Tuesday 31 May 2016

Why you should avoid (vitamin D) supplements



Here's why:-
  • Under-appreciation of the fact that vitamin D is a hormone with diverse and dose-dependent systemic effects, still not fully understood
  • Misleading  claims that vitamin D supplementation is “equivalent”  to vitamin D from sun exposure. While the two forms are chemically identical, levels of vitamin D3 synthesized from sun exposure are self-limiting due to feedback regulation.  What happens when we chronically exceed natural limits?
  • Inadequate attention to the possible effects of chronic vitamin D supplementation on homeostatic down-regulation of the VDR receptor. See this discussion bv Dr. David Agus of USC medical school.
  • Inadequate study of the possible long term adverse effects of chronic vitamin D supplementation. Few studies look beyond 4 years. Hormone replacement therapy was in favor for 50 years before the risks came to light . Things don’t necessarily look any more promising when synthetic hormones are replaced bioidentical hormones.

Todd states there are several ways you can naturally activate autophagy in your body.  It turns out that all of them involve one form of hormesis or another:-
  • Calorie restriction and intermittent fasting.  In my post on Calorie restriction and hormesis,  I summarized some of the research on calorie restriction in humans, primates and other animals. including the role played by autophagy and other mechanisms.  This is also described in my talk onIntermittent Fasting for Health and Longevity.
  • Brief, strenuous exercise.  A 2012 paper in Nature by Levine et al. in mice found that “Exercise is even faster than starvation” at inducing autophagy… “If you just exercise the mice for 30 minutes on a treadmill, autophagosomes start to form. Thirty minutes of running induces autophagy 40 to 50 percent.”
  • Hormetic stress in general.   A wide range of short term, intense but sublethal stressors have been shown to activate autophagy via a common pathway.  Criollo et al.  showed that multiple stressors, including nutrient starvation and numerous chemicals, trigger the activation of the IKK (IκB kinase) complex, inducing the classical autophagy pathway involving p53 depletion, mTOR inhibition, AMPK and JNK1 activation, and release of the pro-autophagic protein Beclin-1.  How many of the other hormetic stressors we’ve discussed in this blog– such as cold showers–might effectively activate autophagy?