What is up with Vitamin D?

What is Up With Vitamin D?

The other day I was consulting with a new client (I’ll refer to her as Julie) about her recent lab work. One thing Julie had a concern about was her Vitamin D level…which was considerably low. Julie wondered how these levels could be so low since she played hours of tennis outside every day. She explained how she was out in the sun daily with only SPF 15 sunscreen. She thought she was getting enough sun…yet was she?

It seems in today’s world that everyone is deficient in Vitamin D. I live in the sunniest place on earth, San Diego, and everyone I speak with has some level of Vitamin D deficiency. Knowing we can synthesis our own Vitamin D from the sun, why are we all so deficient? Who or what is to blame about this? Is it too much sunscreen? Poor diet? Liver problems? Kidney issues? Some combination of all four factors? Let’s go deeper so we can see…What is up with Vitamin D?

What is Vitamin D?

Vitamin D is an essential nutrient obtained from food or sunlight. Vitamin D can be attained by plant sources as ergocaliciferol (D2) and animal sources as cholecalciferol (D3). Its main function is to regulate calcium and phosphorous in the bloodstream and to promote healthy bone formation. With adequate amounts of sunlight, the body can synthesize Vitamin D. By definition vitamins must be obtained by the diet since they cannot be synthesized in sufficient amounts by the organism. This makes Vitamin D unique, since it can be obtained from a source outside of food and can be synthesized by the body itself.

Vitamin D’s Function

Once Vitamin D enters the body either through food or sunlight it is transported by the blood system to the liver. The liver is where Vitamin D is converted to the prohormone (a precursor to a hormone) calcidiol. Calcidiol is then transported to the kidneys and monocyte-macrophages of the immune system where it is converted to calcitriol, the active form of Vitamin D. Calcitriol then binds with Vitamin D–binding protein (VDBP) and is transported to certain target organs.
Once at the target cells calcitriol binds to Vitamin D Receptors (VDR). This binding allows the calcitriol-VDR connection to control the flow of calcium absorption in the intestine. This is why Vitamin D is so essential for calcium absorption and healthy bone development. Low Vitamin D levels will decrease calcium absorption, which can create low blood calcium levels, which can lead to bone break down.

Who knew so many organs, proteins, enzymes and receptors where involved for the body to properly utilize Vitamin D? I bet you thought you just needed more sun…which you do. However, you also need a healthy liver, kidneys and a good diet to ensure proper Vitamin D absorption and utilization.

Why is there an epidemic of low Vitamin D levels?
To be honest, nobody knows for sure, but I can think of a few culprits that may be having an effect…

1. Liver Dysfunction. The liver plays a vital role in the conversion of Vitamin D to the prohormone Calcidiol. If the liver is overburdened with toxins (PUFA’s, drugs, alcohol, estrogen, additives, preservatives, environmental toxins, processed foods, etc.) it cannot perform optimally. Your over burdened liver spends too much time and energy trying to detox your body, thus the Vitamin D to calcidiol conversion suffers.

2. Kidney Dysfunction. The active form of Vitamin D, calcitriol is produced in the kidneys from calcidiol. Low functioning kidneys caused by renal failure or chronic kidney disease (CKD) will lead to low levels of active Vitamin D. Things that can lead to kidney dysfunction are: accidents; injuries; complications from surgeries; drug overdoses; overloads on antibiotics, aspirin, ibuprofen, and acetaminophen; chemotherapy; diabetes; and high blood pressure.

3. Sunscreen. We all know over exposure to the sun can cause skin damage and lead to skin cancer. Therefore sunscreen seems like the right answer when it comes to protecting your skin from the harmful sun’s rays. The problem is we need the sun to synthesis Vitamin D. When I was in my teens, I think the highest SPF (sun protection factor) was around 10 or 15 SPF, now it’s closer to 75 or even 100 SPF. An SPF, as low as 8, can decrease vitamin D’s absorption capacity by 95 percent. With these increased SPF sunscreens, our skin may be receiving less harmful (UVB) rays. However, these are the same rays that provide Vitamin D to our skin.
Yet the million-dollar question is…why did skin cancer incidents double from 1994 to 2006 while sunscreen sales with higher SPFs increased? Physiologist and Chemist Dr. Ray Peat’s theory is the increased level of polyunsaturated fats (PUFAs) in the diet. Stored PUFAs oxidize with heat and oxygen exposure, which can lead to skin damage, aging and cancer.

4. Diet. Although the sun is the best way to get adequate levels of vitamin D, your diet can be a contributing factor. A diet lacking in Vitamin D can lower serum D levels in the body. The best sources of Vitamin D are those found in animal products since they contain cholecalciferol (D3). Tuna, mackerel, salmon, beef liver, egg yolks and goat’s milk are good sources. D2 can also be used to increase levels of Vitamin D in the body but most research says D3 is more effective in humans. Good sources of Vitamin D2 are portabella and shiitake mushrooms and alfalfa.

Deficiency of Vitamin D
Outside of poor calcium absorption and poor bone health a deficiency in Vitamin D is linked to many other health concerns.
* Cardiovascular risks
* High blood pressure
* Multiple sclerosis
* Weight gain
* Cancer
* Fatigue
* Mental health issues
* Inflammation
* Asthma
* Poor hair health
* Diabetes

What can you do to increase your Vitamin D Levels?

1. Get more sun. Try and get at least 10-30 minutes of sun exposure between the hours of 10AM and 3PM each day. This means full body exposure, or at least show as much skin as you can. If you are sensitive to the sun or burn easily start with 5 minutes and work yourself up.

2. Avoid oils and foods high in PUFAs. Polyunsaturated fats are very unstable and oxidize quickly with heat (sun exposure) and oxygen. PUFA’s are stored in your fat tissue and when they are broken down and used as energy, they oxidize in your body causing aging, skin pigmentation, and eventually cancers. For more information on polyunsaturated fats refer to my blog, Polyunsaturated fats…Essential or toxic?

3. Eat more foods with Vitamin D3. Tuna, salmon sardines, egg yolks, goat’s milk and beef liver are good options.

4. Remove toxic and inflammatory substances. Removing or at least limiting alcohol, drugs (recreational, prescribed or over-the-counter), processed foods, fast foods, hard to digest foods, additives, carrageenan, PUFAs, estrogenic foods like soy, most grains, HFCS, and non-organic foods will help increase liver, gut and kidney function. This will encourage better Vitamin D synthesis.

5. Supplement. If all else fails take a liquid or topical Vitamin D3 supplement. The liquid or topical will absorb into your system better than a pill. I believe most pills are never a good option since they contain binders and fillers. Depending on the person, where they live, how much sun they get, time of year, and their diet, anywhere from 400IU to 10,000IU can be beneficial. Vitamin D supplements have been to shown to be incredible safe, yet Vitamin D can be toxic if levels that are too high for the individual. Most research states these are levels higher than 40,000IU.

At the end of the day we need to make sure we get adequate levels of Vitamin D into our body. Whether you choose the sun, food or supplementation…just get it in.
If you are unsure of what your Vitamin D levels should be, ask your doctor for a simple blood test. A person’s whose level is under 32 ng/ml is in need of more sun, more Vitamin D foods, or a supplement. Optimal levels are 40-50 ng/ml.

Your Optimal Health Coach,

“Disclaimer: I am an exercise physiologist, personal trainer, nutritional and lifestyle coach, not a medical doctor. I do not diagnose, prescribe for, treat or claim to prevent, mitigate or cure any human disease or physical problem. I do not provide diagnosis, care treatment or rehabilitation of individuals, nor apply medical, mental health or human development principles. I do not prescribe prescription drugs nor do I tell you to discontinue them. I provide physical and dietary suggestions to improve health and wellness and to nourish and support normal function and structure of the body. If you suspect any disease please consult your physician.”


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