The Digest - March 22

Quite a few interesting articles & studies this week:  

  • Low testosterone significantly increases risk of Type II Diabetes, Obesity, and Cardiovascular disease in men, as this article explains. I bring this up because data over the past few years has revealed an epidemic of low testosterone among men in the modern world, including among certain types of athletes (mainly endurance and ultra-endurance athletes)!! In the general population, low testosterone is primarily caused by lack of physical activity and exposure to environmental pollutants and hormone disruptors (plastics, smoking, air pollution, shampoos & hygiene products, etc). Testosterone production in men is linked to muscle growth in response to the types of stress induced by lifting heavy objects, another reason why I'm a fan of focusing on lifting heavy weights for short reps in the gym, especially for endurance athletes.^


  • Ok so this one is partly humorous but on a serious scientific note, the challenges that these surgeons overcame do reflect a major advancement in medicine and surgery: the world's first successful penis transplant has taken place in South Africa. If you want the details, read the article :-)^


  • Another potentially misleading article: the article reports that a new study links salt intake to damage to blood vessels, heart, kidneys, and brain (in addition to hypertension). But if you read the study, you will note that the scientists are linked "dietary sodium" to these effects, not salt. I bring this up because people need to distinguish between commercial processed / table salt, which is extremely high in sodium, and proper unprocessed sea salt, which has far less sodium and is balanced with a number of other minerals favorable to human health. I've talked about the difference between "commercial salt" and "proper sea salt" before, if you're interested.^



  • Earlier this week I sent a post dedicated to a new study which came out demonstrating how a simple treadmill test was shown to be a better predictor of mortality (including from cardiovascular disease) than "traditional" indicators (e.g. cholesterol, blood pressure, etc).^


  • Often times when I go to a commercial gym I see people doing one of 2 things: spending hours on the treadmill or doing hundreds of abdominal exercises, all in an attempt at shedding body fat. I commend them for their perseverance and drive, and I'm often tempted to go up to them and share the knowledge that neither chronic cardio nor abdominal exercises will help in losing weight… In fact, a recent study just published compared 2 groups of women over a 3-month period: diet only and diet+abdominal exercises. The results: no significant difference in weight loss, abdominal fat, body fat %, or skin fold.^


  • Many get into running (or other endurance sports) primarily to lose weight. However I often say that you cannot "out-train" a bad diet… This observational study from Aarhus University in Denmark followed over 500 novice runners over a 12-month period, comparing those who combined running with changed to their diet vs. those who didn't. The results were clear and significant: running+diet significantly more effective at fat loss compared with running alone.^


  • I'm a HUGE fan of raw nuts as part of a healthy diet. Most of them are packed with micronutrients and healthy fats. Are you wondering if some nuts are better than others? How to store raw nuts at home to avoid them becoming rancid? All this and more in the Definitive Guide to Nuts by the legendary Mark Sisson.^