Posts Tagged ‘hormones’

What cold showers and exercise have in common

Posted 17 Feb 2014 — by Todd
Category Diet, Fitness, Hormesis, Uncategorized

lewisgordonpugh2PA1307_468xCan cold showers, winter plunges, and brisk walks in the chilly outdoors provide some of the same benefits as intense exercise—including weight loss and increased energy levels?  Such a link has been suspected, because cold exposure is known to convert metabolically docile white adipose tissue (WAT) into metabolically active brown adipose tissue (BAT). This “brown fat” helps you stay warmer and burn more energy.  But now there is some evidence that cold exposure doesn’t merely help you turn up your inner furnace, and burn off a little fat in the short term.  It may actually lower your body’s weight set point by activating a hormone that is also released during intense exercise.

That hormone is irisin (pronounced “EYE-rissin”), a cytokine produced in skeletal muscle.  From the initial evidence, irisin and its partner hormone FGF21 may provide lasting benefits by boosting your metabolism and inducing you to shed excess pounds. Read More

An alternative to vitamin D supplements?

Posted 11 Feb 2013 — by Todd
Category Diet, Fitness, Health, Hormesis

Screen Shot 2013-02-10 at 11.51.13 PMMy recent post on Why I don’t take vitamin D supplements generated a lot of interest and a few misconceptions.  In that article, I did not suggest any practical alternatives to taking high dose vitamin D supplements.  Here I will suggest a way that may provide the benefits of vitamin D without popping any pills, spending all day in the sun, or ingesting copious amounts of fish.

Some readers got the idea that I believe vitamin D is not beneficial, and that I discount the evidence from studies that show the benefits.  I want to dispel that notion.  I do acknowledge the key role that vitamin D and the vitamin D receptor (VDR) play in bone mineralization and regulation of  innate and adaptive immunity, and among other things.  I further acknowledge that many (but certainly not all) studies support an association between higher vitamin D3 levels and reduced incidence of diseases such as cancer.

As I wrote:

Nobody doubts the important role of vitamin D in the body. But are higher levels of a hormone like vitamin D–whether or not provided as a supplement– always a good thing?

My doubts are focused on several points:

  • 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.

My article created a dilemma for several commenters. These people acknowledged the risks, but nevertheless cited  benefits they personally experienced  from supplementing with vitamin D–ranging from fewer colds and flu, to relief of autoimmune symptoms, and even lessening of depression.

For these people, a key question remains:

Is there a way to get the benefits of vitamin D supplementation, while avoiding the dependency and risks of taking vitamin D capsules daily for the rest of your life?  While I don’t have a definitive proven answer to that question, recent research leads me to speculate here that there is a promising approach that is within everyone’s reach.

It lies within a powerful natural biological process called autophagy.

Read More

Why I don’t take vitamin D supplements

Posted 11 Nov 2012 — by Todd
Category Uncategorized

Vitamin D has been associated with numerous health benefits, including cardiovascular and immune health, bone strength, and prevention of cancer. However, studies claim that most of us are deficient in vitamin D, and thereby unnecessarily vulnerable to increased heart disease, stroke, cancer, diabetes, osteoporosis, infection and autoimmune disorders. According to a review of recent studies in Natural News, there is a woldwide epidemic of vitamin D deficiency:  59% of the population is “vitamin D deficient”.  The article goes onto to speculate that “What’s becoming increasingly clear from all the new research is that vitamin D deficiency may be the common denominator behind our most devastating modern degenerative diseases.”

Supplementation with vitamin D capsules is advocated even by “primal” advocate  Mark Sisson, normally one to take inspiration from our paleolithic ancestors, shunning medication and embracing a lifestyle of eating whole foods and engaging in moderately stressful, playful exercise:

We can’t all bask in the midday sun.. For those of us unable to run shirtless and shoeless through a sun kissed meadow…our option is oral intake… food will help, but it won’t suffice. You need something stronger. ..take a good D3 supplement if you can’t get real sunlight. As long as you don’t go overboard on the dosage, you’re good to go. If it’s not in an oil-based capsule, just take it with a bit of fatty food (not a stretch for an Primal eater). It travels the same pathway and results in the same benefits. It’s always easier to just let nature take its course, but it’s not always realistic. A good general rule is 4000 IU per day.

Therefore, we should supplement with vitamin D.  Right?

Not so fast.  A closer examination shows that low vitamin D levels may be a consequence, not a cause, of poor health.  And that supplementation with Vitamin D may actually be counterproductive.  Let me explain.

Read More