This paper is a classic example of single-variable-fallacy. The Vitamin D gurus (e.g. masterjohn. hollick) are consistent in saying that if one is supplementing with oral vitamin D then it is essential to supplement with vitamin K2 as well since K2 is involved in the regulation of calcium storage. I think magnesium and Vitamin A are also important for proper use of Vitamin D. There is now a good body of evidence that Vitamin D blood levels of 50 are a good level to shoot for and that is not achievable for most people (except with good sun exposure) without supplementation.There is no drug or supplement that has only positive effects. One should supplement vit D only when their levels are low.
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Role of vitamin D in vascular calcification: bad guy or good guy?
The role of vitamin D and its derivatives in vascular calcification is complex. It has long been known that in humans, hypervitaminosis D may be associatedacademic.oup.com
Predict estradiol, DHT, and free testosterone levels based on total testosterone
This tool provides predictions based on statistical models and should NOT replace professional medical advice. Always consult with your healthcare provider before making any changes to your TRT protocol.
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A form of estrogen produced from testosterone. Important for bone health, mood, and libido. Too high can cause side effects; too low can affect well-being.
Dihydrotestosterone is a potent androgen derived from testosterone. Affects hair growth, prostate health, and masculinization effects.
The biologically active form of testosterone not bound to proteins. Directly available for cellular uptake and biological effects.
Lakshman KM, Kaplan B, Travison TG, Basaria S, Knapp PE, Singh AB, LaValley MP, Mazer NA, Bhasin S. The effects of injected testosterone dose and age on the conversion of testosterone to estradiol and dihydrotestosterone in young and older men. J Clin Endocrinol Metab. 2010 Aug;95(8):3955-64.
DOI: 10.1210/jc.2010-0102 | PMID: 20534765 | PMCID: PMC2913038