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Comment by lngnmn | Hacker News Reader

It obviously does not because there are whole populations, such as Tibetans, who consume butter on daily basis and are still alive and well, without any cardiovascular epidemic.

What is a risk, by the way? How it is defined, apart from a personal lifestyle, diet, habits, current set of disorders and chronic illnesses of a particular person? It is a likelihood? An average of some imagined population of which some non-representative sample is treated according to some abstract, disconnected from reality model of a few selected unproven factors in a complex multiple causation individual phenomena? How the value of that number related to anything meaningful? It passes peer-reviews because it conforms to a socially constructed consensus (the current set of memes) but no one does a review of logic and causality.

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The classic example, since modern nutrition research started in the '50s, is Inuit/Eskimo. They eat a lot of whale blubber, yet have very low rates of heart disease.

A good book that presents the case against nutrition research is "The Big Fat Surprise: Why Butter, Meat & Cheese Belong in a Healthy Diet."

I wonder if the Tibetans and Inuits benefit from the fact that their dietary fats come from animals who lived healthy, whole lives. Much of the US consumes dairy and meat that comes from animals who were shoved into dark, overcrowded, stressful, unnatural habitat and fed strange feed that they'd normally not eat such as corn and grain.

To argue that, you'd have to demonstrate that the fats in animals raised on what you call healthy food differ chemically from the fats you'd find in animals fed otherwise.

Related example: The glucose from sugar beets is chemically identical to and indistinguishable from the glucose from sugar cane or corn. Animal fat tends to be a more complex mix, but while no expert I suspect there's only so many different lipid compounds produced and stored in animal cells. After all, the energy currency in any animal's bloodstream is mainly glucose - the source information is lost.

There are excellent _ethical_ reasons not to mistreat animals as is today often the case. I'm not sure that there are chemical reasons related to nutrition.

Yes there is some evidence for that. In particular grass fed beef vs grain fed beef:

http://www.theglobeandmail.com/life/health-and-fitness/healt...

Most claims, however, focus on omega-3 fats, in particular alpha linolenic acid (ALA). Higher intakes of this plant-based omega-3 fatty acid are associated with a lower risk of heart disease, stroke, Type 2 diabetes and depression.

According to Dr. Richard Bazinet, a professor in the department of nutritional sciences at the University of Toronto who analyzes fatty acids in beef, grass-fed beef outranks grain-fed beef when it comes to ALA.

Conventional beef has about 20 milligrams of ALA in three ounces, whereas the same amount of grass-fed beef has 50 to 100 mg. A big difference? Yes. Meaningful? That depends.

Women need 1,100 mg of ALA each day; men require 1,600 mg. Eating a six-ounce grass-fed steak three times a week provides, at most, 5 per cent to 8 per cent of your daily ALA requirement. Keep in mind that during cooking, the ALA content of meat will decrease since ALA is found in fat.

Making the switch to other grass-fed animal foods, such as pasture-raised poultry and eggs and grass-fed dairy, could conceivably make an appreciable difference towards your daily ALA needs.

  glucose from sugar cane or corn

Is there meaningful mass production of glucose (or dextrose) from corn? Corn syrup is higher in fructose, which is metabolized very differently from glucose.

Absolutely! The glucose mix initially produced from corn is about 50% glucose and 42% fructose, which is roughly the same ratio as you get from beets or cane. You can then _optionally_ raise the percentage of fructose to 55, 65 or even 90% fructose. The 90% stuff is usually diluted/mixed before use.

HFCS is just sugar syrup with an intentionally elevated level of fructose. There's nothing that specifically ties corn to high amounts of fructose, other than that corn is heavily subsidized in the US while other sources of sugar are hit with import tariffs. So corn is what US sugar producers will tend to use as a source.

I wouldn't say "The Big Fat Surprise" makes a case against nutrition research as a field - rather it points out some of the difficulties in performing nutrition research (the largest: it's almost impossible to enforce compliance with an experimental diet without massive expense) and some of the flaws in traditional conclusions (e.g. That dietary fat is associated with heart disease - turns out it probably isn't)

I do not think you can generalize from Tibetans or other populations. That is because those rural populations often have a much healthier diet than the standard american diet. More vegetables, more fiber, less animal products in general. To say that this obviously shows that butter cannot be that bad is just not true.

You are right in one point: If the only thing you eat is butter with your veggies then you do not have much of a problem in terms of a cardiovascular epidemic.

I think we focus on diet over environment too much. It isn't just what you eat but how you get around that is vital to tackling the cardiovascular epidemic.

The only evidence that I currently have available is the Netherlands. The only western country to have a reducing obesity index, by 2030, predicted to be 8.5% down from 10%. Their diet is a very typical western diet.

However their transport system and their urban planning is hugely focused on prioritising walking and cycling with good provision of local amenities within easy cycling distances. Yes, you build higher density urban environments, but this is a good thing.

In Netherlands it is common to have rather cold temperatures in houses even if people can afford to pay for warmth. And cold requires body to spend much more energy that is coming directly from burning body fat unless one shivering from cold.

In fact if one wants to loose like 10 kilos quickly, just climb to Everest. Most of that weight will be spent on body heating, not muscular work.

That also explains why butter does not harm people in Tibet. It is not stored as body fat and goes directly into body heat.

That's an interesting one I had not considered. Culturally living in a cold environment and not wrapping up warm will have an effect on calorie burn.

Do you have any references on that? I was under the impression being cold didn't really burn that many more calories. I'll stop wearing a jacket if I can burn hundreds of calories.

Sitting in a cold room burns an extra 50+ calories an hour if you are not dressed for it. That does add up, but is also unpleasant.

Just read hypothermics.com . Its author, Ray Cronise, has done a lot of measurements using proper equipment.

And anecdotaly I have a co-worker who was into serious climbing. Before a high climb like over 6km he on purpose typically gained like 5 kilos of weight and still came back learner from the trip. And he knows for sure that that was due to coldness as on much more physically demanding trips at warmer altitudes weight loss was much smaller.

My understanding is that you also burn more energy at altitude.

This has been given as one of the problems that Scott faced when man-hauling sledges on the Antarctic plateau at 3000m.

"Being cold" does not have any particular caloric advantage until and unless you are cold enough to shiver. Shivering, as it happens, is a fantastic way to burn calories, and 15 minutes of shivering is equivalent to approximately an hour's worth of exercise.

http://www.livestrong.com/article/317620-how-many-calories-a...

That link contradicts that?

"even mild cold that doesn't cause you to shiver starts to burn through those brown fat stores, jumpstarting your caloric burn rate."

Famously, Inuit team drivers for Arctic expeditions would eat all the butter out of the food supplies first.

Indeed. Thanks for the correction. The science, as I understand it, is that just being cold, but not to the point of shivering, will help boost your metabolism if you're performing exercise, while just being cold while idle will burn a basically insignificant amount of calories.

Interesting. Is that on purpose, to help lose fat, or to get the body used naturally handling a wider range of temperatures (I've read yoga prescribes that to some extent), or something else?

You are right that being active is also very important for cardiovascular health. However, you cannot underestimate the importance of diet as it too is a daily reoccurent factor for health.

Agreed but when you look at the Dutch diet, it really is not good. I mean sprinkles on toast really is not food. However the assumption is that, you as a child, will get to school by walking or cycling and you will get around for most of your childhood independently by bicycle.

The Dutch are unusually active in general, and this may well be down to their environment encouraging being active from birth.

I'm not saying diet is not a factor (1 in 10 are obese), but, the UK is currently at 27% (1 in 4), the worst in Europe heading for 35% (1 in 3) obese by 2030 with a similar diet profile to the Dutch, indicating about 25% of obesity will be down to environment. The US is even worse. Both the US and UK have an extremely car dependent design philosophy. One that the US is rapidly tackling through road diets. However planning is still a step behind at the moment.

I'm not disputing diet is vital, but if you have to get into a car to do a 0-5 mile journey because the "roads are too dangerous to cycle" or you won't let your kids walk/cycle to school 2 miles away you end up with an obesity problem no matter how good the population's diet.

Actually the typical Tibetan diet is heavy on grain, meat and dairy.

Are tibetans generally heart-healthy, though? I took that for granted but did not actually fact check the original poster. I think he just wanted to give an example for a rural, healthy eating society. I do not know if that was true in the past or is now, though.

That's not at all obvious. Tibetans have a very different life style and nutrition than, for instance, westerners.

Which is irrelevant, as it only speaks of total risk. If butter was bad, it would be bad for them too, in a controlled study against not butter eating Tibetans, regardless if they all run 10k miles per day and eat only vegetables.

If the sample size was large enough and you could factor our everything else, then yes. I don't think anything like this was done, though.

What exactly is your point, then?

+1 Additionally, even if you could and would factor out everything else, "obvious" would hardly be the right word to use.

That the lifestyle difference is irrelevant since any study that measures the impact of a food in health should control for it.

It can't be controlled for if there is no variation in the population. At that point it becomes a fixed effect--a population-specific intercept, as it were--and the only way to net that out would be through a difference-in-difference type study.

>It can't be controlled for if there is no variation in the population.

You think there are no Tibetans who don't exercise much and don't eat much vegetables either?

Depends. The external validity may be questionable due to the height of the Tibetan plateau, epigenetic expression that is potentially common in the nation, or any number of other factors. In other words, conditional randomization is not true randomization required.

However, the grandparent comment I understood to be relevant to dietary factors.

This is a fault of journalism, not of epidemiology.

Studies very rarely go so far as to make any causative claims.

Knowing that those who meet condition A have a higher change of condition B is valuable, even if A and B are relatively unconnected.

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