Articles About Health And Fitness

Yesterday, the Dan's Plan blog Eat Move Sleep published a blog post I wrote about sleep, artificial light, your brain, and a free computer program called f.lux that can help us live healthier lives.  Head over to Eat Move Sleep to read it.

Evidence is steadily accumulating that insufficient sleep increases the risk of obesity and undermines fat loss efforts.  Short sleep duration is one of the most significant risk factors for obesity ( 1 ), and several potential mechanisms have been identified, including increased hunger, increased interest in calorie-dense highly palatable food, reduced drive to exercise, and alterations in hormones that influence appetite and body fatness.  Dan Pardi presented his research at AHS13 showing that sleep restriction reduces willpower to make healthy choices about food. We also know that genetics has an outsized influence on obesity risk, accounting for about 70 percent of the variability in body fatness between people in affluent nations ( 2 ).  I have argued that "fat genes" don't directly lead to obesity, but they do determine who is susceptible to a fattening environment and who isn't ( 3 ).  I recently revisited a 2010 paper published in the journal Sleep by Universi...

My friend Pedro Bastos graciously invited me to speak at a conference he organized in Lisbon on October 5 titled "Food, Nutrition and the Prevention of Chronic Diseases".  I will give two talks: "Ancestral Health: What is Our Human Potential?"  This talk will explore the health of non-industrial cultures in an effort to understand how much of our modern chronic disease burden is preventable, and it will briefly touch on one major aspect of non-industrial life that may protect against the "diseases of civilization".  This presentation will focus on age-adjusted data from high quality studies.   "Why Do We Overeat: a Neurobiological Perspective."  This talk will attempt to explain why most of us consume more calories than we need to maintain weight-- a phenomenon that is a central cause of morbidity and mortality in the modern world.  It will touch on some of the brain mechanisms involved in ingestive behavior, and outline a framework to explain wh...

[Note: in previous versions, I mixed up "LGI" and "HGI" terms in a couple of spots.  These are now corrected.  Thanks to readers for pointing them out.] Recently, a new study was published that triggered an avalanche of media reports suggesting that refined carbohydrate may be addictive: Refined Carbs May Trigger Food Addiction Refined Carbs May Trigger Food Addictions Can You be Addicted to Carbs? etc. This makes for attention-grabbing headlines, but in fact the study had virtually nothing to do with food addiction.  The study made no attempt to measure addictive behavior related to refined carbohydrate or any other food, nor did it aim to do so. So what did the study actually find, why is it being extrapolated to food addiction, and is this a reasonable extrapolation?  Answering these questions dredges up a number of interesting scientific points, some of which undermine popular notions of what determines eating behavior. Read more »

Now that the concept of cold training for cold adaptation and fat loss has received scientific support, I've been thinking more about how to apply it.  A number of people have been practicing cold training for a long time, using various methods, most of which haven't been scientifically validated.  That doesn't mean the methods don't work (some of them probably do), but I don't know how far we can generalize individual results prior to seeing controlled studies. The studies that were published two weeks ago used prolonged, mild cold exposure (60-63 F air) to achieve cold adaptation and fat loss ( 1 ,  2 ).  We still don't know whether or not we would see the same outcome from short, intense cold exposure such as a cold shower or brief cold water plunge.  Also, the fat loss that occurred was modest (5%), and the subjects started off lean rather than overweight.  Normally, overweight people lose more fat than lean people given the same fat loss intervention, but t...

I just returned from the 2013 Ancestral Health Symposium in Atlanta.  Despite a few challenges with the audio/visual setup, I think it went well. I arrived on Thursday evening, and so I missed a few talks that would have been interesting to attend, by Mel Konner, Nassim Taleb, Gad Saad, and Hamilton Stapell.  Dr. Konner is one of the progenitors of the modern Paleo movement.  Dr. Saad does interesting work on consummatory behavior, reward, and its possible evolutionary basis.  Dr. Stapell is a historian with an interest in the modern Paleo movement.  He got some heat for suggesting that the movement is unlikely to go truly mainstream, which I agree with.  I had the opportunity to spend quite a bit of time with him and found him to be an interesting person. On Friday, Chris Kresser gave a nice talk about the potential hidden costs of eradicating our intestinal parasites and inadvertently altering our gut flora.  Unfortunately it was concurrent with Chri...

For those who are attending the Ancestral Health Symposium this year, my talk will be at 9:00 AM on Saturday.  The title is "Insulin and Obesity: Reconciling Conflicting Evidence", and it will focus on the following two questions: Does elevated insulin cause obesity; does obesity cause elevated insulin; or both? Is there a unifying hypothesis that's able to explain all of the seemingly conflicting evidence cited by each side of the debate? I'll approach the matter in true scientific fashion: stating hypotheses, making rational predictions based on those hypotheses, and seeing how well the evidence matches the predictions.  I'll explore the evidence in a way that has never been done before (to my knowledge), even on this blog. Why am I giving this talk?  Two reasons.  First, it's an important question that has implications for the prevention and treatment of obesity, and it has received a lot of interest in the ancestral health community and to some extent amon...