Mastering Nutrition

Hi, I'm Chris Masterjohn and I have a PhD in Nutritional Sciences. I am an entrepreneur in all things fitness, health, and nutrition. In this show I combine my scientific expertise with my out-of-the-box thinking to translate complex science into new, practical ideas that you can use to help yourself on your journey to vibrant health. This show will allow you to master the science of nutrition and apply it to your own life like a pro.
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Mastering Nutrition



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Now displaying: August, 2016
Aug 24, 2016

In episode 23, I explained why ketogenesis isn't all about carbs and insulin. Here in episode 25, I explained why insulin resistance isn't all about carbs and insulin. If that doesn't sound crazy, let me put it this way: forget carbs; I'll even say insulin resistance isn't all about insulin.

We start with a riddle: what do obesity, exercise, cigarette smoking, and diets rich in fruits and vegetables all share in common? Hint: it's a centrally important physiological response to each of them that mediates their health effects.

In the course of answering this riddle, I explain the underlying physiology that I consider most important to "insulin resistance" and why I believe insulin resistance is best viewed as subset of something far more important. I conclude by outlining practical strategies to prevent and reverse it.

In this episode, you will find all of the following and more:

Why would an individual cell "decide" to stop responding to insulin?; the limitations of using blood insulin and glucose concentrations as a primary metric of insulin resistance are similar to the limitations of assessing your level of "boss resistance" by the number of phone calls you decline from your boss when you skip work; why your pancreas is sort of like your boss; reactive oxygen species (ROS) are central to the physiology; ROS inhibit aconitase and shunt internal energy toward fat storage; ROS inhibit further intake of energy; ROS inhibit fatty acid uptake into mitochondria; ROS inhibit glucose uptake; ROS increase the expression of the entire antioxidant system and xenobiotic defense system; Subbing players on the field in team sports provides a useful analogy to understand why ROS-mediated inhibition of cellular energy uptake is health-promoting when other cells can fill in; insulin resistance isn't all about insulin; some responses to cellular energy overload antagonize insulin; others mimic insulin; obesity vs. exercise; AMPK activation makes the net effects of ROS in exercise very different from obesity; micronutrient intake determines whether net effects of ROS support antioxidant defense; glutathione synthesis depends on both nutrients and insulin sensitivity and stimulation; insulin resistance isn't all about ROS. It's about the context in which ROS operate; the net hormetic pro-oxidant effects of fruits and vegetable polyphenol; the net toxic pro-oxidant effects of cigarette smoking; again, net effects of ROS aren't about ROS; their about the context in which ROS operate; nutrient density as a practical strategy in insulin resistance; body composition as a practical strategy in insulin resistance; low-carbohydrate diets as a useful practical strategy for body composition, with potential limitations in the long-term because of the importance of carbohydrates for antioxidant defense.

Aug 20, 2016

Whites have higher 25(OH)D than every other racial group, and the conventional explanation is that light skin evolved to allow sufficient vitamin D synthesis far away from the equator. In episode 24, I explain why these differences may relate to genetics of vitamin D metabolism that have nothing to do with skin color and may reflect a lower average need for 25(OH)D rather than a lower average ability to get enough. But "average" is the key word and when it comes to using this information on a practical level we need to look beyond racial categories and treat each person as an individual.

In this episode, you'll find all of the following and more: should I offer online nutrition classes?; this will start of sounding like it's about racial groups, but it's really about individuals; blacks in America have lower 25 (OH)D than whites; the conventional hypothesis explains this as dark skin being poorly adapted to these latitudes; genetic evidence suggests light skin began evolving long after the migration from Africa; aggregate global 25(OH)D data do not support the conventional hypothesis; Caucasians have higher average 25 (OH)D than non-Caucasians at every latitude; Caucasians have higher average 25 (OH)D at temperate latitudes than non-Caucasians have at equatorial latitudes; blacks in America have higher bone mineral content than whites; calcitriol dominance favors getting calcium from our food, while PTH dominance favors getting calcium from our bones; genetic variation in the 1-hydoxylase can account for the difference in 25(OH)D between blacks and whites in America, but this has nothing to do with skin color or racial groups in the way we have socially defined them; calcium intake could influence how the genetic variation translates into 25(OH)D; this does not affect white 25 (OH)D, and it could be related to calcium intake; ancestral calcium intake could have mediated selective pressure on the relevant genes; blacks in the United States have higher average calcitriol and a higher average calcitriol-to-PTH ratio than whites; similar differences between Inuit and Danes: lower 25(OH)D, higher calcitriol, and lower PTH; a traditional diet raises 25(OH)D, raises calcitriol further, and suppresses PTH further; Asians have lower 25 (OH)D than whites in Hawaii; the references ranges may in effect be applying average white requirements to drive recommendations for everyone; the Maasai and Hadza have higher 25 (OH)D, but this may be due to  higher calcium intakes, and/or higher ancestral calcium intakes that influenced their genetics; non-whites are probably adapted to lower 25 (OH)D than whites on average, but it is individual genetics rather than racial groups that are relevant; 25 (OH)D + calcitriol can be summed for a biological activity index; PTH should be in the lower half of the reference range; magnesium deficiency could confound the PTH measurement, but it probably has to be extreme.


Aug 9, 2016

This episode is part personal story, part practical how-to guide, and part insight. The insight I want to emphasize here is one that I think is far too often overlooked: sometimes we shouldn't be trying to lose weight because the time isn't right.

But if the time is wrong, how can we know? And once we know, what can we do to prepare our bodies for weight loss and allow the time to become right? The short answer is that if weight gain is due to stress, I strongly believe we should always destress first. For the detailed answer, listen in.

In this episode, you will find the following and more: why there is a time to lose weight and a time not to; why calories-in calories-out (CICO) is like gravity; the right approach to weight loss is likely to be the one that incorporates 2-3 intuitive principles that allow you to sustain a caloric deficit while feeling satiated and energetic; there are a lot of those principles, so the 2-3 that work best for you probably has less to do with their general efficacy and more to do with your own personal psychological and behavioral traits; my skinny teens, my powerlifting/bodybuilding musclehead body, my grad school-induced dad bod, getting my postdoc fatso on, putting 6-7" on my waist in my first semester as a professor; it all turned around when I read Tim Ferris's 4-Hour Workweek; running on a treadmill while sleeping 10 hours a day, traveling to destress, gaining with CrossFit, leaning out with CrossFit; using the greyhound formula recommended by Alan Aragon and Brad Schoenfeld in The Lean Muscle Diet; using MyFitnessPal to track calories as recommended by CrossFit South Brooklyn; R-Lipoic acid, D-biotin, acetyl-L carnitine, coenzyme Q10 (CoQ10), coenzyme B vitamins to smooth out energy between meals; Headspace app or other mindfulness meditation, yoga, dance, martial arts, could help self-awareness, the key to knowing when the time is right; destressing is the key to make the time right when it's wrong; resisting social pressure and self pressure to lose weight is, ironically, the key to making the time right to lose weight.

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