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Showing posts from August, 2010

How to become diabetic in 6 hours!? Thanks Dr. Delgado for bringing science to the masses!

(Note: My apologies for the sarcastic tone of this post. I am not really congratulating anybody here!) Dr. Nick Delgado shows us in this YouTube video how to "become diabetic" in 6 hours! I must admit that I liked the real-time microscope imaging, and wish he had shown us more of that. But really! After consulting with my mentor, the MIMIW , I was reminded that there is at least one post on this blog that shows how one can "become diabetic" in just over 60 minutes – that is, about 6 times faster than using the technique described by Dr. Delgado. The technique used in the post mentioned above is called "intense exercise", which is even believed to be health-promoting! (Unlike drinking olive oil as if it was water, or eating white bread.) The advantage of this technique is that one can "become diabetic" by doing something healthy! Thanks Dr. Delgado, your video ranks high up there, together with this Ali G. video , as a fine example of how to bri

Heavy physical activity may significantly reduce heart disease deaths, especially after age 45

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The idea that heavy physical activity is a main trigger of heart attacks is widespread. Often endurance running and cardio-type activities are singled out. Some people refer to this as “death by running”. Others think that strength training has a higher lethal potential. We know based on the Oregon Sudden Unexpected Death Study that this is a myth . Here is some evidence that heavy physical activity in fact has a significant protective effect. The graph below, from Brooks et al. (2005) shows the number of deaths from coronary heart disease, organized by age group, in longshoremen (dock workers). The shaded bars represent those whose level of activity at work was considered heavy. The unshaded bars represent those whose level of activity at work was considered moderate or light (essentially below the “heavy” level). The data is based on an old and classic study of 6351 men, aged 35 to 74 years, who were followed either for 22 years, or to death, or to the age of 75. It shows a signific

Lipotoxicity or tired pancreas? Abnormal fat metabolism as a possible precondition for type 2 diabetes

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The term “diabetes” is used to describe a wide range of diseases of glucose metabolism; diseases with a wide range of causes. The diseases include type 1 and type 2 diabetes, type 2 ketosis-prone diabetes (which I know exists thanks to Michael Barker’s blog ), gestational diabetes, various MODY types, and various pancreatic disorders. The possible causes include genetic defects (or adaptations to very different past environments), autoimmune responses, exposure to environmental toxins, as well as viral and bacterial infections; in addition to obesity, and various other apparently unrelated factors, such as excessive growth hormone production. Type 2 diabetes and the “tired pancreas” theory Type 2 diabetes is the one most commonly associated with the metabolic syndrome, which is characterized by middle-age central obesity, and the “diseases of civilization” brought up by Neolithic inventions. Evidence is mounting that a Neolithic diet and lifestyle play a key role in the development of

The theory of supercompensation: Strength training frequency and muscle gain

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Moderate strength training has a number of health benefits, and is viewed by many as an important component of a natural lifestyle that approximates that of our Stone Age ancestors. It increases bone density, muscle mass, and improves a number of health markers. Done properly, it may decrease body fat percentage. Generally one would expect some muscle gain as a result of strength training. Men seem to be keen on upper-body gains, while women appear to prefer lower-body gains. Yet, many people do strength training for years, and experience little or no muscle gain . Paradoxically, those people experience major strength gains, both men and women, especially in the first few months after they start a strength training program . However, those gains are due primarily to neural adaptations, and come without any significant gain in muscle mass . This can be frustrating, especially for men. Most men are after some noticeable muscle gain as a result of strength training. (Whether that is healt

What can beetles tell us about slowing aging? Answers are in the mitochondria

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Mitochondrial genes influence life expectancy in beetles, a new study reports. Genetic research into aging and longevity revolves mainly around the nuclear genome, which encodes most of our multicellular bodies, but a new Monash University study performed on beetles suggests shifting focus to the mitochondrial genome.   The mitochondria—kidney-shaped organelles often referred to as the cell's powerhouses—each contain their own set of DNA, passed on from mother to offspring, and according to the study, it's these strands that may hold key genes that determine one's life expectancy, at least in bugs.   The study, published in the August issue of The American Naturalist , found evidence that particular combinations of genes (haplotypes) in the mitochondrial genome influenced lifespan in a species of seed beetles ( Callosobruchus maculates ).   As a result, the research supports growing evidence that particular mitochondrial gene combinations could also play a major role in

How to win her heart? Moderate amounts of dark chocolate

They say chocolate is the way to a woman's heart, and they could be right – eating one or two servings of dark chocolate weekly is good for the hearts of middle-aged or elderly women. A nine-year observational study followed 31,823 healthy Swedish women ages 48 to 82 and found that those who ate moderate amounts of high-quality chocolate had healthier hearts. The women who gained the most heart-health benefits had eaten one or two servings of the dark chocolate weekly, followed by those who ate one to three servings monthly. Each serving of chocolate was typically between 19 and 30 grams. On the other hand, the women who ate one or more servings per day received no benefit, which the researchers suggest was result of replacing other nutritious foods with the chocolate. So, enjoy dark chocolate, but in moderation and as part of a nutritious diet. Men, take note – the quality of the chocolate matters. Finding the right chocolate for a woman’s heart health, while avoiding the pitfalls

The evolution of costly traits: Competing for women can be unhealthy for men

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There are human traits that evolved in spite of being survival handicaps. These counterintuitive traits are often called costly traits, or Zahavian traits (in animal signaling contexts), in honor of the evolutionary biologist Amotz Zahavi (Zahavi & Zahavi, 1997). I have written a post about this type of traits, and also an academic article (Kock, 2009). The full references and links to these publications are at the end of this post. The classic example of costly trait is the peacock’s train, which is used by males to signal health to females. (Figure below from: animals.howstuffworks.com.) The male peacock’s train (often incorrectly called “tail”) is a costly trait because it impairs the ability of a male to flee predators. It decreases a male’s survival success, even though it has a positive net effect on the male’s reproductive success (i.e., the number of offspring it generates). It is used in sexual selection; the females find big and brightly colored trains with many eye spot

Resveratrol-Rich Plant Extract Stifles Inflammation in Humans

Resveratrol’s antioxidant and anti-inflammation actions shown previously only in vitro and in laboratory animals have now been observed in a small human study. State University of Buffalo New York and Kaleida Health researchers found that supplementation with a plant extract containing resveratrol suppressed generation of free radicals called reactive oxygen species (ROS) and reduced expression of two major proinflammatory pathways. Writing in their study, published in Journal of Clinical Endocrinology and Metabolism, the researchers state that they have demonstrated for the first time in humans “comprehensive effects on ROS generation and inflammation” and the “antiaging action of resveratrol.” In the trial, two groups of 10 healthy adults were randomized to receive placebo or 200 milligrams of Japanese knotweed extract (Polygonum cuspidatum) supplying 40 milligrams of resveratrol daily. Fasting blood samples were collected before, during and after six weeks of supplementation. Subjec

Nonexercise activities like fidgeting may account for a 1,000 percent difference in body fat gain! NEAT eh?

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Some studies become classics in their fields and yet are largely missed by the popular media. This seems to be what happened with a study by Levine and colleagues (1999; full reference and link at the end of this post), which looked at the role that nonexercise activity thermogenesis (NEAT) plays in fat gain suppression. Many thanks go to Lyle McDonald for posting on this. You have probably seen on the web claims that overeating leads to fat loss, because overeating increases one’s basal metabolic rate. There are also claims that food has a powerful thermic effect, due to the energy needed for digestion, absorption and storage of nutrients; this is also claimed to lead to fat loss. There is some truth to these claims, but the related effects are very small compared with the effects of NEAT. Ever wonder why there are some folks who seem to eat whatever they want, and never get fat? As it turns out, it may be primarily due to NEAT! NEAT is associated with fidgeting, maintenance of postu

Cortisol, surprise-enhanced cognition, and flashbulb memories: Scaring people with a snake screen and getting a PhD for it!

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Cortisol is a hormone that has a number of important functions. It gets us out of bed in the morning, it cranks up our metabolism in preparation for intense exercise, and it also helps us memorize things and even learn. Yes, it helps us learn . Memorization in particular, and cognition in general, would be significantly impaired without cortisol. When you are surprised, particularly with something unpleasant, cortisol levels increase and enhance cognition. This is in part what an interesting study suggests; a study in which I was involved. The study was properly “sanctified” by the academic peer-review process (Kock et al., 2009; full reference and link at the end of this post). The main hypothesis tested through this study is also known as the “ flashbulb memorization ” hypothesis. Interestingly, up until this study was conducted no one seemed to have used evolution to provide a basis on which flashbulb memorization can be explained. The basic idea here is that enhanced cognition with

The baffling rise in seasonal allergies: Global warming or obesity?

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The July 26, 2010 issue of Fortune has an interesting set of graphs on page 14. It shows the rise of allergies in the USA, together with figures on lost productivity, doctor visits, and medical expenditures. (What would you expect? This is Fortune, and money matters.) It also shows some cool maps with allergen concentrations, and how they are likely to increase with global warming. (See below; click on it to enlarge; use the "CRTL" and "+" keys to zoom in, and CRTL" and "-" to zoom out.) The implication: A rise in global temperatures is causing an increase in allergy cases. Supposedly the spring season starts earlier, with more pollen being produced overall, and thus more allergy cases. Really!? I checked their numbers against population growth, because as the population of a country increases, so will the absolute number of allergy cases (as well as cancer cases, and cases of almost any disease). What is important is whether there has been an increa

Growth hormone, insulin resistance, body fat accumulation, and glycogen depletion: Making sense of a mysterious hormone replacement therapy outcome

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Hormone replacement therapies are prescribed in some cases, for medical reasons. They usually carry some risks. The risks come in part from the body down-regulating its own production of hormones when hormones are taken orally or injected. This could be seen as a form of compensatory adaptation , as the body tries to protect itself from abnormally high hormone levels. More often than not the down-regulation can be reversed by interrupting the therapy. In some cases, the down-regulation becomes permanent, leading to significant health deterioration over the long run. One can seriously regret having started the hormone replacement therapy in the first place. The same is true (if not more) for hormone supplementation for performance enhancement, where normal hormone secretion levels are increased to enhance (mostly) athletic performance. Rosenfalck and colleagues (1999) conducted an interesting study linking growth hormone (GH) replacement therapy with insulin resistance. Their conclusion