Everyone that follows health now-a-days has already learned that the new studies about the importance of Vitamin D as a part of your daily health needs is an absolute must. And, for the most part, all the research shows that a person can get all the healthy Vitamin D they need from … are you ready for this? … sunlight! Yup! When it comes to manufacturing Vitamin D in your body, there is nothing quite as good as a sunny day and about 20 minutes in the sun.
So, how does this work? It’s really very cool how G-d makes it happen. Most of us know that there are three kinds of different ultraviolet (UV) rays – ray that come in different lengths: UV-A, UV-B, and UV-C.
The UV-B rays are the ones capable of producing vitamin D in our body. In a nut shell, it acts on the cholesterol found in our skin. To make vitamin D, we need UV-B rays to come into direct contact with our skin. When I say direct, I mean to say that you can’t sit in front of a window and get the ‘rays’ you need. UV-B rays can’t penetrate glass. You are going to have to get outside to catch this good stuff.
There are a number of factors that determine how much vitamin D (by the way, vitamin D is really a form of steroid and not an actual vitamin) you get from the sun, i.i. the number of minutes of exposure your body needs to get the UV-B rays enough to do the job. Among some of the obvious factors, the time of year. If it’s winter, you are going to need more exposure. Likewise, the further north or south of the equator, the more sunlight you will need. And of course, polution and clouds (a no brainer). But, the two biggest factors are:
Your Age. As you get older, your skin loses its ability to convert convert cholesterol in your skin into vitamin D from UV-B rays. If you are older, you probably want to rely more on food sources than sunlight for your vitamin D, since someone, let’s say at 70 years old has only 30% of the capacity to generate vitamin D from sunlight as that of a 20-year old.
Your Skin Color. If you have a light complexion, you have a much greater ability to absorb UV-B rays, thus needing less exposure to the sun to get adequate vitamin D production. The darker your skin, the harder for UV-B rays to absorb into your skin and create vitamin D.
As the evidence comes in on this, doctors are lamenting the fact that more people will be getting healthier now that they have a green flag to get out in the sun and not be so afraid of it. The growing mountain of evidence indicates that your body getting enough vitamin D is essential to reducing the risk of almost every disease out there that most people fear. Here are a partial list of them where vitamin D deficiency is linked to increased risk:
- Osteoporosis. [see footnote 4,5]
- Multiple sclerosis, rheumatoid arthritis, and other autoimmune illnesses. [see footnote 7,8,9,10]
- Colds, flus, and other infectious diseases like tuberculosis.
- Cancers of the breast, ovary, prostate, colon, esophagus, pancreas, and leukemia. A study published in the American Journal of Clinical Medicine in 2007 found that women who ingested 1,100 IUs of vitamin D and 1200 mg of calcium daily
- reduced their risk of developing cancer by 70%. [see footnote 1]
- Rickets, which occurs at about six months of age in children who are vitamin D deficient. Presenting signs are typically skeletal deformities, growth retardation, and muscle weakness. [see footnote 12]
- Diabetes types 1 and 2. [see footnote 2,3]
- Osteomalacia – chief complaint is typically generalized aches and pains throughout muscles and bones, often misdiagnosed as fibromyalgia or chronic fatigue syndrome. [see footnote 6]
OK, so, before you run out and lay naked in the sun trying to cure all your ailments and diseases, it is important that you also understand that with added exposure to the sun comes some ‘undesirable effects’ like premature aging of skin and increased risk of non-melanoma skin cancers, SOOO I would recommend that you do some of your own research, use wisdom in your day to day life in seeing that you are eating the right foods, and getting a little more sun than you normally do if you are not an avid sun worshipper.
As a general rule, you can typically know when you have gotten too much sun when you have been out long enough to start feeling your skin having a little extra warmth to it – typically just about the time you are seeing a little pink showing up on your skin. It’s that look and feel of, “hmmm… I think I need to get out of the sun. I am feeling like I may be getting burned,” look and feel. Ideally, you want to shoot for exposing your body for about 30% to 50% of the time that represents your feeling like you are getting burned. For days when you have to be under the sun for longer than about half of your minimal erythemal dose, once you get to this point, you can use protective clothing and hats or a good NON-toxic sunscreen to keep from getting burned.
Are You Deficient?
How do you know if you are getting your daily needed dose of vitamin D? Well, the easiest way is to have your blood tested for 25 hydroxy D. If you’re below 50 ng/ml, you can get more vitamin D through sunlight and/or take a vitamin D supplement.
If you live in the subtropics or tropics and you aren’t shy about getting sunlight exposure, chances are that you don’t need to take a vitamin D supplement. And, if you are indoors quite a lot, tend to stay out of the sun, and/or live in the mid or high latitudes, chances are good that you can benefit from vitamin D supplementation.
- Seventy-six percent of pregnant women were found to be severely deficient in vitamin D.
- Eighty-one percent of babies born to women who were vitamin D deficient were deficient themselves, predisposing them to diabetes type 1, multiple sclerosis, schizophrenia, rickets, and a number of other diseases.
- Thirty-two percent of physicians and medical students were vitamin D deficient.
- Up to sixty percent of all hospital patients and eighty percent of nursing home residents are D deficient.
- Forty-two percent of African American women of childbearing age were D deficient.
- Close to fifty percent of girls between 9 and 11 years of age were vitamin D deficient.
And, ONE BIG LAST POINT for now: If you are fat, you most likely need to get more vitamin D than someone who is not fat, since obesity is a risk factor for vitamin D deficiency. It’s because vitamin D gets trapped in fat tissue and has difficulty entering your bloodstream to supply your cells. This means that on the average, someone who is over weight needs twice as much vitamin D as somoene who is not fat order to maintain optimal vitamin D status. 
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