Vitamin D – The Supplement That is a Hormone
Vitamin D is an excellent supplement but also works in the body primarily as a hormone. It is a steroid hormone that is generated in the skin via sun exposure from cholesterol. Vitamin D may also be supplied by food and by supplementation. Vitamin D has multiple positive effects on the body similar to the other hormones that we have discussed. Vitamin D plays a significant role in bone health by increasing the intestinal absorption of calcium, magnesium, and phosphate. It also promotes the healthy growth and remodeling of bone as optimal levels of Vitamin D are paramount to the proactive and reactive treatments for these disorders. It also allows for proper functioning of parathyroid hormone which helps to maintain ideal levels of calcium in the blood. Vitamin D works to maintain muscle size, strength, and function via minimizing sarcopenia and muscle atrophy. This also has the benefit of reducing falls and the resulting trauma and disability that may occur. It is also helpful in improving overactive bladder, pulmonary function, macular degeneration, and cognitive decline.
It has also been shown to decrease the risk of breast, colorectal, ovarian, renal, pancreatic, and prostate cancer. High/ optimal levels of vitamin D have been associated with a substantial decrease in cardiovascular disease, diabetes mellitus (type II), and metabolic syndrome. Vitamin D treatment also provides a benefit for depression and reduces all-cause mortality by 7%. Optimal levels have also been shown to combat and treat the deleterious effects of autoimmune diseases such as rheumatoid arthritis, SLE, Crohn’s disease, ulcerative colitis, leaky gut, Hashimoto’s thyroiditis, diabetes mellitus, eczema, and Alzheimer’s dementia (described as diabetes mellitus Type III).
Vitamin D comes in two supplemental forms. The first is ergocalciferol or Vitamin D2 which is metabolized to 25-hydroxyergocalciferol. The second is cholecalciferol which is Vitamin D3. This form is metabolized in the liver to calcifediol (25-hydroxycholecalciferol). These two metabolites call 25-hydroxyvitamin D or 25(OH)D. These levels are measured via blood work to determine the Vitamin D level. Calcifediol is further hydroxylated in the kidneys to form calcitriol (1,25-dihydroxycholecalciferol) which is the biologically active form of Vitamin D. Typical doses for optimization are 5,000 to 10,000 international units per day. The body may formulate Vitamin D from 7-dehydrocholesterol from reaction via UVB radiation via the sun. Exposure to the sun for 5-10 minutes upwards of 2-3 times per week (without sunscreen) typically is sufficient for optimal Vitamin D levels. Food sources of Vitamin D include cod liver oil, herring, swordfish, mushrooms, sardines, tuna, fortified milk, and eggs. Ideal levels range from 60-100 nmol/L. Levels above 100 may become necessary for patients with severe deficiency and rarely cause side effects.
Symptoms of Vitamin D deficiency include frequent illness and/or infection due to immune system suppression, fatigue, bone pain, mental health issues, impaired wound healing, hair loss, and myofascial pain. These are common problems that afflict patients that I assess on a daily basis. Chronic deficiency of Vitamin D may result in obesity, diabetes, hypertension, depression fibromyalgia, chronic fatigue syndrome, osteoporosis, and neurodegenerative disorders. For example, patients with diffuse muscle pain/fibromyalgia respond well to Vitamin D optimization (as well as thyroid, growth hormone, and testosterone maximization). Impaired wound healing and hair loss may also be treated by PRP injections (discussed previously) along with Vitamin D. These examples thus illustrate the theme expressed throughout the pages in this book that treatment plans are multifactorial and typically require time to fully manage the problem. This conforms with my overall philosophy that everything matters and is intertwined in the fabric of disease and dysfunction. Therefore, knowledge is power for both myself and the patient and my education has ultimately provided a plethora of tools and options for management.