Sunday, December 30, 2018

More evidence for Linoleic Acid and Autoimmune Diseases

"Mechanism behind omega-6 seed oil triggering autoimmune diseases"

Read the whole thing, in which linoleic-acid-derived HNE seems to create antibodies against DNA, of all things.

Welcome, Stan!

Saturday, December 8, 2018

Body Temperature in Athletes

Confirming some of Tim Noakes' work:

"When researchers later downloaded the data, the three women had peak temperatures during the race ranging from 105.4 to 106.7 degrees (40.8 to 41.5 C)—all higher than the 105 degree (40.5 C) threshold that’s considered a key diagnostic sign of exertional heat stroke. Yet they hadn’t collapsed. In fact, the team won a medal."

Read the whole thing: "How Elite Athletes Respond to Extreme Heat"

Worries about body temperature, especially in fever, are unjustified most of the time.

Tuesday, December 4, 2018

Mark Sisson on Kraft Heinz and Primal Kitchen

"I was adamant about maintaining product quality and integrity from the earliest of discussions with Kraft Heinz, and they were fully aligned with this from the beginning.... 
"If those ingredients change, you will stop buying. Business 101. 
"I know that. Kraft Heinz knows that.... 
"I think of all the people dousing the salad their doctor said they should start eating in soybean oil-based dressing and buying “olive oil mayo” that was mostly just seed oil, and it frustrates me. Imagine if they switched? Imagine if they all switched? Imagine if we were able to shift the collective omega-6:omega-3 ratio back toward ancestral optimums. Longtime readers know how big a change a person can make in his or her health just by changing the fats you eat. Now imagine a population doing it."
Amen. This is how it will happen.

Saturday, December 1, 2018

"NIH Seeks Feedback on Nutrition Research Plan"

They'd apparently stopped funding nutrition research, so this is a major development.

Link via Blog - The Nutrition Coalition

Saturday, November 3, 2018

Does Parkinson's Disease Start in the Gut?

Could be.

Fascinating post, especially the association between removal of the appendix and protection from Parkinson's.

Appendicitis was one of Burkitt's Diseases of Civilization...

Wednesday, October 31, 2018

"Don’t Think Too Hard About Your Running Form"

Absolutely right.

The most illuminating moment I had concerning running form was when I got lost on a trail run, and had to get back in the dark.

It turned out running in the dark was easier than walking, and the fact that I couldn't see what I was stepping on in my Vibram FiveFingers made it easier, not harder.

I realized my brain was just interfering with my body, like an annoying backseat driver.

One it was forced by blindness to shut up, things went much more smoothly .

Wednesday, October 24, 2018

"New Hope for Diagnosis of Chronic Infections; and Ancestral Health (Paleo) Survey"

Could be really helpful. "...a new startup, Aperiomics, is offering tests that are capable of identifying 37,000 different infectious pathogens..."

Link via Perfect Health Diet

"#Paleo Survey 2018 – Paleo People, We Need Your Input"

This is a follow-up to a 2013 survey. Should be quick, from Robb Wolf.

Wednesday, October 17, 2018

Linoleic Acid and Asthma: Therapies

They never actually mention linoleic acid, but they do discuss lipid peroxidation and some of the products thereof, such as malondialdehyde, which are produced from LA.

"While the specific mechanisms underlying asthma have yet to be identified, there is accumulating evidence that oxidative stress from altered GSH/GSSG redox status may play an important role in the modulation and severity of the disorder."

So the molecular mechanism section is quite incomplete.

As such, it's an annoying article, as it is a  missed opportunity from a mechanistic perspective, many of which have been described under other contexts. It also does not discuss the similarities to atherosclerosis, which are pretty obvious when reading this paper.

But the therapeutic approaches are sound, and validate the underlying concept of omega-6 fat involvement in asthma.

"Glutathione Redox Control of Asthma: From Molecular Mechanisms to Therapeutic Opportunities"

Hat tip to Chris Masterjohn.

New from Japan: What They Don’t Tell You About Culture Shock

From Grace Under Pressure

"What They Don’t Tell You About Culture Shock"

Read the whole thing!

Thursday, October 11, 2018

"Fitness versus adiposity in cardiovascular disease risk"

"Having a low VO2max increased CVD mortality risk as much or more than traditional risk factors such as diabetes mellitus, high cholesterol levels, hyperension, or current cigarette smoking"

Wow.

New from Japan: Life Updates: I’m Back! (Hopefully)

From Grace Under Pressure

"Life Updates: I’m Back! (Hopefully)"

Read the whole thing!

Friday, October 5, 2018

"Muscle damage and inflammation biomarkers after two ultra-endurance mountain races..."

About what you'd expect: exercise is hard on the body.

Due to short follow-up, it doesn't look at how quickly these indicators return to normal, as other studies have.

Monday, October 1, 2018

Wednesday, September 19, 2018

"A Grand Unified Theory of Polyunsaturated Fatty Acid Misbehaviour in Inflammatory Disease"

LOL: "But another clue was supplied by Tucker Goodrich, the PUFA ninja..."

Very interesting piece, read the whole thing.

Link via The High-fat Hep C Diet

Wednesday, September 5, 2018

"The Pros & Cons of Hormone Replacement Therapy for Primal Women"

Interesting article, if you are in the market. Read now, don't wait!

Link via Mark's Daily Apple

"This New Research Can Help You Decide How Much to Lift"

A really great post on how to balance size vs. strength.

Link via Alex Hutchinson - Outside Online

Monday, August 20, 2018

Thursday, August 9, 2018

Tuesday, August 7, 2018

Review: Jane Brody of the "New York Times" on the Paleo Diet

Ms. Brody (I presume it's Ms., since she does work at the Times) is the Times' august "personal health columnist, a position she has held since 1976," and as such, one would think she'd be well-suited to examine the details of a diet.

So let us see what she has to say about my own personal diet.
"Is the Paleo Diet Right for You?"
"In the Paleo era, people ran around all day and rarely lived past 40, so their risk of developing the so-called diseases of civilization is unknown."
That's not even the article, it's just the starting blurb, which ought to entice us to read further, not induce wincing, as is the case here.
  1. "...people ran around all day..."
This no doubt refers to the debunked calories-in, calories-out model, oft summarized as "east less, move more".  We now know that human movement appears to be largely constant, and the fact that paleo man ran around more doesn't per se have an impact on their weight, obesity being the primary current manifestation of the Diseases of Civilization. See here:
"Energy expenditure and activity among Hadza hunter-gatherers." [1]
  1. "...rarely lived past 40..."
This is a familiar trope, and indicates that Ms. Brody does not understand arithmetic. Forty would represent (assuming her number is correct) an average, not a max lifespan for a paleolithic person.
"Life expectancy is an average, and it fluctuates with age as the risks we face change throughout our lifetimes. Both those facts make it a frequently misunderstood statistic. High infant-mortality rates depress the figure substantially. This can lead contemporary observers to the false conclusion that most humans died quite young, even in the not-so-distant past."
That's from this article, "Who Lives Longest?" that appeared in the NYT in 2013. It includes a discussion of paleolithic lifespans. The max was higher than 40. Ms. Brody should read it.
  1. "...their risk of developing the so-called disease of civilization is unknown..."
Hard to know, but not unknown. Paleopathology is the field of determining ancient health, and what it tells us is clear: the diseases of civilization appeared at the end of the Paleolithic, and people got sick, fast. From Jared Diamonds 1987 article, "The Worst Mistake in the History of the Human Race":
"Skeletons from Greece and Turkey show that the average height of hunter-gatherers toward the end of the ice ages was a generous 5' 9'' for men, 5' 5'' for women. With the adoption of agriculture, height crashed, and by 3000 B. C. had reached a low of only 5' 3'' for men, 5' for women. By classical times heights were very slowly on the rise again, but modern Greeks and Turks have still not regained the average height of their distant ancestors... 
"...Compared to the hunter-gatherers who preceded them, the farmers had a nearly 50 per cent increase in enamel defects indicative of malnutrition, a fourfold increase in iron-deficiency anemia (evidenced by a bone condition called porotic hyperostosis), a theefold rise in bone lesions reflecting infectious disease in general, and an increase in degenerative conditions of the spine, probably reflecting a lot of hard physical labor. "Life expectancy at birth in the pre-agricultural community was about twenty-six years," says Armelagos, "but in the post-agricultural community it was nineteen years. So these episodes of nutritional stress and infectious disease were seriously affecting their ability to survive.""
I haven't even gotten out of the blurb yet, and we've discovered 81% of the words in the blurb are untrue or at least grossly questionable statements.

Welcome to the New York Times! And thus you see the problem with fake news. It takes me 469 words to debunk 21 bogus ones.

The article doesn't get any better from there, but having demonstrated the general tone (most of these points are repeated in the body) I'll just hit a couple of high points.

Ms. Brody observes:
"There have been no studies of large groups of people who have followed the currently popular versions of the Paleo diet for decades to assess their long-term health effects."
This is a nonsensical criticism, as there are no such long-term studies of ANY DIETS for their health effects, with the exception of the Dietary Guidelines we are all forced to follow. The Dietary Guidelines failed to show any benefits for the health problems they were purported to ameliorate. The few paleo diet studies (as she mentions at the very end) have shown greater benefits than almost every other diet studied, including the ability to reverse many of the diseases of civilization.
"Several short-term studies among small groups of people (often with no control groups) suggest that the Paleo diet is more effective than the Mediterranean approach..."
She nevertheless endorses the Mediterranean diet, while ignoring the fact that it also has no studies to assess its long-term health effects. Note the double standard.

She seems to be using the Paleo Diet as espoused by Loren Cordain, which is fine, although not my personal choice. It's rather odd that she doesn't look into other versions of the paleo diet, which address some of her criticisms. Some of them are fair, but couched in language that demonstrates a lack of basic knowledge of food and physiology. No, dairy is not a great source of Vitamin D, Ms. Brody, the sun is. "There is no such thing as “a” Paleo diet" she says. Which is true, and every single paleo diet book tells you that. It's a strawman argument, and could have been rectified in a few moments online.

She does go talk to one "expert", Dr. Marlene Zuk, who wrote a book called Paleofantasy [2], from which Ms. Brody apparently got the substance of her article. Dr. Zuk is an evolutionary biologist, but she studies insects, not people. Hence she's not familiar with the subject she criticizes. But don't take my word for it, here's a review, from the academic journal Evolutionary Psychology: "Throwing Out the Mismatch Baby with the Paleo-Bathwater" [3]:
"In sum, Zuk has written a wide-ranging, accessible, and stimulating book, but one that mainly triumphs in dispatching paleo-hucksters, anonymous bloggers, and scholarly straw men. In failing to acknowledge the successes of the mismatch perspective, Zuk has reached the wrong conclusion: The mismatch perspective has not been a failure; it has been tremendously fruitful."
Now what you need to understand is that Dr. Zuk's book was published in 2012, and Ms. Brody's NYT article was published on August 6, 2018. So it's six years out of date.

In the interim Prof. Daniel Lieberman, Chairman of the Department of Human Evolutionary Biology at Harvard wrote the masterful The Story of the Human Body: Evolution, Health, and Disease [4]. If there hadn't been a paleo diet already, this book would have spurred it. And if Ms. Brody had based her criticism on the paleo diet on that book, she might have realized there is much less to criticize. (Prof. Lieberman is not a fan of the paleo diet per se, but cites some of the early papers from the founders, and makes the same argument.)

What's entirely missing, of course, is any defense of the paleo diet from a supporter.

So the Times turns out to be not even news, just fake; simple fear, uncertainty, and doubt. This article is basically a tarted-up book review of a book six years old combined with a snarl.




[1] Pontzer, H. , Raichlen, D. A., Wood, B. M., Emery Thompson, M. , Racette, S. B., Mabulla, A. Z. and Marlowe, F. W. (2015), Energy expenditure and activity among Hadza hunter‐gatherers. Am. J. Hum. Biol., 27: 628-637. doi:10.1002/ajhb.22711

[2] Paleofantasy: What Evolution Really Tells Us about Sex, Diet,and How We Live. W. W. Norton & Company: NY. 2013. 255 pp., ISBN #978- 0393081374 (hardcover).

[3]  Robert O. Deaner and Benjamin M. Winegard; 2013; Book Review: Throwing Out the Mismatch Baby with the Paleo-Bathwater; Evolutionary Psychology; doi: 10.1177/147470491301100123

[4] The Story of the Human Body: Evolution, Health & Disease By Daniel Lieberman
Publishers: Pantheon Books, Random House, USA (2013) and Allen Lane (UK) 2013 ISBN: 978-1-846-14393-9

Thursday, July 12, 2018

Review: "Fitness Confidential" by Vinnie Tortorich

tl;dr: Recommended, fun and useful account of a top trainer. 
(The links on this page help support the blog!)

For those of us who participate in the health and fitness worlds in podcasts or twitter, Vinnie Tortorich has been a fixture for many years.

Vinnie is "Hollywood's go-to guy for celebrities and athletes looking to get fit fast." He's a "trainer", the guy you go to to lose some pounds and tone up before your next movie role, or for the rest of us, before summer arrives.

Formerly known as "America's Angriest Trainer", (he doesn't really push that line anymore) Vinnie seems to have mellowed in recent years, but you'll still get some of his attitude in this book, originally published in 2013. (You can see him in the photo on the cover, although it's unclear if he's angry about the dietary idiocy foisted on Americans, angry about a client not listening, or just in agony while on an ultra-length bicycle ride.)

Argh!
What you get in this book is Vinnie's biography, essentially, peppered with mostly anonymous stories of his experiences in his own life that shaped his approach to training people. Despite the subtitled tease "get the dirt", one of the things you won't find in this book is dirt on clients. Vinnie doesn't kiss and tell and name names, although there are a few names mentioned. Interestingly, one of the non-anonymous clients Vinnie discusses is his co-author, Dean Lorey, who fired Vinnie initially after finding his approach challenging.

Lorey came around, wound up thin and running a half-marathon, and then proceeded to nag and coach a reluctant Vinnie into writing this book together.

The result is a well-written and quick read. You won't find pages of recipes or workout routines, instead you'll find concise principles that (in my experience, independent of Vinnie) will work, and lots of entertaining stories to illustrate the principles and drive them home.

Of more value is Vinnie's advice on how to select a gym, and trainer, some real useful thoughts about what works and what doesn't, and tips on how to help people get motivated. Some of it is quite counter-intuitive.

I read this book on a flight from LA to NYC, and it kept pulling me along.

The surprising thing about this book, perhaps, is that he's not an angry guy, he's caring and thoughtful, and seems to be motivated to continue his career by a genuine desire to help people, both his clients and the rest of us.

N.B. When you reach the advertised "end" of the book, keep reading. The best part, I thought, was in the chapters after the story of the training and diet stuff is over. This is the story of Vinnie's battle with leukemia and his fight to conquer a 509.5-mile bicycle race through Death Valley. It's the best part of the book, in my opinion, and is not to be missed.

Overall, it's highly recommended. If you're looking for a simple and straightforward recipe for weight loss and fitness, this is a fun and entertaining way to get it, and you'll wind up with a better approach than most PhDs.

FITNESS CONFIDENTIAL: Adventures in the Weight-Loss Game

Thursday, June 28, 2018

What's Worse—Carbs or Seed Oils? Understanding a High-PUFA Diet.

tl;dr: The one study I'm aware of that shows conclusively that excess glucose acts as an accelerant for excess n-6, but it not nearly so harmful without the n-6, in vivo.

This post has been moved to Substack. Please follow me there for more content like this!

Wednesday, June 13, 2018

Wednesday, June 6, 2018

Thoughts on "Cardiolipin Synthesis in Brown and Beige Fat Mitochondria Is Essential for Systemic Energy Homeostasis"

Interesting confirmation of a core mitochondrial functional role for cardiolipin, and some interesting observations about cold-adaptation.

Get used to shivering! 
"However, the ability of adipose tissue to expend energy is a dynamic process that continues to increase with prolonged cold exposure, only reaching maximal capacity after several weeks (Cannon and Nedergaard, 2004)."
And clearly staying warm is overwhelmingly dependent on fat metabolism.
"However, the enrichment of lipid metabolism proteins far eclipsed that of proteins involved in all other metabolite pathways from 3 days to 3 weeks of cold exposure (Figure 1B)."
This likely explains why overweight people or inactive people have such a problem staying warm. Fat-burning capacity is dependent on stimulus, and while this doesn't show it, it likely atrophies like every other function of the body. Use it or lose it.

One of the key questions around cardiolipin and omega-6 fat intake is: what is a cardiolipin supposed to look like? This is more evidence that they're not supposed to be saturated with linoleic acid, leaving them uniquely susceptible to oxidizing and producing toxins like HNE as they damage mitocondrial function.
"Newly synthesized CL is characterized by shorter, more saturated acyl chains, which can be remodeled by phospholipases, and acyltransferases through monolysocardiolipin (monolysoCL) intermediates to generate a diverse pool of CLs."
It shouldn't surprise that CL is produced in an ideal state. Why it so readily takes up linoleic acid is an interesting question...

The paper also claims that energy production in brown-fat adipocytes (fat cells) controls systemic glucose homeostasis and therefore type 2 diabetes.

I'm a little more skeptical of that claim, as I looked into the connection between mitochondrial dysfunction and diabetes, and it's not as clear as I would like it to be. If this was a clear mechanism, then it would suggest that people living in warm climates that never experience a need for cold thermogenesis would be more susceptible to diabetes, and we really don't see that.

They get it when the industrial diet is introduced, same as everyone else on the planet.

Friday, April 27, 2018

LDL Cholesterol: You Aren't Always What You Eat, or Roundabout Ways to Improve Your Diet

Sometimes you read these papers and shake your head.

"Lowering Dietary Saturated Fat and Total Fat Reduces the Oxidative Susceptibility of LDL in Healthy Men and Women"

The troll who pointed me to this was trying to argue that this invalidated the claim that omega-6 polyunsaturated (n-6) fats are important in cardiovascular disease (I gather), since lowering saturated fat (see the title) lowered oxidation.

Oddly enough, he was almost right, but not quite.

Fat components
The intervention was to have fixed protein (15%), but a variable rate of saturated fat (SFA), to be replaced by carbohydrate (CHO), and fixed rates of monounsaturated and polyunsaturated fats (MUFA and PUFA, respectively). And they did a good job of detailing what the diet included, right down to the individual fats.

However you have to go to a different study to find all the details ("Effects of Reducing Dietary Saturated Fatty Acids on Plasma Lipids and Lipoproteins in Healthy Subjects")

To sum the variation, SFAs were 16%, 9%, and 5%; and CHO was therefore 48%, 55%, and 59%. MUFA was 14%, and PUFA was 7%.

The diet part of it seems to have been very well done, indeed. If you want some idea from where the food may have come, may I introduce you to their sponsors?
"The DELTA Investigators express thanks to the following contributors: AARHUS, Bertolli, USA., Best Foods, Campbell Soup Company, Del Monte Foods, General Mills, Hershey Foods Corp., Institute of Edible Oils and Shortenings, Kraft General Foods, Land O'Lakes, McCormick Incorporated, Nabisco Foods Group, Neomonde Baking Company, Palm Oil Research Institute, Park Corporation, Procter & Gamble, Quaker Oats, Ross Products Division/Abbott Laboratories, Swift-Armour and Eckrick, Van Den Bergh Foods, Cholestech, Lifelines Technology Incorporated."
Wow.

The troll was almost right because LDL oxidation did indeed go down in this study. But it went down for a reason that I wouldn't have expected, and which leaves me somewhat perplexed to explain mechanistically. 

The paper goes on ad nauseum along these lines:
"Convincing evidence suggests that oxidative modification of LDL plays an important role in the pathophysiology of atherogenesis (Steinberg 1997). In recent years, numerous molecular mechanisms have been proposed to explain the different oxidation pathways that lead to modification of LDL (Steinberg 1997). 
"One of the earliest steps in the generation of oxidatively modified LDL is the peroxidation of its polyunsaturated fatty acids (PUFA).3 The oxidative breakdown products of these fatty acids, such as malondialdehyde [MDA] and 4-hydroxynonenal [HNE], form covalent bonds with apolipoprotein B (apo B)..."
Yeah, yeah. Old news (the paper is from 2000), but here's where it gets odd:
"The results of the present study also show that LDL composition (LDL quality) affects susceptibility to oxidation. [It] was inversely correlated with the quantity of LDL oleic acid (r = −0.29, P < 0.01), and positively correlated with the quantity of LDL linoleic acid (r = 0.23, P = 0.04) and the 18:2-to-18:1 ratio (r = 0.52, P < 0.001). The oxidation rate was positively correlated with the 18:2-to-18:1 ratio (r = 0.24, P = 0.03)."
To lower n-6, cut SFA?

What?

So lowering SFA indeed made the LDL more resistant to oxidation. But it did so by lowering n-6 and raising MUFA in the LDL! SFA was basically unchanged.

A little Lipidology 101, MDA and HNE, mentioned above, aren't made from SFA, they're made from PUFA, and HNE is made exclusively from n-6. MDA and HNE pretty much are oxidized LDL. So you're not getting oxidized LDL from SFA in the body. It just won't happen.

Of course the authors don't mention that little fact. More below.

For some reason I am unable to explain, lowering SFA (16:0, palmitate in the chart) in the diet lowered n-6 (18:2, linoleate) in the LDL, and increased MUFA (18:2, oleate), protecting LDL from oxidation. SFA stayed  the same, basically.

My best guess is that it was the increased CHO in the diet (is this what's behind the Japanese diet, which is low in SFA and high in CHO?) but it is just a guess.
"In the present study, the ratios of 18:2 to 18:1 and PUFA to MUFA in the LDL from subjects when they consumed the Step-1 and Low-Sat diets were significantly lower than they were in the LDL from subjects when they consumed the AAD. Linoleic acid (n-6) in LDL from subjects when they consumed the Low-Sat diet also was significantly lower compared with those from subjects when they consumed the AAD. "
The first citation for this paper is:

"Oxidation of low-density lipoproteins: intraindividual variability and the effect of dietary linoleate supplementation"
"LDL oxidized faster after the linoleate diet than after the oleate diet... and produced more conjugated diene [that's bad] in proportion to the increase in LDL linoleate."
Here's where we get to the shaking my head part.

Why in blazes wouldn't you reduce the thing that is actually capable of causing the harm, as your first cite shows, and as your own study shows, is the source of the problem? Why keep n-6 flat and reduce something else, which through some round-about effect, lowers what you need to lower, the n-6?

Just lower the n-6 and you reduce the susceptibility for oxidation! They cite other papers that have done exactly that!

This study was done in 2000, did I mention that?

Think of the progress we would have made if they'd actually done what any engineer reading this paper would have told them to do. 
"N-6 converts to these toxins? You're proved that? Why not reduce the n-6?"
Let's not get too into conspiracies here, but on the face of it this study is clearly little more than a misleading advertisement for the sponsors listed above, who are forced to follow the United States Dietary Guidelines and replace saturated fats with the n-6 fat that their own research claims is harmful.




This post started with a twitter troll who cited the first-mentioned study:


Thursday, April 26, 2018

Breakfast with Low-Carb Dr. Tro Kalayjian

I'm the one with the bunny ears.

I had breakfast with Dr. Tro this morning in poverty-stricken Greenwich, Connecticut this morning, where I believe he treats gunshot wounds or stabbing victims, or something. Or maybe broken fingernails from Ferraris. Not too clear on that, actually...

He's a fascinating guy, he was morbidly obese (see pic below) until he decided to commit to a low-carb and then zero-carb (carnivore) diet. After initially thinking the whole notion of "fat adaption" was nonsense, he became a convert after discovering how it worked himself, with guidance from a bunch of folks, including (I hope) yours truly.

You'd never guess he was ever anything but lean and healthy. It's really quite remarkable.

He seems like he's got all the motivations to make an excellent, scientific doctor (which is not an easy thing!), and I hope he goes ahead and opens the practice we were discussing. He wants to help people with obesity, and show them how to "get off all their pills", so two thumbs up for that!

We also discussed training; if people can rebuild tendons and ligaments in the middle of life, which is a project we're both working on; and dreadful doctor-run blogs.

And a bunch of other stuff. See his post below and the replies, including my attempt to follow-up on some of our discussion points.


Wednesday, April 25, 2018

How Much Carbohydrates Should Humans Eat?

"Abstract: In the past, attempts have been made to estimate the carbohydrate contents of preagricultural human diets. Those estimations have primarily been based on interpretations of ethnographic data of modern hunter-gatherers. In this study, it was hypothesized that diets of modern hunter-gatherers vary in their carbohydrate content depending on ecoenvironments.

"Thus, using data of plant-to-animal subsistence ratios, we calculated the carbohydrate intake (percentage of the total energy) in 229 hunter-gatherer diets throughout the world and determined how differences in ecological environments altered carbohydrate intake. We found a wide range of carbohydrate intake (≈3%-50% of the total energy intake; median and mode, 16%-22% of the total energy). Hunter-gatherer diets were characterized by an identical carbohydrate intake (30%-35% of the total energy) over a wide range of latitude intervals (11°-40° north or south of the equator).

"However, with increasing latitude intervals from 41° to greater than 60°, carbohydrate intake decreased markedly from approximately equal to 20% to 9% or less of the total energy. Hunter-gatherers living in desert and tropical grasslands consumed the most carbohydrates (≈29%-34% of the total energy). Diets of hunter-gatherers living in northern areas (tundra and northern coniferous forest) contained a very low carbohydrate content (≤15% of the total energy).

"In conclusion, diets of hunter-gatherers showed substantial variation in their carbohydrate content. Independent of the local environment, however, the range of energy intake from carbohydrates in the diets of most hunter-gatherer societies was markedly different (lower) from the amounts currently recommended for healthy humans."
"Diets of modern hunter-gatherers vary substantially in their carbohydrate content depending on ecoenvironments: results from an ethnographic analysis"

Monday, April 16, 2018

"How fast can we run?"

"Marathon-ready Daniel Lieberman offers evolutionary perspective on Bannister 4-minute mile, human speed limits, and ‘Man Against Horse’".

"...He did talk about the kinds of shoes that he wore back in the day, and was fascinated by — and not particularly approving of — how running shoes had gotten so built up. He, like any fast miler, was a forefoot striker. We published a few years later the paper in which we made the argument that, essentially, prior to shoes pretty much everybody ran the way Bannister ran. He felt that was clearly the best way to run.

"I remember him describing how he had his shoes made by a cobbler in London. You couldn’t go to a shoe store back then and buy a pair of running shoes. He basically had to have his shoes custom made. I remember he discussed how hard it was to get the right kind of material — light but durable enough not to fall apart...."

Read the whole thing!

Saturday, March 31, 2018

"A Bunch of Running Nerds on Their Favorite Shoes"

Interesting list, with people like Magness, Dicharry, and Lieberman:

“I wear a variety of different shoes to mix it up, but all are zero drop, because I’m a forefoot striker and don’t need or want any cushioning on the heel, otherwise I end up running like a ballerina”...

Friday, March 30, 2018

"The Western Diet and Lifestyle and Diseases of Civilization"

Apparently a must-read paper, according to the interviewer of one of the authors:

"Do Traditional People Hold the Key to a Healthy Life? 15 Questions with Researcher Pedro Carrera Bastos"

Don't know how I missed this. The other authors: Maelan Fontes-Villalba, James H O’Keefe, Staffan Lindeberg, Loren Cordain.

"Regarding dietary changes, it should be mentioned
that, in the US, dairy products, cereal grains (especially the
refined form), refined sugars, refined vegetable oils, and
alcohol make up to 70% of the total daily energy consumed."

Tuesday, January 30, 2018

"My first podcast interview, over at Break Nutrition"

Great interview, of one of the smarter guys out there, with an amazing story.

Link via The High-fat Hep C Diet

Iron Overload: A Myth in Healthy People?

tl;dr: Oft-mentioned iron overload does not appear to be a problem in healthy humans, only in those with genetic defects. Iron is steadily lost through normal mechanisms and regained through dietary intake. Deficiency is the problem in healthy people.

So sometimes I get curious.


This post has moved to Substack.


Sunday, January 28, 2018

Meta-analysis of Oxidative Stress and Alzheimer's

No clear effect, little research. Did not look at focal analysis of specific regions or organelles.

"The field of oxidative stress as it relates to AD is large, with primary data coming from many different systems and supplemented by a large and rapidly growing narrative review literature. While this volume of data indicates intense interest in this topic, its utility is diminished by obfuscating or masking the complete picture of the oxidative changes in the AD brain. The purpose of this analysis was to quantitatively address this problem specifically for oxidative-stress related changes in the human AD brain. The pattern of oxidative changes identified in this analysis suggests that the antioxidant enzyme system in the brain is largely intact in AD and the global accumulation of oxidative damage is less substantial than has generally been reported."

And this:

"While this [brain malondialdehyde (MDA) level] is not the most specific or robust marker of lipid peroxidation, it is the most commonly studied marker of lipid peroxidation in AD brain..."

Sigh.

An excellent, comprehensive meta-analysis, well worth reading just to admire the work.

"Markers of oxidative damage to lipids, nucleic acids and proteins and antioxidant enzymes activities in Alzheimer's disease brain: A meta-analysis in human pathological specimens"

Tuesday, January 23, 2018

"Hello, Can We Have Your Liver?": Understanding a High-PUFA Diet.

tl;dr: A diet high in omega-6 and omega-3 polyunsaturated fatty acids has some positive effects on the body: lower weight gain, better preservation of lean mass, improved blood lipids, and increased brown adipose tissue; but also results in increased oxidative stress, mitochondrial dysfunction, and beginning of progressive liver failure.

This paper's a classic
"Fat Quality Influences the Obesogenic Effect of High Fat Diets [HFD]"
Sounds benign enough, right?  We all like quality fats...
"To investigate whether polyunsaturated fats could attenuate the above deleterious effects of high fat diets, energy balance and body composition were assessed after two weeks in rats fed isocaloric amounts of a high-fat diet (58.2% by energy) rich either in lard or safflower/linseed oil. Hepatic functionality, plasma parameters, and oxidative status were also measured. The results show that feeding on safflower/linseed oil diet attenuates the obesogenic effect of high fat diets and ameliorates the blood lipid profile...."
That's terrific!  So we just need to eat more omega-6 and omega-3 fats, and we'll be thinner with better blood cholesterol!

Post has been moved to Substack.

Tuesday, January 16, 2018

DNA Heritage Test Results Depend on The Company Used


"How DNA Testing Botched My Family's Heritage, and Probably Yours, Too"

Seems like it's more about entertainment that knowledge at this point...
"Four tests, four very different answers about where my DNA comes from—including some results that contradicted family history I felt confident was fact. What gives?

"There are a few different factors at play here.

"Genetics is inherently a comparative science: Data about your genes is determined by comparing them to the genes of other people..."

Sunday, January 7, 2018

"Penile Frostbite: an Unforeseen Hazard of Jogging"

I can't bring myself to quote the part of this that I want to, but this is just after...

"Spouse's observations of therapy produced rapid onset of numerous, varied and severe side effects (personal communication)."

Make sure you're not holding a beverage, but read the whole thing!

From Alex Hutchinson on Twitter.

You Can't Outrun a Bad Diet...

"Blood Glucose Levels of Subelite Athletes During 6 Days of Free Living"

"Ath03 consumed on average ~150 g of carbohydrate less than the lower recommended limit, 1770 kcal less than required (Table 2) and was the only participant to demonstrate a significant amount time below 4.0 mmol/L."

Duh. Even athletes can't cope with too much Modern American Diet .

Saturday, January 6, 2018

"How to Survive the Most Frigid Winter Runs"

Great article.

17 F, almost time for long pants.
Dressing to be comfortable when you've warmed up is the key. This is the art, and can be tricky at times!

I had a run recently where I managed to be cold for the first 30 minutes of a 2-hour run, but after that it was perfect. Literally felt like spring-time for the rest of the run, but was ~15F.

Adaptation is also key, it happens a lot more quickly to cold than to heat, in my experience, but can be a lot more unpleasant in the cold!