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Tuesday 28 May 2013

The Truth Was Still Putting on its Shoes - How Pseudoscience Came to Dominate the Concept of Healthy Eating

Imagine you could restore health and lose weight by eating fats and protein and consuming fewer carbohydrates, i.e. sugar and grains. This was standard medical advice up until the late 1970s. Then the advice changed to “eat more grains and limit saturated fats”. The new “healthy eating” advice was never subjected to rigorous testing before the old advice, which had served society well, was ignominiously dumped. Are we, as a nation, now fitter, better nourished, and less disease prone as a result?

The Kiwi ANZACs, widely considered to be the fittest troops in the Allied armies in two world wars, were raised in a nation where per capita weekly butter consumption was 415 grams. It is now 112 grams, which is half of the reduced 1940s wartime ration. The consumption of fat from red meat has also decreased as drastically. We eat fewer eggs and drink less full-fat milk. 

There is a fallacy that stems initially from the Western intellectual's sense of cultural inadequacy and guilt, and the assumption that Eastern cultures must somehow be purer and wiser. One of the features of Eastern religious culture identified early on by aficionados like Schopenhauer – because the things that are unusual in a culture attract attention first - was vegetarianism. The reality of Buddhist and Hindu society, like all successful human society, didn't involve denial of animal foods (the Dalai Lama eats meat, observant Hindus cook with butter fat), but the ideal, already present in Western ascetic tradition and not associated there with robust physical or mental health, had a persistent appeal, which found expression in the early temperance, vegetarian and vegan movements.

We then come to a point in history - the 60's - 70's counterculture - where the idea took hold more widely, through music and other popular media, that vegetarianism (and other aspects of Eastern religious thought) represented the higher path, while the habits of the older generation were anathematized; including church-going, smoking, drinking, meat eating. 

Various influential people exposed to this assumption in their formative years unconsciously accepted it as factual.  The same bias can be seen to persist today when veganism, despite its risks, is accepted as normal by government dieticians as somehow being worth nurturing as the expression of a noble and virtuous impulse; whereas the Atkins type of high fat, low carb diet is not to be encouraged, despite the scientific evidence in its favour and common-sense assessments of its nutritive value, because it is seen as self-indulgent. Deep psychological forces decide the values different foods are given, and mystical, revolutionary, and puritanical impulses as well as economic and social pressures distort the collection, interpretation and publication of data.

Scientific research has been misinterpreted to reflect an existing prejudice, and this has suited the food manufacturing industry, with novel oil, grain, and soy products to find markets for. A perfect storm of error has formed around the question of fat, because of the earlier invention of the cholesterol test, which seemed to support the new belief, and which lent it a spurious validity. The animal fat in our diets has been the ultimate casualty.

Most people cannot stay vegetarian for good reasons, and many backslide, but not all the way, only to the "vegan meat" chicken, to lean meats, low fat dairy and so on. It's as if by avoiding what one thinks is "saturated" fat one can avoid the sinful aspects of consuming flesh. The very word “saturated”, a technical description of chemical bonds, conveys unintended connotations of excess.

Yet highly saturated fats like beef dripping and coconut oil have a remarkable ability to protect the liver from the toxicity of alcohol or other drugs. Polyunsaturated fats have the opposite effect. That seems like something that should be more widely known, instead of confined to those medical journals that specialize in alcoholism. It should also be more widely known that people who eat the most dairy fat have half the diabetes incidence of the people who eat the least, or that, all over the world, those who attempt suicide tend to have significantly lower cholesterol levels than those who do not. And so on.

It was studying the life cycle of the hepatitis C virus (HCV) that eventually forced me to question my received beliefs about fat, carbohydrate, and cholesterol:
-  HCV depresses and monopolises cholesterol production; cholesterol in the diet counteracts  this.
 - HCV uses VLDL to exit infected cells; starches and sugars increase VLDL production. 
- Saturated fats in a low-carbohydrate diet (and omega 3 oils from fatty fish) decrease it.
 - HCV infects new cells through the LDL receptor; polyunsaturated vegetable oils increase the number of LDL receptors. 
- If you have Hepatitis C, your prospects improve with higher LDL levels (a sign of fewer LDL   receptors).
 - HCV depresses immunity by sequestering zinc and selenium; these minerals are most easily
 absorbed from fatty foods like meat, seafood and Brazil nuts; their absorption is inhibited by most grains and legumes. 
- The antioxidants from leafy vegetables, fruits and berries are valuable, but they are no substitute for animal fats and carbohydrate restriction when it comes to clearing a fatty liver,  reducing viral replication, or preventing disease progression. 

In the case of at least two diseases, the not uncommon ones of hepatitis C and alcoholism, the two main causes of cirrhosis and primary liver cancer in this country,  current “healthy eating” advice can only be increasing harms. Fast food is not so different; fries are vegetable starch cooked in polyunsaturated vegetable seed oil, supposed to be a healthy alternative to animal fat because it “lowers cholesterol”.

Nutritional epidemiologists write papers about the French paradox, whereby the French, who have largely preserved their traditional diets, diets which happen to be rich in animal fats, have relatively low levels of heart disease, and also low rates of liver cirrhosis relative to the amount of alcohol consumed in France. In the case of the Israeli paradox, this health-conscious population has adopted modern ideas about healthy eating, especially that of reducing saturated fat by substituting polyunsaturated vegetable oils for animal fats, and now has relatively high rates of cardiovascular disease, diabetes, obesity and cancer. That these results are considered paradoxical because they contradict unproven assertions should be an embarrassment to science. 
(paradox, n. Statement contrary to received opinion; statement that, whether true or not, seems absurd at first hearing; person or thing conflicting with preconceived notions of the reasonable or possible.)

Knowing all this, and also considering what our hardier ancestors might once have eaten, and what they could not have eaten, takes us back to the days before the cholesterol craze, before the food processing industry cashed in on vegetarian values, before dieticians became anserine media hacks. Sugars, grains and legumes, and seed oils, as well as the vast array of novel foods made with them, are worth limiting or avoiding. To avoid obesity, to treat diabetes and degenerative diseases, restrict carbohydrates. Fat is your friend, cholesterol is an essential part of your body, and animal foods are the most nutritious foods, with vegetable foods as valuable supplements. 

Inquiry into diet has always been part of the philosophical tradition, for example in the writings of Lucretius, Montaigne, Lichtenberg, Schopenhauer and Nietzsche, because nutrition science is, or should be, concerned with the same questions as philosophy; how do we know what we know?, and, how should we live our lives? The well-designed experiment that can settle a question will always be a commodity that is valuable precisely because it is rare. Since the existence of the deficiency diseases and the harmful effects of smoking and excessive alcohol consumption were proven many years ago it has become unusual for diet and lifestyle studies to generate results that justify sweeping statements or universal recommendations. Nothing in biology makes sense except in the light of evolution, and it is only in the light of human evolution that we can hope to make sense of the human diet and its link to disease.

Originally published in the Café Reader, a fine literary magazine produced by the New Zealand-based company Phantom Billstickers. 

Sunday 19 May 2013

Does Aspirin Prevent Liver Cancer, and, Does Ginkgo Extract Cause It?

Aspirin (acetylsalicyclic acid) is one of those drugs that blurs the distinction between the natural world and the products of human ingenuity, being a barely-tweaked analogue of salicylic acid. Salicylic acid is not only prevalent in the diet, it appears to be synthesised endogenously in fasting states.
(music: Seven Fishes by Jigsaw)

Aspirin has long been regarded ambivalently in medicine. On the one hand it kills pain and reduces fever, on the other hand excess can make the gut bleed and damage the kidneys, and even cause hepatitis. Low-dose, buffered aspirin is commonly used as a preventive of heart attacks and strokes, but its overall effectiveness in this role is questioned:

Meta-Analysis of Multiple Primary Prevention Trials of Cardiovascular Events Using Aspirin

The meta-analysis suggested superiority of aspirin for total CV events and nonfatal MI, with nonsignificant results for decreased risk for stroke, CV mortality, and all-cause mortality. There was no evidence of a statistical bias. In conclusion, aspirin decreased the risk for CV events and nonfatal MI in this large sample. Thus, primary prevention with aspirin decreased the risk for total CV events and nonfatal MI, but there were no significant differences in the incidences of stroke, CV mortality, all-cause mortality and total coronary heart disease.

So the findings in this survey were unexpected:

Nonsteroidal Anti-inflammatory Drug Use, Chronic Liver Disease, and Hepatocellular Carcinoma

Background Nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to reduce chronic inflammation and risk of many cancers, but their effect on risk of hepatocellular carcinoma (HCC) and death due to chronic liver disease (CLD) has not been investigated.
Methods We analyzed prospective data on 300504 men and women aged 50 to 71 years in the National Institutes of Health–AARP Diet and Health Study cohort and linked self-reported aspirin and nonaspirin NSAID use with registry-confirmed diagnoses of HCC (n=250) and death due to CLD (n=428, excluding HCC). We calculated hazard rate ratios (RRs) and their two-sided 95% confidence intervals (CIs) using Cox proportional hazard regression models with adjustment for age, sex, race/ethnicity, cigarette smoking, alcohol consumption, diabetes, and body mass index. All tests of statistical significance were two-sided.
Results Aspirin users had statistically significant reduced risks of incidence of HCC (RR = 0.59; 95% CI = 0.45 to 0.77) and mortality due to CLD (RR = 0.55; 95% CI = 0.45 to 0.67) compared to those who did not use aspirin. In contrast, users of nonaspirin NSAIDs had a reduced risk of mortality due to CLD (RR = 0.74; 95% CI= 0.61 to 0.90) but did not have lower risk of incidence of HCC (RR = 1.08; 95% CI = 0.84 to 1.39) compared to those who did not use nonaspirin NSAIDs. The risk estimates did not vary in statistical significance by frequency (monthly, weekly, daily) of aspirin use, but the reduced risk of mortality due to CLD was statistically significant only among monthly users of nonaspirin NSAIDs compared to non-users.
Conclusions Aspirin use was associated with reduced risk of developing HCC and of death due to CLD whereas nonaspirin NSAID use was only associated with reduced risk of death due to CLD.

Now, these are huge correlations, especially when you consider that the use of NSAIDs is considered to put one at risk of leaky gut syndromes, and that SIBO and endotoxaemia are proving to be significant factors in the development of chronic liver disease. When epidemiology goes so strongly against the grain of one's expectations, one really should sit up and take notice. There's an extra convincing feature here - the differential correlations of aspirin (less CLD, less HCC) and other NSAIDs (less CLD but no reduction in cancers). If the result was co-incidental (people with better liver function more able to use NSAIDs, for instance) this difference shouldn't exist. Non-aspirin NSAIDs lumped together by the methodology include (are mainly) ibuprofen and paracetamol (acetaminophen) and the latter can cause liver damage by depleting reduced glutathione. This has cancelled out the anti-cancer benefit (we might hypothesise) but the aspirin-like anti-inflammatory effects of ibuprofen still show.

Of course if you already have low platelets and poor blood clotting due to cirrhosis it might be a bit late to take any advantage you might see in this research. However, there is an alternative theory; that Aspirin should be considered as a salicylate supplement, and that fruits and vegetables, which are naturally rich in salicylate, can supply the same benefit. Wiki lists the sources thus:
Unripe fruits and vegetables are natural sources of salicylic acid, particularly 
blackberriesblueberriescantaloupesdatesraisinskiwi fruitsguavasapricotsgreen pepperolivestomatoesradish and chicory; also mushrooms. Some herbs and spices contain quite high amounts, although meat, poultry, fish, eggs and dairy products all have little to no salicylates. Of the legumesseedsnuts, and cereals, only almondswater chestnuts and peanuts
 have significant amounts.

Almonds just got interesting again...
Some people are intolerant of salicylates. These people may have little need for aspirin anyway if blood salicylate levels are naturally high. Removing 75% of salicylate from the body involves conjugation with glycine (requiring pantothenic acid - vitamin B5 - plus sulfur, as acetyl CoA), and clearance of salicylate might improve on a paleo diet with bone broth to supply glycine, and low carbohydrate intakes to stimulate trans-sulfation and acetyl-CoA synthesis.

Anyway the take home message from the Aspirin study as I see it - if you're concerned about the health of your liver, and your platelets are still in the normal range, you needn't be afraid to use aspirin. Though it might be a good idea to also ensure you're getting enough vitamin K.

Ginkgo Biloba Extract and Cancer

It's a common enough fallacy that natural medicines, especially ones in common use, can't be as harmful as pharmaceuticals. The appeal to nature, the appeal to antiquity, and all that. The fact is that the supplement industry is very poorly regulated in most countries, and no-one has yet worked out how to regulate it in a way that consumers, long used to experimenting freely with often cheap and sometimes effective natural medicines, will tolerate. It doesn't help that regulation is usually the business of government agencies that are seen, with some reason, as being in the pocket of Big Pharma. A few weeks ago Stephan Guyenet tweeted about this study (PDF) which shows commercial ginkgo extract is highly carcinogenic in rats and mice. 
Liver: The incidences of multiple hepatocellular 
adenoma, hepatocellular carcinoma, and hepatoblastoma 
were increased in all dosed groups of males; multiple 
hepatocellular adenoma incidences were increased in all 
dosed groups of females, and multiple hepatocellular 
carcinoma and hepatoblastoma incidences were 
increased in 600 and 2,000 mg/kg females. When single and multiple neoplasm 
incidences were combined, significant increases were 
seen in the incidences of hepatocellular adenoma in 
200 mg/kg males and all dosed groups of females, 
hepatocellular carcinoma in all dosed groups of males 
and 2,000 mg/kg females, and hepatoblastoma in all 
dosed groups of males and 600 and 2,000 mg/kg 
females. These significantly 
increased incidences also exceeded the historical control 
ranges for these neoplasms from corn oil gavage studies 
and all routes of administration (except for hepatocellular adenoma in 200 mg/kg females) 
(Cancers were also found to be significantly increased at a number of other sites including the nose and thyroid).

One could take this with a grain of salt, rats being rats, and the doses being a little higher than human doses, but the paper does refer to human trials, and these results too give cause for concern.

Two epidemiological studies explored carcinogenicity 
associated with use of Ginkgo biloba supplements. In a
population-based, case-control study reported by Ye 
et al. (2007), in which the case group included 668
women in Massachusetts and New Hampshire 
diagnosed with epithelial ovarian cancer matched to 
721 women in the control group, an inverse association
(OR=0.41; 95% confidence interval, 0.20-0.84; P=0.01)
was found between Ginkgo biloba use and risk for 
ovarian cancer. A more recent study by Biggs et al. 
(2010) used data from the largest epidemiological study
of Ginkgo biloba efficacy (Ginkgo Evaluation of 
Memory Study) conducted to date to analyze cancer as a 
secondary endpoint. The study population consisted of 
3,069 participants, age 75 years or greater, that were 
randomly assigned to receive twice daily doses of either 
a placebo or Ginkgo biloba extract (120 mg EGb 761®) 
and were followed for approximately 6 years. 
Researchers found an increased risk of breast (hazard 
ratio, 2.15; 95% confidence interval, 0.97-4.80; P=0.06) 
and colorectal (hazard ratio, 1.62; 95% confidence 
interval, 0.92-2.87; P=0.10) cancers and a decreased 
risk of prostate cancer (hazard ratio, 0.71; 
95% confidence interval, 0.43-1.17; P=0.18) in the 
population receiving Ginkgo biloba extract.

It seems to me that a more than doubled incidence of breast cancer in a randomized controlled study is the kind of result that should have been more widely discussed than it was. If this happened in a study of statins or aspartame, the whole internet would be abuzz with it. Why does Ginkgo get a pass?
Ginkgo Biloba leaf extract is not a traditional Chinese medicine. There is some mention of monks at some time making tea of the leaves, but they do not appear in any TCM formulary that I have perused. The seeds appear occasionally but are recognized as toxic and their use is rare. Ginkgo leaf extract contains many worthwhile compounds (I could fill another post with these), and it's the best treatment I know to give someone who has memory impairment from chronic marijuana use. It has a potent antifibrotic effect and has been used in modern Chinese hepatitis therapies. It will inhibit many cancers in vitro (the difference can be small between what might cause cancers, and what might treat them; some chemo drugs, as well as radiation, are carcinogenic). I used to take Ginkgo regularly every now and then. I'll still take it when I have to drive long distances, on the principle that the increased alertness will reduce risk in the short term without exposing me to longer term risk.
 is a mixture of many different types of phytochemical, and some might be more effective once isolated. It seems likely that the carcinogenic component will be identified and removed from extracts, hopefully sooner than later. The uncritical acceptance of the idea that whole herbal extracts are intrinsically more effective and safer than isolated compounds may have been mistaken in the case of Ginkgo.
Well, here we have a drug that might be better for us than was previously thought, and a popular herbal product that might actually be harmful in its present form.

What is the world coming to?

Monday 13 May 2013

Letters to the Editor

     The letter to the editor is a miniature literary form like the haiku, and one more transient than the blog post. I have written a great many over the years; no-one taught me, I believe that no university or technical college teaches the art that I have acquired "by doing".
     When you write to the editor you are constrained in time; your letter must be promptly relevant to a published letter or article. You are constrained in subject; you must rehearse the points raised and your own must be relevant to them. You are constrained in space to a paragraph or so, and you are equally constrained in style. Admittedly a smaller newspaper which I read in Tauranga has taken to publishing text messages with all their barbarous orthography intact, but a letter to an august organ such as the New Zealand Herald, with a circulation of over 500,000, must be a regular English prose composition (though if you can't quite manage that but still have something to say, the sub-editor may be generous with their aid).     
     Grandstanding, quirkiness, abuse, bare-faced flouting of logic, use of the word teh, substituting $ for S, multiplication of the letter K, obscenities, gratuitous offensiveness, and all the other tools of the blogger's trade will not be countenanced by the ladies and gentlemen of the press.
     My recently published letter was in response to one on the subject "Tackling Obesity" by one Peter Davis. It was reasonable enough and noted as I have done the sad decline in our once-great nation's health. The writer wondered if our armed forces might one day run out of healthy recruits. My first impulse was to respond that, obesity epidemic or not, the New Zealand defense forces will always be able to find the 18 or so recruits they need each year from a population of 4,405,200 at last count. However, I decided to drop the cheap joke to focus on a better target, a reference to eating too much and not exercising enough as causes of obesity. Really one can build a great deal around a light slap at this notion.
     This is my letter as it was published on Monday, May 13th:

    Peter Davis is right to insist that the social and health costs of the obesity epidemic require action. 
    Any measures taken should first increase research, while in the interim promoting the most successful overseas interventions, at present low-carb and ancestral diets, and developing them to suit New Zealand's needs. 
   It is presumptuous to say that obese people have eaten more and exercised less than others. First, such behaviour does not always result in obesity. Secondly, if I weighed an extra 45kg I would automatically be exercising a great deal harder than I do today just to go about my life, and this would probably require extra nutrition.
    Perhaps it is the declining quality of food - particularly the substituting of cheap starches, sugars and oils for nourishing fare - which is more than anything responsible for the declining quality of health in this area.

Yours Faithfully,

George Henderson

Native Diet mussels dish

And this is the letter as I sent it. I am including this version so you can appreciate how lovingly the sub-editor refined and polished my points, erased my mistakes, and improved upon my style, still slightly imperfect after all these years.

Dear sir/ma'am,

Peter Davis is right to insist that the social and health costs of the obesity epidemic require action. To avoid making things worse any measures taken should first increase research, while in the interim promoting the most successful overseas interventions, at present low-carb and ancestral diets, and developing them to suit New Zealand's needs. It is presumptive to say that obese people have eaten more and exercised less than others. Firstly, such behaviour did not, and does not, always result in obesity. Secondly, if I weighed an extra 100 pounds I would automatically be exercising a great deal harder than I do today just to go abut my life, and this would probably require extra nutrition, especially if the food available was of poor nutritive quality.
Perhaps it is the declining quality of food, i.e. the substituting of cheap starches, sugars and oils for nourishing fare, that is more than anything responsible for the declining quality of New Zealanders' health in this area.

Yours Faithfully,

George Henderson

Notice that, as New Zealand went decimal in 1967, a fact I had forgotten due to my excessive reading of U.S. diet books and blogs, my reference to a round 100 pounds was converted to a rather clunky 45 kilos.
What I believe distinguishes this letter from my earlier published efforts is the sheer number of concepts I was able to address. Unintended consequences ended up on the cutting room floor, but I was able to retain
- scientific research as the proper basis for policy decisions
- the paramount effectiveness of low-carb and paleo (without claiming that current options are perfect)
- a subtle reference to "The Native Diet"* T.V. program and other local initiatives
- a Taubesian dig at CICO
- a reference to empty calories (food quality)
- a swipe at the 3 Paleo devils, grains, sugars and oils, ignoring the expected whipping boy, my buddy fat.
And really, that's enough to be going home with.

* "The Native Diet is a concept derived from traditional Māori eating, activity and the 1920′s research of Dr Weston Price, who after visiting 14 indigenous nations including Māori, concluded the western world must look back at the traditional diets of these people groups for the future health of the next generation. Price advocated prohibiting processed foods from diets of Americans, something that has not been followed up."

Friday 3 May 2013

"The Truth was Still Putting on its Shoes", my first article to be published IRL

I haven't had my Diet Wars writing published before, unless you count my many letters to the editors of The Herald, Listener, and Otago Daily Times, letters which, I'm pleased to say, do often get published.
This is the first hard copy of an article that wasn't just a response to some piece of stupidity in the press.

It was commissioned for inclusion in the first edition of the free Café  Reader. This will hopefully be available in every café in New Zealand. Apart from my polemic, it also contains writing from the finest local talent. I opened it at random (after checking my piece for typos, phew!) and Simon Sweetman's party piece is the funniest thing I've read in ages. Put together by Phantom Billstickers, thanks to Jim and Kelly Wilson and no doubt other committed team members that I haven't had dealings with.

And there we have it. I will reprint the whole article in a few weeks for overseas readers.

Meanwhile, some exciting science news; expert scienticians have finally invented a high-fat diet that DOESN'T produce fatty liver in Wistar rats, even with prodigious overfeeding!

Long term highly saturated fat diet does not induce NASH in Wistar rats


Understanding of nonalcoholic steatohepatitis (NASH) is hampered by the lack of a suitable model. Our aim was to investigate whether long term high saturated-fat feeding would induce NASH in rats.


21 day-old rats fed high fat diets for 14 weeks, with either coconut oil or butter, and were compared with rats feeding a standard diet or a methionine choline-deficient (MCD) diet, a non physiological model of NASH.


MCDD fed rats rapidly lost weight and showed NASH features. Rats fed coconut (86% of saturated fatty acid) or butter (51% of saturated fatty acid) had an increased caloric intake (+143% and +30%). At the end of the study period, total lipid ingestion in term of percentage of energy intake was higher in both coconut (45%) and butter (42%) groups than in the standard (7%) diet group. No change in body mass was observed as compared with standard rats at the end of the experiment. However, high fat fed rats were fattier with enlarged white and brown adipose tissue (BAT) depots, but they showed no liver steatosis and no difference in triglyceride content in hepatocytes, as compared with standard rats. Absence of hepatic lipid accumulation with high fat diets was not related to a higher lipid oxidation by isolated hepatocytes (unchanged ketogenesis and oxygen consumption) or hepatic mitochondrial respiration but was rather associated with a rise in BAT uncoupling protein UCP1 (+25–28% vs standard).


Long term high saturated fat feeding led to increased "peripheral" fat storage and BAT thermogenesis but did not induce hepatic steatosis and NASH.

The full text paper is here