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