Kategori: nutrition

Shoot the messenger

The blogosphere is buzzing with new theories, discussions, disagreements and downright squabbles. What better time to look at some of the ways to make your case. There are many ways to lose an argument, these are just a few examples.
Argumentum ad hominem (to the man)
When you have no basis for an argument, abuse the plaintiff. 
Cicero 
It can be surprisingly easy to attack a person or a person’s traits rather than that person’s arguments. When arguing ad hominem you are linking a negative trait, characteristic or belief to the truthfulness of that persons claim. Contrary to what many people think, calling someone an asshat is not argumentum ad hominem. That’s just a good old insult. If however, you were to say that your opponent cannot be takes seriously because he smokes joint now and then, you are making a logical fallacy.
In the nutrition blogosphere one ad hominem argument is often repeated.
Remember Matt Stone’s “Poor Poor Jimmy Moore “ post where he linked Jimmy’s weight to the truthfulness of his weight loss claims? Although he never directly said, «Jimmy is fat, therefore his low carbohydrate diet advice does not work» – it was strongly implied.
After the death of Robert Atkins many have tried to undermine his message by referring to images showing he was not very lean.
Anthony Colpo wrote, amongst much other silliness, this about Richard Nikoley:
…apparently there is an angry post written by some overweight joker who runs what would appear from its URL to be an animal liberation blog …
Once again, Colpo did not say Richard is fat therefore he is wrong, but it was implied and could thus be filed under the ad hominem label.
A fat dietician or nutritionist is actually not any less trustworthy than a lean one, although we easily feel it is so. If you reject a person’s claim due his weight it is a logical fallacy. Sadly, when you work with nutrition, you gain more acceptance if you yourself look fit. 
Calling another person fat is only a logical fallacy if it is formulated such as: “You are fat therefore you must be wrong.” But the “therefore” can often be implied.
The above examples are forms of ad hominem arguments called “Tu quoque”, meaning “you to”.
The uncrowned king of logical fallacies and ad hominem arguments in the nutrition blogosphere is Durianrider 
Here are a few examples from his blog: 
Durianrider is the type of person who makes me want to commit logical fallacies myself. Oh, what the hell: Durianrider is an asshat, so you cannot take anything he says seriously.
Here’s another example of Tu quoque:
Bob: «Smoking is a highly addictive habit and causes health problems. You should not smoke.»
Alice: «But you yourself smoke!»
The fact that Bob smokes doesn’t mean that he is wrong about the effects of smoking.
Imagine for example that you move to a new town that has two dentists, of which one has poor teeth and one has good teeth. Who do you choose as your dentist? The one with the poor teeth of course, because chances are that he does the teeth of the dentist with the fine smile.
Similarly if you are joining a gym, join the one with the lean customers and the fat instructor rather than the one with fat customers and a lean instructor.
Overweight has a large range of causes, nutrition being but one. We all know that knowing what is smart to do is not enough to do what is smart. Especially we need to remember psychological issues that are usually at play. Overweight people can give just as good nutritional advice as lean people.
There are other forms of ad hominem arguments. If you claim that an argument is incorrect due to its source; for example saying your trainers claim that “proteins are good for you” must be wrong because the trainer sells protein supplements, it is a logical fallacy called Ad hominem circumstantial. You might want be skeptic, but scepticism it is no ground to dismiss his argument. We cannot dismiss a scientific article because it is funded by Pepsi because even Pepsi might be right.
Guilt by association can also be a type of ad hominem fallacy. An example:
Person P makes claim C to paleo blogger.
Vegans, a group which is viewed negatively (nutjobs) by the paleo blogger, also makes claim C.
Therefore, person P is also viewed as a nutjob and claim C is dismissed.
Argumentum ad ignorantiam
Appeal to ignorance – the claim that whatever has not been proved false must be true, and vice versa (e.g., there is no compelling evidence that UFOs are not visiting the Earth; therefore UFOs exist – and there is intelligent life elsewhere in the Universe. Or: there may be seventy kazillion other worlds, but not one is known to have the moral advancement of the Earth, so we’re still central to the Universe.) This impatience with ambiguity can be criticized in the phrase: absence of evidence is not evidence of absence.
Carl Sagan 
People often arrive at the wrong conclusions simply because of ignorance or lack of knowledge. A creationist may argue that evolution must be wrong based on the complexity of nature, thus illustrating his lack of understanding.
I feel that the oft-used “we don’t know the long term effects of carbohydrate restriction, therefore we consider it unhealthy and recommend against it” falls under the above category. If however carbohydrate restriction was always found to be unhealthy in short term trials, claiming it is unhealthy long term, is not a fallacy.
The argumentum ad ignorantiam can go two ways. Arguing that a central control of obesity is nonexistent because no one has proven it beyond a doubt is a fallacy. It is also a fallacy to say that a central control of obesity exist because its non-existence has not been proved.
Post-hoc ergo propter hoc
The human brain is in many ways designed specifically to se correlations and to assess causality. When the stone age man learned that bear cubs alone in the forest meant get the hell out of there before mother bear comes, it saved his life. It can also be life saving to associate the moldiness of food with abdominal pain. We look for associations everywhere and all the time, but we also often fail miserably. Correlation does not prove causation.
Many people will argue from their own experience that homeopathic medicine works, even though most studies show that they don’t. It you get well after doing or eating something out of the ordinary you are likely to believe that particular action caused the improvement rather than thinking you would have gotten better anyway. This illustrates the dangers of advise based on n=1 experimenting.
If you make the observation that fat people are more sedentary than lean people and that people are thus fat because they are sedentary, you are making a logical fallacy. There is always the chance that obesity makes people sedentary and that leanness makes people move.
When the low carber finds his symptoms of poor health disappear, he argues that carbohydrates caused the poor health. This too can easily be a fallacy.
Straw men
By reducing an opponent’s arguments into simplified versions easier to dismantle you are building straw men. Nutritional researchers are exceptionally good at making straw men. You can find several studies claiming dietary fat reduction cause all sorts of good things, even though the studies did much more than just reduce dietary fat.
Some studies claim to have disproven the effectiveness of low carbohydrate diets by using a diet with quite a lot of carbohydrates but labeling it low carb. They have then created an illusion of having refuted a proposition by replacing it with a superficially similar yet unequivalent proposition (the «straw man»), and refuting it, without ever having actually refuted the original position.
Tautology 
If you say that obesity is caused by an excessive calorie intake, this can be considered a tautology. Obesity by definition means calorie intake has been high, at least higher that calorie expenditure, so the claim is meaningless and nonsensical.
Argumentum ad verecundiam (Argument from authority)
In any decent discussion the discussing parts needs to have a certain degree of knowledge. James Krieger says Gary Taubes is wrong. As a consequence less knowledgeable people appear and say that Taubes is wrong because Krieger says so. This is a logical fallacy. Whether Taubes is right or not is beside the point.
How often do you think a politician commits a logical fallacy by arguing from authority? Whatever your view is, it is never hard to find an “expert” to lean on. In nutritional politics this logical fallacy is common. When the politician says you should eat more grain because ADA says so, this is a logical fallacy, albeit a rather necessary fallacy.
The Golden Mean
The golden mean argument bugs the hell out of me. The golden mean fallacy says that the truth must be somewhere between the extremes, often right in the middle. Most people have a tendency not to believe in anything extreme. But the truth is the truth, extreme or not.
Political correctness often ends up in a golden mean argument. Official dietary guidelines are pretty much based on the golden mean fallacy.
Argumentum ad populum (appeal to the people)
Even bad ideas and untruths can be accepted by the majority, this however does not make the idea any more valid.
All your friends say cholonics are a good idea and very healthy so it must be true, is a prime example.
I Norway, leading nutritional experts will say that almost every government in the world agrees that the human diet should be grain based, implying that it must thus be true.
In health and nutrition ad populum arguments are very common so watch out.
False Dichotomy
Saying fat is either good or bad for you is a false dichotomy, and do not believe the answer to overweight is either food reward or macronutrients.
Anyone who has worked with exercise or nutrition knows how people will make false dichotomies all the time. “Is this food healthy or unhealthy? Is this exercise effective or ineffective?”
As always, there are links in the text even though they are not highlighted by a different color. If you’d like to watch the full range of logical fallacies live, watch Fox News.

My beloved science and me

I am no expert on anything, except perhaps on being me, of which I have an entire lifetime of experience. I don’t know much about biochemistry, about anthropology, anatomy or physiology in general. I got through my entire low quality typically Norwegian education in sport sciences almost completely without taking notes (it’s difficult to listen to a lecturer, think, and take notes at the same time) and without top scores. I have a terrible memory and often read my own blog to learn new things. In fact one of the reasons I started writing things down here was simply to have a place to put down my thoughts so that I could find them again. I am no expert and no one reading this blog should make the mistake of considering anything here expert advice.

But I like science. The reason is that I’d just like to know the truth. I am not interested in believing and the only way to find truth, as far as I know, is to use science. We all start out as scientists and we all know how to use science when we are born. From day one we are doing our very own n=1 study. What happens when I eat this? What sort of reaction do I get when I pull this down? The results are recorded in neurons and we test and test and test.

After a while though the brain starts living a life of its own, and we believe things not tested, we suppose and assume and depend on rational guidance to not lose touch with reality.

The urge to believe is strong. Superstition, which is one of those evolutionary obstacles on the course to rationality, is a good example of this. You wore your blue shirt to that meeting that went just perfect, and when it is time for a new meeting there is an urge to yet again pull out the same shirt, because it might be that the shirt matters. Another great meeting and the likelihood of a different shirt being worn to an important meeting gradually diminishes. Athletes engaging in competitive sports seem particularly prone to superstitious thoughts.

Superstition still makes perfect sense in light of evolution, as most things do, but luckily we can fight even evolution. Our irrationality can also be blamed on evolution. Believing that the stars are fires on the eternal hunting grounds of the afterlife or that somehow everything is linked to a carpenter being nailed to a piece of wood for saying people should just try to get along, is believed because our brains have evolved little protection against these sorts of thoughts. But this lack of an irrationality force field can make the search for truth difficult.

I am no expert, but I’d still like to know the truth and I fight the propensity to believe every day. That being said, I don’t think you have to be an expert to understand the general theme of healthy living. Much of it makes perfect sense and much of the rest requires a strong belief held despite the nature of the evidence.

Eating foods found in nature and not those invented by humans makes a lot of sense. Not accepting this requires some faith. Eating animals also makes a lot of sense as most data suggest it to be wise, while not eating animals requires belief in something other than nature (if you ask a vegan he might say he believes in nature, but that’s just self delusion. He believes in his self delusion).

Grains worry me. Admittedly I haven’t looked at the data on this subject very thoroughly. It seems to me the data arguing against grain intake is not that strong. I would have liked to have some RCT’s and some more anthropologic data from hunter gatherers. But the data are strong enough to have me worried, and strong enough to make grains nothing more than an occasional exception to my diet.

In all likelihood you do not have to eat a low carb diet to be healthy. Anthropologic data has shown us that humans can and do live as hunter gatherers on a relatively high carbohydrate diet without being plagued by the diseases of civilization.

I feel there are two important notes shat should be made regarding optimal diets. Firstly, although humans can thrive with good health on high carbohydrate diets, this does not exclude the possibility that we can thrive even more and improve our health more by replacing some of the carbohydrate with fats and protein. The Kitawans were healthy, but could they have been healthier? Secondly, although the evidence clearly indicate a natural, Paleolithic like diet with minimal grains, plant oils and processed foods as the optimal diet for maximal health, as a (wannabe)scientist I cannot take this to mean that we will not find an even better alternative. I am, and have to be, open to the possibility that we in the future might grow meat in the laboratory that far exceeds the nutritional quality of any natural meat, that we may make genetically modified foods that should replace natural foods or that we in the end will compose our diets of highly processed even plant based foods which might be the best human diet ever achieved. Technology is cool and the speed of scientific progress is astounding. I can’t wait to see what the future will bring. For now though, natural paleo like diets are our best alternative.

Science like most human endeavors is also affected by fashion and trends. There are even scientific journal with names like “Trends in molecular medicine” and “Trends in cell biology.” The latest environmental fashion is climate, which seems to be changing rather more than most people like it to. It’s a fashion though, and I dislike the reduced focus on other major environmental disasters. Physics has string theory, which has been all the hype for some time. Paleo is a trend in nutritional science and I think leptin perhaps is losing its popularity.

Strangely, it took a fashion designer (my wife) to give me a good scientific analogy for the changing of trends and how we perceive them. Fashion is after all both defined and plagued by ever changing trends. She proposed that trends are like the ever moving tectonic plates, but there is always a constant and stable core. Sometimes we get caught up in the ways of the plates and forget about the core.

The important thing to remember about trends in science is to not confuse popularity with importance. A new and exciting theory can shift our focus like a pair of boobs passing through the vision of a human male, but its importance must be questioned.

I sometimes think that as a scientist I should be open to anything. If new data emerge from good methods they should be accepted despite any of my previous certainties. I also think that not all things need to be studied. We do not need to do a scientific study to find out if it is dangerous to jump out of an airplane without a parachute, because common sense, a well developed human ability, predict the outcome of these actions and tells us what the result might be.

Unfortunately, this view – the conviction that some things need not be tested because rationality and common sense dictate them to be true – can also be used to halt science. This has happened in some scientists who do not think any more dietary trials are necessary because we already know fat is fattening. Or that no more trials of physical activity to treat obesity are necessary because we already know exercise makes us thinner. It is common sense and regarded as established as gravity.

So we need to have an open mind, albeit not so much that our brains fall out, the prime example being alternative medicine which in all aspects apart from a deity seems equal to religion.

Nutritional science like any science is a mental obstacle course where the true way is along a rope that is not spanned high in the air, but only just above the ground. It seems intended more to cause stumbling than to be walked upon.*

*Franz Kafka

New dietary guidelines – the fairies are rejoicing

Nonsense, n; That which is not sense; spoken or written words which make no sense or convey absurd ideas; also, absurd or senseless action.

I am writing nonsense, but it is because no sense within my mind will answer the purpose. 

Hawthorne (1871) 

All around are heated discussions and angry tweeters, heads are being slammed on desks, palms being slammed on faces (preferably ones one) and Einstein’s definition of madness is being quoted frequently.

Ladies and gentlemen, I give you the new and updated dietary guidelines.

Someone once said that science pretends to be more reasonable than it is, and so ends up being more unreasonable as a consequence. I am more inclined to replace science with scientists.

There is so much to be said about dietary guidelines and I am sure much will be said in the near future. I will not go into details and argue what statements are sound and supported by science and which are not. But I do find the entire process very interesting and I wonder if a time comes when people will look back at this while giving themselves a good facepalm and thinking, “What the hell were they thinking?” I can’t wait till the future gets here.

I was at the Norwegian Health Directorate yesterday to get a copy of the new national guidelines and to hear what the perpetrators had to say. As expected, they served fruit and bad coffee. It was interesting to hear how the authors boasted about the foolproof methodology they had used. How only the best information from the best sources, like the World Health Organization and the World Cancer Research Fund, was used. It got me thinking how remarkable it is that in some peoples mind, as long as the methodology is good the conclusion is equally good. But good methodology does not translate into good science. It might help, but in the case of WCRF report, for example, it clearly did not. I checked, and it is full of arbitrary mess ups like translating correlation directly into causation, not to mention its use of thermodynamics and its cherry picking articles and miss referencing.

The Norwegian guidelines were neatly divided into 13 simple, easy to follow points (loosely translated):

1: Diet should be primarily plant based and contain lots of vegetables, fruit, berries, whole grain and fish, and contain limited amounts of red meat, salt, added sugar and energy dense foods.

2: It is recommended to maintain a balance between energy intake and energy expenditure.

3: Eat 5 portions of vegetables, fruit and berries a day.

4: Eat minimum 4 portions of whole grain products each day.

5: Eat the equivalent of 2-3 dinner portions of fish per week.

6: It is recommended that low fat dairy products be a constituent of the daily diet.

7: It is recommended that one chooses lean meat and meat products and limit the intake of red and processed meat.

8: It is recommended that one choose plant oils and margarines.

9: Drink water.

10: Limit intake of added sugar.

11: Limit intake of salt.

12: Supplements might be necessary to ensure nutrient intake for parts of the population.

13: A minimum of 30 min of physical activity per day is recommended.

There you have it. The recipe for good and healthy living. The diet should be plant based. I know there are humans in the world and even small societies that do live on a primarily plant based diet and who seemingly are in good health. But in no way does this imply that a plant based diet is healthier than one animal based. It doesn’t even prove that a plant based diet is healthy, just that it might be possible. Of course the guidelines are not based on anthropologic evidence, but on a fear of animal fat and meat. It is not based on scientific data supporting a link between the intake of animal fats and disease, but on a completely irrational fear that fat might be deleterious to health, a fear created by a wonderful combination of a scientific field consisting of people who have forgotten what science is but who are still constantly cheering each other on in close cooperation with media and marketing interests.

The one vital part missing in the dietary guideline picture is what we do when the brilliant foolproof methodology gives us a conclusion. This is not when we rest on our laurels, but the time for some actual science to take place. This is when we have to check if the conclusion makes sense in light of what we know from all the different areas of science.

There is no evidence of this last part taking place in the guideline process. But the guidelines are not worthless. In fact a good and scientifically sound way to base your diet and lifestyle would be to use the guidelines in the following way:

Mind the advice about cutting sugar as well as the advice about exercising. Don’t mind the fish and the water and the vegetables, do the complete opposite of the rest:

– Diet should be animal based.

– Grain intake should be minimal

– Butter and animal fats should be substituted for plant oils and margarine.

– Do not pay attention to energy intake and expenditure,

and remember to get enough salt.

Come on guys, you’re smarter than this

Just because a wording, written or spoken is simplified to better communicate the message at hand, it does not mean we should think simple thoughts.

When I tell my pupils that sugar makes us fat (the word fat can be replaced by sick with no consequences for the argument), they look at their bottle of coke, then down at their skinny teenager body and say, “Oh yeah! I drink a lot of soda, but I’m not fat”

I can excuse and understand the response because I know a 14 year old has too little experience in logic thought. They are on a constant pubertal high and struggles to imagine consequences beyond those of tomorrow. And they are always out to get you and prove you wrong.

Patiently, I can explain to the teenager that “…all that sugar is going to make you fat, but not instantly. Not now, but in time.” “Sugar make us fat,” does not mean “Taste sugar and expand immediately.”

I find it more difficult to excuse the adult population who has a longer track record in being exposed to logic and who are consistently being reminded of the complexities of life.

Life gets more complicated after puberty. Black and white turn into shades of grey. Not because life itself changes, but because we gradually see the complexities. Fortunately, life also gets less confusing with age, but that’s a different matter.

The Twinkie professor is losing weight while eating junk. Does this prove that junk food is not to blame for obesity and lifestyle disease? No, of course not. You are smarter than that.

– Sugar may cause diabetes.
– But many people eat high sugar diets, and do not get diabetic…
– So?

Sugar still causes diabetes. Stop thinking in absolutes. You can be smarter than that. Never mind the fact that I said “may”. We are complex organisms. Our genes differ in type and expression. We live in different environments and we feel different feelings. When too many factors coincide, sugar causes diabetes. I did not say always.

Eating a low carb diet will make most overweight people lose weight. The fact that your friend heard of a person not losing weight on a low carb diet, does not mean carbohydrate restriction is not an effective weight loss tool. Stop for a while and think. You should be smarter than that.

– Overweight may be caused by a too large intake of carbohydrates.
– But what about all those skinny Asians on a high rice diet?
– What about them?

Carbohydrates may still cause overweight and may still be the single most important factor in developing overweight. We are complex beings in a complex world. When too many factors coincide, carbohydrates will make you fat. An insufficient amount of factors have coincided in the people you are referring to. Stop thinking in absolutes. Be smarter than that.

– Grains make us sick.
– But most people here eat lots of grains and many are not sick.
– So?

Most people do not know how great they can feel, how good their heath can be. Just because you don’t consider yourself sick, does not mean your health couldn’t be much better.

Your recurring headaches, your stiff joints in the morning, your inability to concentrate, falling asleep on the couch when you get home from work, your mood swings and all the rest of those small symptoms you notice every day, but never consider to be anything but the normal state, are all signs of something being wrong. It is possible to feel great most of the time. You just haven’t experienced it yet or have forgotten Grains may be to blame for the fact that we no longer know how good we can feel as humans.

The black swan disproves the hypothesis claiming all swans to be white. Or so we are told. But the one fat person eating a low carb diet does not prove that carbohydrate restriction is not a very effective weight loss tool. It proves nothing. Stop thinking in absolutes. You need to be smarter than this.

Poppers swan example is perhaps not the best example for everyday use. If you knew there were no black swans yet encountered one during your walk by the water, you’d look for the punk with the spray can.

If most data indicate easily digestible carbohydrates as the primary cause of overweight and you see people that over time live on diets high in easily digestible carbs, yet remain lean, look for the punk with the spray can. Look for the confounding factors. There are many. The hypothesis remains.

The most horrible examples of a juvenile mind stuck in a body that has been pushed through a scientific education are found in the riders of the thermodynamic approach to weight management – those claiming overweight is caused by a too high energy intake. Those that tell you to count your calories and to calculate your energy expenditure despite the fact that they themselves have never bothered about energy in or out yet still stay perfectly thin.

In these people, the bell that should have gone off in the back of the mind is malfunctioning. Perhaps because of a lack of animal products in the diet. Perhaps because of the grains. No matter the cause, the result is an inability to see the gargantuan crack in their own wall of logic.

Stop thinking like a teenager. You have to be smarter than that.

The Twinkie professor has proven nothing and no headline has ever given you all the information you need to refute a theory.

Smoking causes lung cancer. The observation that your grandmother smoked all her life without getting cancer and dying of old age at 100 years, is not refutation material.

Jumping out of a plane without a parachute will kill you. There might have been people who have survived even this, but jumping out of a plane without a parachute will kill you. Just as grains make you sick and smoking gives you lung cancer.

The troublesome issue at hand is largely rhetoric in nature. Our constant efforts at trying to be skeptic, open minded and to prove others wrong result in alarmingly silly discussions. If each and every utterance should consider all related and relevant factors, our language will no longer be suited for communication.

“Carbohydrates may make you fat” is a better wording than, “carbohydrates may, in time, if ingested in high insulin raising form, and if ingested in the face of full glycogen stores, especially if ingested in a low nutritious form such as corns or in combination with a high omega 6 diet, and if ingested in periods of stress and in an individual whose genes make him or her susceptible to endoplasmatic reticulum stress and insulin resistance, make you fat.”

The first wording is no less correct because of its inferior word count and the sentence does not mean carbohydrates will always and under any circumstance inflate you beyond recognition upon touching your tongue. The second wording elaborates and describes very normal circumstances.

The first wording is not an absolute and if you consider it so, it is because you think in absolutes. Stop doing that. It only makes things worse.

Remember, media wants you to think in absolutes. A story considering all the factors will only appeal to the scientist and will not appear in your newspaper. This will confuse you, as the media will through using absolutes constantly contradict itself. One day carbs are good, the next day they will kill you. Stop and think. For the sake of sound minds everywhere, you must be smarter than this.

A scientist’s dilemma

I would like to consider myself a scientist – or at the very least a man of science. I do science for a living, although admittedly I don’t actually know what science is.

When I talk to people about nutrition, whether in person or in front of a class, I make an attempt at presenting nutrition from what I believe to be a scientific standpoint.
But there invariably comes a point during my rambling monologues when the listeners who aren’t sleeping realize that my advice on nutrition is roughly the opposite of what everybody else say, the opposite of what their textbooks says and the opposite of what the government recommends.

“Eat fat,” I say, “preferably saturated fat. Butter is great. Avoid sugar and eat proteins. In fact, just make sure that most of what you are eating was also once eating something. Don’t eat grains, at least no wheat. If you don’t like seafood you might want to supplement with omega 3.” You get the picture.

At this point, a hovering hand usually catches my attention.

“Are you telling us the government is wrong?”

“Yes, that is correct,” I think to myself. But I don’t say it.

Instead I try my best at working around question and feeling very much like a greased up politician I effectively avoid the question by saying something about how scientific results are often disagreed upon, how it takes time to change scientific paradigms, how textbooks are slowly updated, how science is not immune to the ways of money and how even scientists rarely admit to being wrong even though the evidence calls for it.

But, what I would like to say is, “Yes, that is correct.” In fact, what I would like to say that it is hard to be more wrong than the official guidelines.

I dodge the question, because I know I will lose credibility by asserting myself. Claiming to possess a knowledge that has escaped most everybody but me will drive my audience away and luckily so. It is after all a sign of healthy skepticism in my audience.

If I succeed in getting across the message that even the government might get it wrong, there invariably is a follow-up question.

“Who then should we listen to?”

“Me,” I think.

But I don’t say it.

Instead I talk about how, if you really want to know the truth, if you really want to know about nutrition and health, you have to read. You have to read and study and accumulate your own knowledge. Only then can you make sensible decisions about whom to listen to.

If however, you don’t want to spend your time learning about nutrition and navigating the maze of confusing information, you’ve got three more or less sensible choices:

1. You can trust your experience and the experience of those around you. A lot can be learned from listening to the body, cleaning out the senses and having a keen eye for the obvious. Humans however, are prone to deceiving themselves.

2. Find any random person or organization that promote a dietary strategy and follow it. This strategy is commonly used in religion and judging by the number of religious people around, I would say it’s an easily followable approach.

3. Don’t give a crap and eat whatever you want to eat.

I hate that there are no better options. When asked about whom to trust I would like to give people a name. Preferably the government, as it should be their responsibility to make correct and important knowledge available to the public. But I can’t give a name. In truth, the only option for those who really seek the truth is to find it themselves.

And how bloody ineffective it all is. But as I claim that those who should be trusted can’t be trusted there is no way people will or should blindly trust me.

And who’s to blame for this sticky situation? Much of the blame lies with scientists; the very group of people I would like to consider myself a part of.

Scientists have disagreed far more than the evidence permits. They have been led by money, fame and feelings and are in general guilty of being just like ordinary humans.

I do not think nor hope that the day comes when I can teach a nutrition- and health approach that everybody agrees upon. After all, the progress of science rests entirely on disagreement. But it should be possible to agree about the important issues. It is possible, but agreement honors us with its absence. And in the meantime everything is so much more difficult than it has to be and the obvious question poses a dilemma where there should be none.

The tide is turning

Ronald M Krauss, former Senior Advisor to the National Cholesterol Education Program, actively involved with the American Heart Association, former Chairman of the Nutrition Committee, has in collaboration with Siri-Tarino Patty, Sun Qi and B. H. Frank conducted meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Although I have yet to read the entire article the abstract is promising.
Twenty-one studies with 5–23 years of follow-up of 347,747 subjects gave this uplifting conclusion:
“A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat.”
I enthusiastically await the response of the nutrition community.
Abstract of article here:
http://www.ajcn.org/cgi/content/abstract/ajcn.2009.27725v1

About hunger

Much has been said about hunger. The sensation is often considered largely under cognitive control. An overweight person seeking counselling is asked to eat less, despite claiming to already be hungry most of the time. Hunger is in this case simply considered by the treating authority to be suppressed by a strong will of mind. Sadly, it doesn’t work that way.


Many theories have however been presented in an attempt to explain hunger through physiological processes. Amongst these are hunger and satiety centres, the glucostat and lipostat theory and body weight set point. Unfortunately most of these fail to explain the observations in a satisfactory way. There is however a less known hypothesis which manages to explain most observations quite well. The consequence of this hypothesis however, is that macronutrient intake may play a very important role. Not because they contain different amounts of energy, but because they influence our metabolism in different ways.


Hunger might seem easily understood, as we get hungry when we don’t eat and feel sated when we do. But this is a gross oversimplification. If we fast, we may feel extreme hunger during the first day or two, but then as ketone body production sets in and fat metabolism is up regulated, hunger is diminished despite the complete lack of food. In some cases people feel hungry most of the time and satisfying the constant hunger may cause obesity and even death. This makes no evolutionary sense. Why is a body creating hunger signals when it obviously has more than enough energy in its stores and is obviously consuming more than enough energy to maintain it’s weight? The simple answer is that stored energy is not necessarily available for use, and the amount of energy ingested also does not necessarily reflect the amount of energy available for use.

    
In the 1950s, Jean Meyer presented the glcostatic theory. This hypothesis was used (and unfortunately still is) to explain how our blood glucose level controls our sensation of hunger and satiety. It states that a low blood glucose level stimulates an increased hunger and food intake, while high glucose levels will stimulate satiety. The theory is not easily rejected and may indeed seem plausible. In early studies, scientists succeeded in inducing increased food intake in rats and increased hunger in humans, by using insulin to reduce glucose levels. In addition, hypoglycaemia (low blood sugar) in diabetes was known to be associated with increased food intake. Also, the knowledge that our brain is strongly dependant on glucose for fuel further increased the plausibility of the theory. But, although glucose level does influence our feeling of hunger it is however unlikely that it controls our total food intake and low glucose might just be an effect rather than a cause. One good argument against a glucostatic theory is that affecting fat metabolism, independent of glucose levels, can increase hunger.
As we grow our different body tissues grow in unison, but after we become adults most of the change in body size is due to changes in fat tissue size. The lipostatic hypothesis claims that any change in body fat is followed by a signal to either increase or decrease food intake.  I’ll admit that from an evolutionary point of view this seems plausible, but the number of observations that fails to be explained by this hypothesis are many. Unfortunately, many consider this hypothesis close to a fact even today, but now it goes under the name of the body weight set-point hypothesis.

One of the strongest arguments in support of the lipostatic hypothesis has been based on the hyperphagia (fancy word for great hunger or eating a lot) and obesity that result following ventromedial hypothalamic (VMH) lesions. During the 40’s and 50’s it was found that damage to specific hypothalamic areas (VMH lesions) provoked dramatic alterations in food intake and body weight. These lesions caused an increased food intake in most animals studied. As it was assumed that the hypothalamus was the control centre of hunger and satiety, the increased food intake in these studies was thus assumed to be a result of increased hunger. Also, people with the genetic condition known as Prader-Willi, are known to have a voracious appetite. This genetic condition affects the hypothalamus as well and it was once again assumed that this genetic error affected the hunger/satiety centre of the brain thus causing increased food intake.
Although VMH lesions were originally used in support of a lipostatic hypothesis, the very same studies provide evidence for the improbability of the same hypothesis. The fact that hunger occurs in rats with VMH lesions despite the presence of an internal excess of metabolic fuels suggests that the size of the fat depots becomes important to feeding only if the animal has access to them. Access is a key point here. 

It was later found that although VMH lesions did indeed cause increased food intake, the very same lesions also disrupted fat metabolism in favour of increased fat storage (partly due to increased insulin secretion) thus making fat depots unavailable. Hyperphagia has been associated with obesity and large energy storage in fat tissue, but it has also been shown that in most animal models, the increase in fat storage occurs prior to increases in food intake. In other words, increase in fat storage (the unavailability of fat for fuel) increases hunger and thus food intake. This is an extremely important point. Increased hunger may very likely be caused by increased fat storage and not the other way around, as is the general interpretation. In support of the above-mentioned, scientists has successfully increased both the power and the duration of satiety, simply by inhibiting fat storage.
Even in the Prader-Willy syndrome, the hyperphagia observed might very well be secondary to fat storage. They might be eating because they are getting fat, and not the other way around. They might be eating because most energy is locked away in fat depots, and the rest of the body is starving. Our body gets its energy either from its stores or from food. If the stored energy is unavailable the body is left with no other choice than to increase hunger. I have unfortunately only seen one study described where a low carbohydrate diet was administered to people with Prader-Willi, but it does provide some interesting clues. Remember that reducing dietary carbohydrates most often will cause a decrease in fat storage. If hunger is caused by large fat storage, reducing the storage would presumably decrease hunger, as has been done with medications in other studies. In the study described in ”The Prader-Willi syndrome”, by Holm et al it seems that carbohydrate restriction does indeed reduce hunger effectively, even in people with Prader-Willi. The mechanism behind the reduction in hunger is presumably the decrease in fat storage and thus an increased release of stored energy from fat tissue.
In the genetic rat models of obesity fa/fa rats and ob/ob rats, their defect genetics makes them overweight even with calorie restriction. The effect of their defects is an increased fat deposition. This increased storage of energy in fat tissue causes a concomitant hyperphagia and decreased energy expenditure.
Low blood sugar may also provide a strong stimulus for hunger, as the glucostatic theory claims. But, the reason for a fall in glucose levels may be caused by a low fat oxidation. If little fat is oxidized and ketone bodies are not being produced our body is more dependant of glucose for fuel, and blood sugar falls quickly. In the studies where insulin was used to stimulate hunger, it also stimulated fat storage. Insulin makes all fuels less available fore use. 
It may not even be the low glucose level in it self that makes us hungry. It may simply be the low total amount of energy available. A combined inhibition of fatty acid and glucose metabolism produces a far greater eating response than would be expected from inhibiting the metabolism of each component separately. A combined inhibition may even produce hunger when the metabolic inhibitors are given in doses that alone do not stimulate eating. This increase in food intake would not be expected if signals from glucose and fat metabolism controlled feeding independently, and indicates that changes in glucose and fat metabolism influence feeding through a common mechanism. The likely place for this regulation would be the liver.
Mark I. Friedman and Edward Stricker elucidated the mechanisms of how macronutrient composition affects hunger as early as 1976. They wrote that the stimulus for hunger and satiety were likely the result of alterations in oxidative metabolism within the liver. Their reasoning makes unnecessary previous hypothesis such as hunger and satiety centres, glucostat, lipostat, and body weight set point.
More recent work by Mark Friedman makes it clear that liver ATP production is an important regulator of hunger. Although intake of the different macronutrients affects hunger it doesn’t seem likely that quantitative changes in the use of these nutrients would provide a stimulus for hunger. Compensatory changes in the use of other fuels would limit the significance of this. It is more likely that hunger occurs whenever the immediate availability of utilizable metabolic fuels is reduced below some critical level.
The consequence of all this is that a diet with little carbohydrates and generous amounts of fat makes us lean much because this diet provides a constant flow of available energy for the liver, both from food intake and from body energy stores, and this makes us less hungry.