Can Vitamin D Restore Lower Testosterone Levels?

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Modern health folklore and bioscience state that testosterone makes you manly and Vitamin D makes your bones strong. However, recent research indicates that these two famous biomarkers have a wide variety of functions in the body and may, in fact, impact each other’s levels. Below we document some of the key reasons why you need to stay optimized in Vitamin D and testosterone, and look at the nitty-gritty research examining the fascinating relationship between them.

D is for Design: Why you Need Vitamin D

Vitamin D is an important fat-soluble nutrient naturally found in very few foods, such as mushrooms and fatty fish (i.e. sardines, salmon, mackerel) which contain high levels of vitamin D. Other foods, such as milk, are fortified with vitamin D. The body does produce high amounts of vitamin D when skin is directly exposed to sun (i.e. not through a window), so it’s sometimes referred to as the “sunshine vitamin.” However, excess sun exposure may increase the risk of skin cancer. Because vitamin D is difficult to find in foods and prolonged sun exposure carries health risks, dieticians and doctors often prescribe supplements of varying doses.

The liver first converts vitamin D to 25-hydroxyvitamin D [25(OH)D], also known as calcidiol,before it is used in the body. Blood levels of this compound are the best indicator of one’s Vitamin D status.1 The kidneys then convert this substance to 1,25-dihydroxyVitamin D [1,25(OH)2D], also known as calcitriol, before it used by the body.

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Vitamin D is typically associated with maintaining bone health and helping the body absorb minerals such as calcium and magnesium. However, recent research has revealed that this biomarker also regulates cell growth and the immune system while maintaining neuromuscular and cardiovascular health. Optimal levels of this overlooked vitamin are also crucial for athletes. Vitamin D stimulates muscle growth, increases power, and cuts unnecessary body fat.

Despite its ever-expanding catalogue of beneficial physiological functions, vitamin D deficiency is still very prevalent. In a 2011 estimate by the Centers for Disease Control, 25% of Americans were at risk for vitamin D inadequacy (serum 25(OH)D 30-49 nmol/L) and 8% were at risk for vitamin D deficiency (serum 25(OH)D less than 30 nmol/L). On the other side of the coin, excess vitamin D caused from sunlight exposure and high-dose vitamin D supplements can lead to kidney problems and nausea. 10 Some of our users, such as Laura Ingalls, experienced increased pain in joints as a result of excess vitamin D intake. When we adjust general guidelines to specific demographics and lifestyle factors, only about 14% of users have optimal levels of vitamin D. As a result, it is one of our least optimized biomarkers.

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