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Nutrition Past and Future

TPNS 52-54: The Best Low Carb Research (Money Can Buy)

Primitive Nutrition 52:
The Best Low Carb Research (Money Can Buy), Part I


So far I've tried to show you how little sense low carb diets make by looking at basic metabolism, evolutionary history, and dozens of human and animal studies.  You may have your doubts about my views, though, because you've heard of studies showing that low carb can be good for you.  Therefore, in this section I'll take a look at some of those studies.  I selected these because I thought they were the best the low carbers had, most of them created by their top experts.  These studies are surprisingly easy to pull apart.  Let me show you how.

All internet meat promoters are familiar with the first and perhaps the most interesting low carb study.  An arctic explorer named Vilhjalmur Stefansson became convinced of the superiority of an all-flesh diet after years of interaction with Eskimos.

As you can see in this article from Time Magazine from 1930, he and his partner Karsten Anderson consented to be observed by doctors for over a year as they ate an all-flesh diet.  I use the word "flesh" in the interest of accuracy.  You'll see why soon.  Stefansson had some radical beliefs about nutrition.  "Eating vegetables and fruits is just like a form of religion," he said. 

Here's the study their year of flesh-eating produced.  You will notice that it was funded in part by the Institute of American Meat Packers.  This is where I get the second half of the title of this section.  I set out only to find the best low carb studies.  But over time I couldn't help but notice that a pattern emerged.  The funding for many of these studies came from organizations with a financial interest in meat.  Go figure.

Search for diet studies funded by these special interest groups and you will see this pattern for yourself.  I'm not complaining.  I know this is how the world works.  But we should factor this into our interpretations when we read these studies.

A recent report found that the American meat industry is funding pro-low-carb studies in Sweden now, just as they did in 1929 with Stefansson.  Until I see a study funded by the meat industry telling us meat can be unhealthy I will consider their studies suspect on this basis alone.  But this is far from the only interesting feature of this old experiment.  Let's look at the details.

We are told that the resolutely meaty Stefansson had required occasional catharsis for moderate constipation before the experiment but we are not informed of the chosen remedy, which I'll guess was probably castor oil.  Maybe if he had a better attitude toward vegetables he wouldn't have needed catharsis.  For all the muscles he ate, his own muscles were called soft and flabby.  The experiment began with more meat and less fat than he cared for, resulting in nausea and diarrhea followed by what must have been a very uncomfortable ten days without a bowel movement. 

He quickly had another bout of digestive drama which required more tinkering with the fat to meat ratio.  He had more trouble again within a month due to eating spoiled meat, experiencing abdominal pain, nausea, and vomiting, although he fared better than a friend who ate with him.

His partner Karsten Anderson came down with pneumonia at the end of the all-flesh diet experiment.  For his recovery he didn't mess around, taking in plenty of carbs.  Both before and after the experiment he freely chose a mixed diet.

Anderson had the usual loss of appetite on his flesh diet which is to be recognized as sign of good health according to low carbers.

During the experiment both men were sedentary.

This separate paper from this experiment is very interesting.  Low carbers, take note.  After a year on an all-flesh diet, with presumably only carbs in the form of muscle glycogen in meat, both men showed impaired glucose tolerance.  Anderson actually had glycosuria.

If you don't know what that is, it's sugar in the urine, which is a serious problem normally associated with untreated diabetes.

Just as interesting, after going back to a mixed diet their sugar metabolism normalized.  Carbs cured them!

The top line shows you Anderson’s blood sugar after the all-flesh diet and the bottom shows the improvement he experienced once back on carbs. 

Look at the effects of this diet on these men. The acidity of their urine multiplied by two or three times.  This is also something seen in diabetics.  I'm thinking most low-carbers aren't aware of these findings.  If they were they wouldn't keep referring to this experiment.

It's not at all surprising that their high-saturated fat diet caused insulin resistance.  This can happen in mice even without weight gain.

Glucose intolerance was also observed in the sort of low carbers who inspired Stefansson as well.  In 1936, it was written that Eskimos have higher blood sugar than other people as a rule, and were considered glucose intolerant.

An amazing 44% of young Eskimos ages 15 to 29 indicated glucose intolerance in 1968.  Maybe Neal Barnard is on to something.

Despite this unusual and alarming result, the meat-industry-sponsored researchers reported no ill-effects.

After the Stefansson study was published, a doctor named Newburgh at the University of Michigan took exception to the message this study sent.  He quibbled with their descriptive title, "all-meat diet."  This is why I have used the phrase "all-flesh diet."  As we saw from Stefansson's distress at the beginning of the study, the diet was not so much high in meat but high in animal fat.  Newburgh said this was the only way their so-called "all-meat diet" could be made to work.  In his research he found kidney damage resulted from a diet of 32% lean meat.  You may recall from the Protein Choices section that 32% protein is in line with Paleo recommendations.

He found bias in the reporting of the researchers who conducted the all-flesh experiment, who said that in a prior study of 142 Eskimos, renal damage was rare.  Newburgh corrected them, pointing out that the study actually found that 14.5% had some form of kidney disease.  Even back then, it was clear to someone this study wreaked of bias.

Let's look at more recent studies.  This analysis of 21 epidemiological studies declared that there is no evidence that dietary saturated fat is associated with heart disease, as though there had been no other evidence worth considering from the last hundred years beyond these 21 studies. 

This was greeted as a vindication of saturated fat by the low carbers, who seemed to think the medical world would just accept this conclusion without skepticism.

As you might expect, these researchers had funding sources that might strain their capacity for objectivity.  Ronald Krauss, for example, has received funding from the National Dairy Council, the National Cattleman's Beef Association, and the Atkins Foundation.

Krauss only wants you to consume 35 to 40 percent of your calories from carbs, far below the recommendations of most experts.  You can see he, like many others, has uncritically accepted the belief that Eskimos are models of health eating their traditional blubbery diets.  You know more about that now than this expert does.  He also does not shy away from his relationship with the Dairy Council.

This study caused a fuss when it was released and was quickly discredited.

Jeremiah Stamler, the famous cardiologist, was disturbed by it.  He found it had numerous technical flaws, which you can read in this article.  If you do, it will be clear to you that at the age of 90, Stamler was still on his game.

Letters of complaint were sent to the publishing journal.  One concern was that the authors did not distinguish between carbohydrates of different quality.  That's a common low-carb sleight of hand that was caught this time by these letter writers.

If you replace saturated fats with junky refined carbs, heart disease will be a bigger problem.  Replace saturated fats with healthy carbs and heart health will improve.

There is no contradiction in this.  Researchers are perfectly able to see both junky carbs and saturated fat as unhealthy at the same time.

One of the authors of this controversial study knows the difference.  He said that a singular focus on saturated fat was unhelpful because I guess he thinks people will inevitably just replace them with bad carbs.  This is an interesting statement coming from the author of a study that focused singularly on saturated fat in order to contradict most previous research on the subject.  Remember, the study said there is no significant evidence linking saturated fat with heart disease.  How is this not misleading?

In fairness, these researchers did address what the saturated fat might be replaced by in a separate article, but this one has gone unnoticed by the low carbers.  Here they only distinguished between different types of fat, though.  I'm always amazed at professional health researchers who find the differences in fats to be extremely important, but make no mention of the differences in carbs.  Read this and you might put all carbs in the same category, from quinoa to candy canes.

You'll see this isn't the only low-carb-friendly study to hope you don't know the difference.  More studies are ahead in Part II.


Primitive Nutrition 53:
The Best Low Carb Research (Money Can Buy), Part II


Of all the low carb studies I’ve seen, this is the one I found to be the most perplexing.  Before I saw it I thought there would never be a study showing that atherosclerosis can be healed on a low-carb diet. I thought, until the low carbers produce a study of their own like Dean Ornish’s, documenting a regression of heart disease, there really isn’t much to debate when it comes to diet and heart health.  But here it was, a low-carb study showing a reversal of atherosclerosis.  This looks like a serious two-year-long study with real results.  Had I been wrong about nutrition all along?  Could a diet high in saturated fat actually make our arteries healthier? I came to believe a nutrient dense vegan diet is the best we can do, and that a meat-based low-carb approach is a disaster, through what I believed was a rational and skeptical process. 

But if I am a true skeptic, I am obligated to discard that belief in veganism’s superiority, as much as I love veganism, if it is shown to be wrong.  Would this be the study that would finally puncture my convictions? An early warning flag was raised for me because the funders of this one included the Atkins foundation.  It bears repeating: I sought out the best low carb studies.  I did not try to find the ones with questionable funding sources.  It just happened this way.  The funding doesn’t discredit their findings automatically.  Maybe the Atkins people had finally found a way to make their approach withstand scrutiny.  What did they come up with? This study compared three diets: low fat, Mediterranean, and low carb.  All the diets seemed to turn back atherosclerosis for these people.  Maybe these were fair-minded researchers.  Somehow the Mediterranean diet was the one that was highest in fiber, which should tell you all you need to know about the quality of carbs consumed on the low fat diet. But still, the walls of the arteries of the low carb group seemed to heal, just in like the other groups.  What happened here?

This same group of researchers published a study comparing the same people while on these same three diets in a paper published earlier on the topic of weight loss.  This prior paper got some interesting feedback, as some strange things were noticed in that one, too.  Some people gained weight despite reporting serious reductions in their calories.  The diets were not really reflective of the names they were given.  The low fat group didn't actually reduce their fat intake.  They just were not low fat.  Dean Ornish noticed the strangest quirk.  The Atkins diet group was instructed to choose vegetarian sources of fat and protein.  He asks the right question: Why were they told to do this?  Are the Atkins people advocates for vegetarianism now?

Here you see it for yourself.  ”Participants were counseled to choose vegetarian sources.”  Is this approach typical for low carbers? 

The lead authors responded to these comments.  They said the low fiber intakes were due to the lowered amount of calories they ate.  This, they said, is obvious, although I'm not sure why.  Unless these obese people had been super health-conscious vegans, which I would submit is impossible, I think it would be very easy to increase their fiber and decrease their calories at the same time.  They didn't really answer Ornish's question about vegetarian proteins other than to say that the Atkins diet they used was based on an Atkins book.   The low carbers were reported to be consuming only about 1250 calories, which is really low.  This is another problem.  The researchers were, in fact, leveraging the power of calorie restriction more for low-carb to help it look better.

Here's something the letter writers didn't notice.  I hope you can follow me on this one.  This is the breakdown of the patient population.  The patients were categorized by how thick their artery walls were.  The thicker they were, the more atherosclerosis they had.  There were big differences between these groups, with the highest tertile really standing out as having the most plaque.  Look how the groups were put together.  The low carb group had the lowest fraction in the lowest tertile, only 20%.  They also had the highest proportion in the highest tertile.  Even though the low carbers made up only 26% of the study population, they had 32% of the group with the most arterial plaque.  The low carbers started out with more plaque than the other groups.  This is important.

People with the thickest artery walls respond the fastest to healthy lifestyle changes.  It's sort of like how an obese person can lose more weight faster than someone who is just a little overweight.  I will never win a weight loss contest because I don’t have much fat.  It works the same way for atherosclerotic plaque.  If you are judging by the amount of plaque you regress, then having more people with the thickest plaque concentrated in the low carb group will skew the results.

The people studied in these papers also had a mean BMI of over 30, which is technically obese.  Cutting these people down to under 1300 calories a day is bound to make a big difference.  There is no way they got to be obese eating so few calories.  This was yet another study of calorie restriction, not low carb.  Look at calorie restriction in low-carb this way.  Saturated fat hurts your arteries.  If you eat less of it, there is less of it in you where it can hurt you.  Even if you are still eating a high proportion of saturated fat, reducing the total amount you eat will still give your body a chance to heal itself at least a little bit.

I'll remind you that our potato guy, although he didn't have his artery walls measured, did see big improvements in other tests without drastically cutting calories.  I think we can conclude from this study that to make low carb appear to make you healthier, you have to cut back severely on calories.

Dean Ornish also regressed heart disease, but his patients were consuming almost 600 calories more per day than people were in this Atkins-funded study.  I'd think getting to eat those extra calories would make a diet a lot easier to stick with over the long term.  Also, Ornish's study did not look at artery wall thickness only.  He also looked at cardiac events, and that's what counts.

You would think that a reduction in the thickness of artery walls will always translate into a reduction in cardiovascular risk, but that isn’t necessarily true.  It is clear that a regression or halting of atherosclerosis by itself does not reduce cardiovascular events when drugs are involved. 

This leads to the next point.  Ornish did not put his experimental group on cholesterol-lowering drugs.

The Atkins study did.  26% were on such drugs, and another 31% were on blood pressure medication.

It's quite possible the atherosclerosis in these people regressed as a result of their lowered blood pressure, both from the drugs and the weight loss.  This could be an important factor in this study.

While measurements of artery walls are surely valuable, other measurements are more important.  Here aortic valve calcification is seen as more important than such measurements...

And this calcification is strongly related to LDL bad cholesterol.  The authors don't tell us what happened to their LDL.  You know why.  LDL is the Achilles heel of low carb.  You can bet they would have told us if it improved.

Based on all these issues – inaccurately named dietary interventions, questions about the accuracy of the reporting of calories, vegetarian sources of protein for the low carbers, aggressive calorie restriction, confounding medications, non-random distribution of the patient population, and a lack of disclosure about LDL – this study cannot be the one to tell us low carb can be made more heart-friendly.  Scratch its surface a bit and this very impressive-looking study just turns out to more of the same old low-carb chicanery.

Our next study is brought to us by top low carb researcher Eric Westman.  Here he is telling us that in his study, he happened to find that an extreme ketogenic diet was better than a low-glycemic index diet for glycemic control in diabetics.  We've seen already that ketogenic diets are probably harmful to blood sugar regulation, and we've seen how other low carbers only want to compare their diets to junk-carb-based diets, so this one looks to be different and promising.

What's more, Westman said in 2007 that he takes no funding from the National Cattleman's Beef Association.  Maybe he's even free of special interest influence.

Or maybe not.  A year later you can see he did receive compensation from this group for speaking and consulting.  This is the same year that he created the study we're examining.

This study, you might guess, was funded by Atkins.  He assures us that the Atkins people had no influence over this study.  That's hard to believe since he is Atkins people.  Here you see he participated in a low-carb podcast to promote his new Atkins diet book.

Do some searching on Google and you'll see that Westman has a great relationship with Atkins, who have funded numerous studies of his. 

This study has the usual dead giveaways of low-carb bias.  No mention of LDL cholesterol.  No mention of fiber consumption.  No mention of sugar intake.  From this, I’ll assume LDL went up for the low carbers, and that the carbs in the low-GI group included plenty of junk.

But there is a more interesting and subtle sign of bias in the subjects they used in the study.  First, look at those BMI's.  All are over 37. That is far into obese territory.  Do these people represent you well?  If not, maybe this study can’t tell you much about what is best for you.  More interesting, and I must say, highly unusual, is the nonrandom assignment of participants by race.  The low-glycemic group had a significantly greater proportion of African Americans.  They also have a higher percentage of women.

African American women are not the same as caucasian women.  They tend to gain more weight on the same number of calories.  Moreover, they may be more susceptible to insulin resistance and diabetes.  Remember, this is a study of glycemic control in diabetics, so this tendency for differences in blood sugar regulation is important here.  Why weren't these subjects properly randomized?  This is pretty sly, don't you think?  These Atkins people know all the tricks.

What exactly was the low-GI diet they used?  We are told it was based on what Westman calls a lay-press book.

This is the author of that book.  His name is Rick Gallop.  He is not a fan of the Atkins diet. Maybe comments like this inspired Westman's study, giving him a little bit of payback.  He wants us to keep our calories and fats low, especially saturated fat.  This is very mainstream and responsible advice.

Amazingly, we can see at the bottom that the obese people in the  low-GI group did not lower their fat intake by even a single percentage point on the diet that was supposedly based on Mr Gallop’s book. They actually ate fewer carbs than before. It seems to me this study is pretty useless as a representation of Gallop's ideas.

The first paragraph is good for a laugh.  Westman says there was no difference between the two groups in terms of adverse effects.  Then look at the symptoms.  I see the low-carb group as worse off in every way but back pain.  Really?  Back pain?  Dr Westman is really working hard in this one to make Atkins look good.  No wonder they keep funding him.

Look at that list of adverse effects and you will know what conclusions I draw from this.  Under controlled conditions and administered by a top low-carb promoter, a ketogenic diet will induce headache and constipation in more than half of people, with large percentages also experiencing diarrhea and insomnia.  It was, however, better for glycemic control than an unhealthy diet they just made up and called low GI.  That is not what I would call a success.

Stay tuned for Part III, where I'll show you what the top low-carb all-stars have created when they put their heads together.  Nothing but the best of low-carb for you in the Primitive Nutrition Series.


Primitive Nutrition 54:
The Best Low Carb Research (Money Can Buy), Part III


Now for the first of two studies conducted by some familiar names to low carbers.  I'll call these guys the Low Carb All Stars.  The names I recognize here are Jeff Volek, Stephen Phinney and Richard Feinman.  I'll focus on Phinney separately in the next section because he’s so interesting to me.

Maybe, just maybe, Volek and Phinney have a possible bias toward low carb. 

You can see Volek, like Westman, has been a reliable long-term partner for the Atkins people.  That’s no problem, of course, but it’s just good to bear in mind.

By now I hope you know the drill. I'm not even going to bother to read the text.  Let's just look at the data.  Here's an accounting of what the two groups ate.  The low carb group is CRD and the low fat group is LFD.  The participants were obese here, too, with BMI's well over 30.  We might assume from this that these people were not eating the best diets coming in to the study, and indeed, they entered eating only 13 and 16 grams of fiber daily, as you see in the last line.  The low fat group only managed to add one extra gram of fiber to that pitiful amount on the diet the All-Stars devised for them.

To put that in perspective, this is the nutrition data for a cup of lentils.  You would get 16 grams of fiber from only 230 calories. That means this one serving would represent nearly all the fiber they ate in a day.  Can you imagine how many advanced degrees these guys must have between them?

You'd think they'd know enough about nutrition to at least have their low fat diet meet the minimum recommended intake of fruits and vegetables.  For their participants, the CDC would say they would have needed 1.5 cups of fruit and 2.5 cups of vegetables.

I picked some standard produce items to fulfill that amount and I wound up with 36 grams of fiber, or more than twice what the all-stars gave them.  They should have eaten more fiber with the rest of their diet, including whole grains and beans.  Instead, it is clear that most of their carbs were junky carbs.  They fed them this way to guarantee that their low carb diet would look good by comparison.  They think you'll assume a carb is a carb is a carb, and stop thinking there.

In this study they want you to be impressed with the effects each diet had on triglycerides...

as well as lipoprotein particle size, which they broke down in detail.  In my Anything but LDL section I already explained the possible shortcomings of these biomarkers.  Look at this table, with all it's thoroughness, and ask yourself if these guys really don't know any better about fiber.  Amidst all their numbers, the one line that matters the most is the LDL score, and it went up despite the 800 fewer calories the low carbers were eating per day.  Once again, low carb is much, much worse than an all-potato diet. Don't let this blizzard of numbers distract you from that.

These guys should know that low fat diets don't necessarily promote the small, dense LDL particles they are so concerned about.

And remember that fasting can improve the lipoprotein subclasses as well.  With such a reduction in calories, you would expect that these biomarkers would improve a bit regardless of the diet.  Once again, a calorie restriction study is masquerading as a low carb study.

Plant foods can improve these lipoprotein subclasses, but there is a catch.  You'll need to eat more than 17 grams of fiber per day.

I'll make even faster work of this one from the Low Carb All-Stars.  It's an analysis of different low carb studies.  Here you see the studies listed which they picked to bolster their low-carb beliefs.  I think you can assume the low fat diets in these studies were not based on fresh, high fiber, whole plant foods.  Nevertheless, compare the two basic diet approaches for LDL.  Low fat dropped it by quite a lot in some cases.  In the low carb studies, no studies showed an improvement in LDL despite very low calorie intake.  None.  They managed to break even in two.  Once again, a very poor showing given the importance of LDL.

This is a consistent pattern for low carb.

Children put on ketogenic diets experience the same thing.

Unfortunately some of these kids have elevated LDL bad cholesterol for years after stopping these diets.  Some of these children actually had total cholesterol over 200.  Pause this and read that last paragraph.  It's really clear what these diets do to your cholesterol unless you are severely restricting calories.

Plant-based diets, however, can dramatically lower LDL.  This is the biggest problem for the low carbers.  Almost any diet that a health professional might recommend looks better by comparison.

Stephen Phinney was an author in each of the two studies, but I think he warrants videos all his own.  He's up next in the Primitive Nutrition Series.

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