. These nerve endings in turn exercise a form of lateral inhibition meaning that they block other pain sensing nerve endings around them, thus preventing the patient from experiencing pain in that area.
Complementary and alternative practices can often give the illusion of being effective because we recover spontaneously from diseases. We have an impressive immune system, which deals with seemingly limitless pathogens in an extremely efficient and competent manner. I am making up the numbers here, but say that after taking a certain herb 90% of all people recover from the flue within a week. Wow, surely there must be something to it then? But wait a minute. Almost everyone (say 90%) recovers from the flue within a week if they just stay home in bed. Suddenly these herbs do not seem that fantastic, and they seem even less attractive if you take into account the often excessive price tags.
Back pain is another example that deserves mention, and these figures I am not making up (they come from a lecture I attended recently). Nine out of ten (90% that is) cases of acute back pain will go away after one week. Combine this with the fact that 60-80% of all individuals will experience back pain sometime in their lifetime and what you get is an awful lot of cases of back pain that goes away in one week. Not surprisingly, at least not to a cynic like me, there are a huge number of alternative or complementary therapies for back pain, and they all seem really successful as long as you do not compare them to no treatment at all…

Here is my advice, my alternative therapy if you like. If you experience back pain, and don't have any other serious symptoms such as your vertebrae penetrating your back muscles (in which case I would advice going to a doctor), don't spend your money on all sorts of alternative/complementary therapies, rather relax for one week and see if the pain simple goes away (in most cases it will). Once you have recovered, use the money you would have spent on a therapy on something nice, such taking your girlfriend to a cozy restaurant. If the pain does not go away after one week, go see a doctor and have your back checked up…
Writing about alternative medicines is something that really warms my heart. I have written about homeopathy here, here and here, and here I have written about the role of the placebo effect.

