What Exactly Is Vitamin D?


Vitamin D is actual a term for multiple different molecules that are created in the body from exposure to sunlight. Each form of vitamin D is basically a different step in creating the final active form of vitamin D. For people who do not supplement with vitamin D, sunlight exposure is the primary source of their vitamin D levels. The sun produces both UVA and UVB rays. It is the UVB rays, with wavelengths of 290 to 315 nanometers, that stimulates the cascade to ultimately produce the active form of vitamin D3.

When the sunlight hits the keratinocyte cells in the epidermis (outer lay of the skin), the precursor to vitamin D3 (cholecalciferol) is created from a cholesterol molecule (7-dehydrocholesterol). This precursor (cholecalciferol) enters the blood stream and is transported to the liver. In the liver, cholecalciferol is hydroxylated to form calcidiol (25-hydroxyvitamin D3). This is the major circulating form of vitamin D, and is the form that should be checked for on a blood test. However, this is not the final, active form. 25-hydroxyvitamin D3 must then go to the kidneys to acquire a final pair of oxygen and hydrogen molecules to becomes calcitriol (1,25-dihydroxyvitamin D3).

All of this may sound confusing. The number 1 and 25 just indicate the carbon number in the chair that became hydroxylated. For the purpose of this article, it is technically correct to use vitamin D as a blanket term, but background information is always good to have.

The Difference Between UVA and UVB Rays

Vitamin D

Vitamin D is one of the most profound, essential nutrients in the human body, responsible for countless critical functions. Research continues to show that there is no way for humans to acquire enough vitamin D through their food alone. In fact, the only foods that contain a decent amount of vitamin D (that are not artificially fortified like cereal) are egg yolks, fatty fish, and grass-fed beef. Even with a diet high in those three foods, our vitamin D levels would still be lower than they should. That means we either have to obtain the vitamin D through supplementation or through exposure to sunlight.

Large amounts of vitamin D3 is made in the skin when it is exposed to sunlight for a period of time. The creation of D3 happens at a different rate for every person. The nice part is that for every person, their skin will produce vitamin D in approximately half the time it would take their particular skin to burn. So, the goal is to expose the skin long enough to get in the nourishing sunlight, but not long enough for the skin to burn. For a fair skinned person, that might be only 10 minutes. For a darker skinner person, they might be able to stay in the sun for over an hour without burning.

You don’t need to tan or to burn your skin in order to get the vitamin D you need. Exposing your skin for a short time will make all the vitamin D your body can produce in one day. In fact, your body can produce 10,000 to 25,000 IU of vitamin D in just a little under the time it takes for your skin to turn pink. You make the most vitamin D when you expose a large area of your skin, such as your back, rather than a small area such as your face or arms.

    The amount of vitamin D you get from exposing your bare skin to the sun depends on:

  • The time of day: your skin produces more vitamin D if you expose it during the middle of the day (usually between 11 and 2). This is because earlier and later in the day, the sun rays ever the Earth’s atmosphere at too much of an angle, blocking the UVB part of the rays. A fun guide is looking at your shadow. If your shadow is longer than you are tall, than you are most likely not producing any vitamin D.
  • The time of year: here in the northeast, we can only produce vitamin D from the sun during the summer months (or about half the year). All winter long, no matter how much skin you have exposed to the sunlight, there will be no vitamin D production. This has to do again with he angle of the Earth, and the amount of UVB rays getting through the atmosphere. This is why we have seasonal affective disorder (SAD). Most people have their vitamin D levels plummet by over 50% during the winter months.
  • Where you live: the closer you live to the equator, the more months of the year you will be abel to produce vitamin D from the sun. Even residents of Florida will be able to utilize UVB rays for about 9 out of 12 months instead of the 6 we have further north.
  • The amount of skin you expose: the more skin your expose the more sunlight you will take in, and the more vitamin D your body will produce. Laying on the beach with an exposed back would yield more vitamin D than working in the garden with just exposed forearms.
  • The color of your skin: pale skins make vitamin D more quickly than darker skins. This is because the melanin, the substance responsible for tanning and affecting how light or dark your skin is naturally protective against burning from the sun rays. While darker skins may be at an advantage in the length of time they can stay in the sun without burning, it also means it will take them longer for their skin to get enough sunlight to produce vitamin D. (see chart to the right)
    • There are other factors which can affect the amount of vitamin D your body makes from exposure to the sun. These are:

    • Age: The older you are, the harder time your skin has producing vitamin D.
    • Sunscreen: The “protective” nature of the sunscreen will also block the beneficial aspects of sunlight exposure.
    • Clouds: On a cloudy day, less UVB rays will reach your skin.
    • Glass: Being behind glass like in a car or inside a building will block the UVB rays so you can’t make vitamin D.
    • Pollution: Air pollution will also filer out the UVB rays you need to make vitamin D.
    • Altitude: The higher up you are, the closer to the sun, and the less time it will take the skin to produce vitamin D.

    CAREFUL: When these above things block or filter out the vitamin D producing UVB rays, the more harmful UVA rays still get through. So, you can still burn, causing skin damage on cloudy days and behind glass.

    Trovato Nutrition is not a tanning salon, but we do have one specialized tanning bed that is available for use. While this bed will provide the skin with a nice tan, it does so much more than just superficial tanning!

    The Mercola Vitality Tanning Bed has more than just that standard UVA bulbs that are common in normal tanning salons. Our vitamin D tanning bed has UVA, UVB, and Infrared, bulbs, each included for a specific function.

    UVA and UVB Lamps

    Ultraviolet A rays are the rays that produce a tan, naturally protect your body from sunburn, and balance your body’s synthesis of vitamin D.

    Ultraviolet B rays help your body produce the vitamin D necessary to health and well-being. Studies suggest vitamin D levels drop an average of 50% in winter months. Your body needs vitamin D for healthy skin and healthy immune and cardiovascular systems, and it also protects prostate health for males.

      Infrared light penetrates deeper tissues:

    • Temporarily relieves muscle and joint soreness/stiffness
    • Provides a comforting feeling of penetrating warmth
    • Stimulates blood flow and circulation
    • Up-regulates metabolism
    • The bed also contains specialized red and blue lights in the face region that promote natural skin rejuvenation.
    • Red light produces a 633 nm wavelength:
    • Improves skin texture, hydration, and tone
    • Helps reverse signs of aging by naturally stimulating your skin to produce collagen, elastin, and skin-supportive enzymes
    • Benefits acne, age spots, and other skin disorders
      Blue light produces a 417-419 nm wavelength:

    • Supports overall skin health and complexion

    The Mercola Vitality Tanning Bed also is different from the many salon tanning beds that emit an electromagnetic field from the magnetic bulb ballasts as well as x-rays from the bulb ends. The loud hum of salon tanning beds characterizes these EMF producing ballasts.

    The Mercola Vitality Bed features an electronic ballast that virtually eliminates EMF radiation.

    To learn more about the benefits of vitamin D tanning beds, call Trovato Nutrition at (215) 293-0909 today.