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Showing posts from May, 2011

Interview with Jimmy Moore, and basics of intima-media thickness and plaque tests

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Let me start this post by telling you that my interview with Jimmy Moore is coming up in about a week . Jimmy and I talk about evolution, statistics, and health – the main themes of this blog. We talk also about other things, and probably do not agree on everything. The interview was actually done a while ago, so I don’t remember exactly what we discussed. From what I remember from mine and other interviews (I listen to Jimmy's podcasts regularly), I think I am the guest who has mentioned the most people during an interview – Gary Taubes, Chris Masterjohn, Carbsane, Petro (a.k.a., Peter “the Hyperlipid”), T. Colin Campbell, Denise Minger, Kurt Harris, Stephan Guyenet, Art De Vany, and a few others. What was I thinking? In case you listen and wonder, my accent is a mix of Brazilian Portuguese, New Zealand English (where I am called “Need”), American English, and the dialect spoken in the “country” of Texas. The strongest influences are probably American English and Brazilian Portugu

Fitness, hunter-gatherer style

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Aché man hunting. Credit: Wiki “So the bottom line is that foragers are often in good shape and they look it. They sprint, jog, climb, carry, jump, etc all day long but are not specialists.” The quote above is excerpted from a description given by anthropologist Kim Hill (whose work I've previously written about here ) of his experience observing the behaviors of the Aché of Paraguay and the Hiwi of Venezuela. The ASU professor, who has been living and studying the tribes for more than 30 years, recently had his work highlighted in a commentary published in Progress in Cardiovascular Diseases . The article, whose lead author was James O'Keefe, MD, examines the daily physical activity patterns among hunter gatherers and fossil hominins. According to the authors, ancestral hunter-gatherers expended as much as five times more amounts of energy on physical activity than the average modern sedentary adult. Based on data from Cordain's earlier work and that of colleagues, the ar

The China Study II: Wheat may not be so bad if you eat 221 g or more of animal food daily

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In previous posts on this blog covering the China Study II data we’ve looked at the competing effects of various foods, including wheat and animal foods. Unfortunately we have had to stick to the broad group categories available from the specific data subset used; e.g., animal foods, instead of categories of animal foods such as dairy, seafood, and beef. This is still a problem, until I can find the time to get more of the China Study II data in a format that can be reliably used for multivariate analyses. What we haven’t done yet, however, is to look at moderating effects. And that is something we can do now.  A moderating effect is the effect of a variable on the effect of another variable on a third. Sounds complicated, but WarpPLS  makes it very easy to test moderating effects. All you have to do is to make a variable (e.g., animal food intake) point at a direct link (e.g., between wheat flour intake and mortality). The moderating effect is shown on the graph as a dashed arrow goin

How Neandertals Lived, Hunted, and Ate

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This Discovery Channel series "Neanderthal" presents a wonderful re-enactment of how Neandertals lived in small groups, how they hunted together, and how they ate. I was especially taken by how much we know about the way they used tools to butcher meat, scraped animal hides (by holding the hides in their teeth and face as a tool to spread the stress around the skull) for use in making clothing (shown in Part 1). It's amazing that we know so much about these ancient peoples -- how strong they were, how intelligent, how adaptive, as said in the documentary. The scientific techniques mentioned that lend to our understanding of Neandertals are studies on fossilized feces, worn-out teeth from scraping animal hides, and bone fractures that reveal injuries that led to illness or death. New Neandertal Study I wonder what changes will have to be realized to this documentary in light of new research  from the Journal of Human Evolution . The linked article reports that new findings

Book review: Biology for Bodybuilders

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The photos below show Doug Miller and his wife, Stephanie Miller. Doug is one of the most successful natural bodybuilders in the U.S.A. today. He is also a manager at an economics consulting firm and an entrepreneur. As if these were not enough, now he can add book author to his list of accomplishments. His book, Biology for Bodybuilders , has just been published. (Source: www.dougmillerpro.com) Doug studied biochemistry, molecular biology, and economics at the undergraduate level. His co-authors are Glenn Ellmers and Kevin Fontaine. Glenn is a regular commenter on this blog, a professional writer, and a certified Strength and Conditioning Specialist. Dr. Fontaine is an Associate Professor at the Johns Hopkins University’s School of Medicine and Bloomberg School of Public Health. Biology for Bodybuilders is written in the first person by Doug, which is one of the appealing aspects of the book. This also allows Doug to say that his co-authors disagree with him sometimes, even as he out

Looking for a good orthodontist? My recommendation is Dr. Meat

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The figure below is one of many in Weston Price’s outstanding book Nutrition and Physical Degeneration  showing evidence of teeth crowding among children whose parents moved from a traditional diet of minimally processed foods to a Westernized diet. Tooth crowding and other forms of malocclusion are widespread and on the rise in populations that have adopted Westernized diets (most of us). Some blame it on dental caries, particularly in early childhood; dental caries are also a hallmark of Westernized diets. Varrela (2007) , however, in a study of Finnish skulls from the 15th and 16th centuries found evidence of dental caries, but not of malocclusion, which Varrela reported as fairly high in modern Finns. Why does malocclusion occur at all in the context of Westernized diets?  Lombardi (1982) put forth an evolutionary hypothesis: “In modern man there is little attrition of the teeth because of a soft, processed diet; this can result in dental crowding and impaction of the third molars

Those daily extra cups of joe not linked to hypertension

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An extra shot of espresso can surely help wake you up in the morning, but what does it mean for your blood pressure? It is well known that coffee's caffeine content can raise blood pressure temporarily, especially in people who have hypertension. Could habitually drinking high amounts have long-term effects on blood pressure too? Java lovers will rejoice in a large study's findings that more cups daily isn't associated with increased risk of hypertension. The study , published in American Journal of Clinical Nutrition on March 30, was a systematic review and meta-analysis that examined six prospective cohort studies. Two previous meta-analyses of randomized controlled trials found an association with slightly raised risk of hypertension. But these trials all lasted only 85 days or fewer days. In the new study, a total 172,567 participants and 37,135 incident cases of hypertension were followed over the course of six years. Four of the six studies evaluated reported a nonli

Diagnosing Darwin's multiple gastrointestinal diseases

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Charles Darwin (Credit: Wikimedia) Throughout most of Charles Darwin's adult life, the famed author of On the   Origin of Species struggled with repeated episodes of severe abdominal pain, nausea and vomiting that could last for hours at a time, often occurring about three hours after breakfast, and thought to have been brought on by times of emotional stress. England's physicians of the time could not properly diagnose the syndrome of cyclic vomiting, although they tried by suggesting its etiology was anything to do with allergies, gout, and mental overwork. But what of an assessment of Darwin's symptoms by modern physicians of today? On Friday, May 6, modern physicians gathered to discuss Darwin's lifelong illness at the 18th Historical Clinicopathological Conference sponsored by University of Maryland Health Care System. The conference previously has examined and provided modern medical diagnoses of other prominent historical figures such as Abraham Lincoln and Edga

Getting off the death chair

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My stand-up desk As bipedal apes, our bodies are meant for walking and running, which may have even been a catalyst for eventually bringing about the means of evolving larger brains. Physical activity is strongly linked to brain performance. The exercise boosts blood flow in the brain and improves our memory and cognitive function. Exercise acts like a trigger for the brain saying, "It's time to be alert, find food, survive." Exercise may even fuel brain power by increasing neurogenesis and also guard against the harmful effects of stress. Yet now we sit, and sit, and sit. Until the sitting kills us. This article in the New York Times magazine gives a pretty good description of just what really happens when you sit in that death chair with quotes from Marc Hamilton, an inactivity researcher at the Pennington Biomedical Research Center: This is your body on chairs: Electrical activity in the muscles drops — “the muscles go as silent as those of a dead horse,” Hamilton

Safe weight loss for seniors through diet and exercise

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In the United States, the number of obese older adults has reached disturbing heights—now affecting approximately 20 percent of those ages 65 and older—and is only expected to rise as more Baby Boomers become senior citizens. Weight loss through calories reduction or exercise are generally good for most people as an intervention in obesity, although the appropriateness of these methods has historically been a matter of controversy in older, obese adults. A major concern with weight loss is the accompanying loss of lean tissue, which can accelerate existing sarcopenia (age-related loss of muscle and strength), and result in reduction of bone mineral density that could worsen frailty. This could lead to greater risk of bone fractures and broken hips. Studies have yet to provide sufficient evidence, one way or another, as to whether or not weight loss provides a true enhancement to quality of life. In a one-year, randomized, controlled trial, researchers from Washington University School

Printing organs for transplants

Advances in medicine are allowing us to live longer than ever, but with our older age comes a greater risk that our organs will fail us. In fact, the shortage of organs available for transplant increases by the day, according to Anthony Atala who spoke at TEDMED. In his talk, posted in March, Atala presents developments in regenerative medicine including new devices that use the same technology of scanners, fax, copy machines and printers. Instead of using ink in their cartridges, they simply use cells. On stage, Atala shows us how one of these devices works, actually printing a kidney in as little as seven hours. It's mind bending. I feel as though I'd like to show this video to every person I know. This is our future medicine. This technology will no doubt keep us living longer than ever. One day, like salamanders, we will be growing our own organs whenever needed -- kidneys, livers, lungs, etc. Can you even imagine? Eat and drink whatever you like, ruin your liver and kidney

News that "Nutcracker Man didn't eat nuts" isn't exactly news

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Photosimulation montages of "Nutcracker Man's" dental microwear. Reference: Ungar et al. PLoS One  2008.  Because of a huge jaw and large, flat molars,  Paranthrapus boisei  was nicknamed Nutcracker Man and thought to have eaten a diet comprised largely of hard nuts and seeds. But , it turns out, the hominin species who in evolutionary terms has been likened to our great uncle was more likely to have eaten soft fruits, leaves and grass, according to carbon stable isotope data just published in PNAS  by Thure Cerling and his team from University of Utah. See more about Cerling's paper on John Hawks's  blog . A big deal  has been made of this new paper and rightly so, but reporters should also note that the findings are a confirmation of what was already supposed based on dental microwear (shown above) almost exactly three years ago. On 30 April 2008, Peter Ungar and colleagues at University of Arkansas also told us Nutcracker Man didn't eat nuts in a study in

Michael Ruse on "Origins of Human Evolution"

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Michael Ruse Why were the great Greek philosophers (including Plato and Aristotle) firmly set against the idea of natural origins? Why were they so adamant that natural origins were impossible? According to Michael Ruse , a philosopher of biology at Florida State University, the reason is the problem of "final causes." Aristotle, for example, "could not see how something like this could come about through blind law," said Ruse in a lecture given at Arizona State University’s Origins Project Science and Culture Festival on April 7, 2011. This is why, for good scientific reason, said Ruse, they turned their back and rejected the idea of natural origins. What was the big move? Robert Boyle particularly put his finger on it, said Ruse, we’ve changed the thinking of the world as an organism, to the world as a clock. This was a new metaphor for the world—the world is at some level a machine. Going into the 18 th century, the ideology of progress began to emerge—people b

Resveratrol Improves Insulin Sensitivity in Humans

Low-dose supplementation of resveratrol daily may reduce oxidative stress and improve the body's sensitivity to insulin, a study from University of Pecs in Hungary suggests. In a double-blind, placebo-controlled study published in the British Journal of Nutrition , Hungarian researchers report observations that people with type 2 diabetes who take 5 milligrams of resveratrol twice daily improved their sensitivity to insulin after only our weeks. "The present study shows for the first time that resveratrol improves insulin sensitivity, which might be due to a resveratrol-induced decrease in oxidative stress that leads to more efficient insulin signaling via the Akt pathway," the authors concluded. The Akt pathway is a pathway involved in cellular uptake of glucose in response to insulin—it induces glucose transport, particularly into muscle cells. When working properly, insulin stimulates cells to take in glucose from the blood stream, thereby lowering circulating glucose

Strength training plus fasting regularly, and becoming diabetic!? No, it is just compensatory adaptation at work

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One common outcome of doing glycogen-depleting exercise (e.g., strength training, sprinting) in combination with intermittent fasting is an increase in growth hormone (GH) levels. See this post for a graph showing the acute effect on GH levels of glycogen-depleting exercise. This effect applies to both men and women, and is generally healthy, leading to improvements in mood and many health markers. It is a bit like GH therapy, with GH being “administered” to you by your own body. Both glycogen-depleting exercise and intermittent fasting increase GH levels; apparently they have an additive effect when done together. Still, a complaint that one sees a lot from people who have been doing glycogen-depleting exercise and intermittent fasting for a while is that their fasting blood glucose levels go up. This is particularly true for obese folks (after they lose body fat), as obesity tends to be associated with low GH levels, although it is not restricted to the obese. In fact, many people d