Sunlight & Vitamin D

We've talked about the importance of sunshine in a previous article but we came across new, supplementing and interesting data from Dr. M. F. Holick, Ph.D., M.D. He's a Professor of Medicine, Physiology and Biophysics; a Director of the General Clinical Research Unit; and a Director of the Bone Health Care Clinic and the Director of the Heliotherapy, Light, and Skin Research Center at Boston University Medical Center. He's done extensive research on Vitamin D. He determined the mechanism for how vitamin D is synthesized in the skin, demonstrated the effects of aging, obesity, latitude, seasonal change, sunscreen use, skin pigmentation, and clothing on this vital cutaneous process. (Source: Dr. Holick's website - link below)

Here is the fantastic info from an interview with Dr. Holick about sunlight and vitamin D. Reasonable sun exposure provides health benefits not obtained via vitamin D supplementation. It reduces risk of: melanoma, all cause mortality, breast cancer, blood pressure, MS, obesity & Type II Diabetes. It increases the risk of: non-melanoma skin cancer.

Health benefits associated with sun exposure that you do not get from solely supplementing with vitamin D:

• When exposed to sunlight, you produce beta endorphin, this is what makes people “feel better” in the sunlight.
•  When exposed to sunlight, you make nitric oxide, which is a natural way of reducing blood pressure.  This results in feeling more relaxed.
• A whole host of other important biochemicals in your skin that may be important for your health.

Could some of this be tied to living in a blue zone/green zone?

• Earlier studies in 1915 showed that outdoor workers had significantly less risk of dying of cancer than indoor workers.
• This was followed up in 1940 by Dr. Apperly who showed that if you lived in the Northeast you are more likely to die of cancer than if you lived down South.

Is it better to shoot for optimum sun exposure, optimum vitamin D levels, or both?

• Both. Use D Minder app for sun exposure + 5-6,000 IU of vitamin D per day
• Can’t do it with sun alone, can’t do with vitamin D supplementation alone

Note about Sunscreen

• An SPF of 30 put on properly, has been shown to reduce ability to make vitamin D in your skin by about 95%

Note about Vitamin D supplement

• 5000-6000 units of vitamin D every day no matter the season

Dr. Holick’s recommendations for ideal levels of vitamin D

• Minimum 30 ng/ml, however 40-60 ng/ml is ideal. Max 100. Over 150 - 200 is dangerous

 
Dr. Holick’s guidelines for obtaining adequate sun exposure

• Obtain unprotected, non-burning, sun exposure
• Use sun block on back of hands and face

What to do in the winter?

• As our ancestors were migrating north and south of the Equator vitamin D was stored in their body fat
• The half life is about two to three weeks. Meaning you could get through winter and still be vitamin D sufficient if you’re starting out at a level of 60
• If you get your level around 40 to 60, there will be minimum fluctuation in your blood levels as long as you continue to take that 5000 units of vitamin D every day because the higher your blood level, the less variation and change in your 25-hydroxy vitamin D for either an increased dose or lack of sun exposure

What about tanning beds?

• Don't use tanning beds
• One study found increased risk of all cause mortality and cancer death
• Certain “safe” tanning beds (UVA and no UVB) are worse for your health – there's no vitamin D and you are damaging your skin
• If it's putting out a lot of UVB you should be in that bed for a shorter time (half the time ideally)
• Always protect your face

What about people with malabsorption issues?

• “Highly absorbable” forms of vitamin D (liposomal, micellized, creams) don't have any evidence showing they work
• 50% of the tanning time, always protect your face.

Dermatology community

• Opinions here are changing – the world health organization now recommends getting sensible sun exposure.
• There was a paper published in 2003 in the Journal of Investigative Dermatology. Kennedy is the first author. He concluded that “occupational sun exposure reduces your risk for developing the most deadly skin cancer, malignant melanoma.”

Sources:
Learn more about Dr. Holick - click here

---

UCSD Video with Dr. Holick