Mild vitamin D deficiency may cause insomnia, weight loss and vision difficulties. However, a moderate to severe deficiency in vitamin D results in depression, weakened immune system, fatigue, osteoporosis and muscle aches and pains. Because vitamin D regulates numerous physiological operations within the body, it has been found to influence androgen activity as well. According to MuscularDevelopment.com, testosterone, a potent androgen, exhibits lower levels during wintertime when exposure to sunlight is reduced. This further correlates a relationship between low testosterone and vitamin D deficiency because vitamin D requires sunlight for synthesis.
Importance of Vitamin D
Vitamin D is actually comprised of two forms of vitamins--D3 (cholecalciferol) and D2 (ergocalciferol), both fat-soluble hormone precursors. Although the skin contains latent sources of vitamin D, humans require sunlight to activate this source, as well as additional vitamin D from either supplements or food to provide sufficient amounts for optimal health. Vitamin D is stored and metabolized in the liver where vitamin D3, which is the basic form of this vitamin, is released into the bloodstream. Because vitamin D is necessary for bone growth, skeletal muscles may cause weakness, pain, achiness, cramping and numbness. In addition, too-low levels of vitamin D may increase risk of heart disease, arthritis, diabetes and dementia in senior citizens.
Reduced Testosterone and Low Levels of Vitamin D
According to the website Musculardevelopment.com, researchers reported on a study published in the Journal of Clinical Endocrinology that investigated associations between testosterone, vitamin D and SHBG in over 2,000 males. SHBG is a compound binding testosterone in the blood resulting in inhibited interaction with receptors meant for androgens. This study found that men having optimal an vitamin D amount in their system also had higher testosterone levels but lower SHBG levels. In comparison, men who were considered vitamin D-deficient or vitamin D-insufficient had lower levels of testosterone but higher amounts of SHBG. In addition, subjects experienced reduced levels of these substances in March but peak levels in August.
Symptoms of Testosterone Deficiency
Men suffer from "low T" more frequently than women because it is such an important male hormone. Aging is generally the main cause of testosterone loss, but occasionally, medical conditions such as testicular damage or chemotherapy may lead to hypogonadism, or insufficient levels of testosterone. Symptoms of testosterone deficiency, which may be indirectly contributed to a lack of vitamin D include fatigue, depression, decreased sex drive and loss of muscle mass. This reduced muscle mass could promote pain in muscles as well, which causes older man to attribute muscle aches and pains to the aging process.
Eliminating Deficiencies in Vitamin D and Testosterone.
Taking vitamin D supplements and eating foods rich in vitamin D will rectify insufficient levels of vitamin D. Getting enough exposure to sunlight facilitates manufacturing of vitamin D also, which boosts testosterone production in the testes. According to the website Dermatology.jwatch.org, receiving a few minutes of sunlight daily to arms, neck, hands and face are all that is needed to create enough vitamin D. However, sunlight amounts vary when it comes to converting 7-dehydrocholesterol to pre-vitamin D, depending on a person's skin type and geographic location. Foods containing good amounts of vitamin D include sardines, salmon, milk, cheese, egg yolks and beef liver.
- The Merck Manual: Vitamin D
- Muscular Development: Low Vitamin D Level Lowers Testosterone Levels
- Better Medicine: Vitamin D Deficiency
- "The Journal of Endocrinology & Matabolism"; Variation in Levels of Serum Inhibin B, Testosterone, Estradiol, Luteinizing....; Anna-Maria Andersson, et al.; February, 2003
- "Clinical Endocrinology"; Association Of Vitamin D Status With Serum Androgen Levels In Men; E. Wehr, et al.; August 2010
- "Journal Watch Dermatology"; How Much Sunlight Is Equivalent to Vitamin D Supplementation?; Craig A. Elmets, MD; June 4, 2010