Sun Safely: Maximize vitamin D absorption while protecting yourself from sun damage - Aviva Allen's Blog

Sun Safely: Maximize vitamin D absorption while protecting yourself from sun damage

Posted by on in General
  • Font size: Larger Smaller
  • Hits: 8430
  • Print

The sun has finally started shining and it's time to get outside and enjoy it!  At the same time, we also need to think about protecting our skin from harmful UV rays.  Most of us know about the importance of sun protection, but many are now becoming concerned about vitamin D levels when sunscreen is applied at all times. 

How do we find the right balance of vitamin D absorption and UV protection?

Simply taking a vitamin D supplement is certainly an option, however, if you are interested in obtaining vitamin D naturally from the sun, here is some information that will help you do that safely.  

Maximizing vitamin D absorption from the sun

Season, time of day, cloud cover, smog, skin colour and the use of sunscreen are among some of the factors that affect vitamin D synthesis. The combination of these factors can make it difficult to determine the necessary length of sun exposure time for a particular individual to produce optimal levels of vitamin D.  It has been suggested by some vitamin D researchers that approximately 15-30 minutes of midday sun exposure, of at least 15% of the body,  at least twice a week without sunscreen, would usually lead to sufficient vitamin D synthesis. The more skin exposed, the shorter the length of time required.  A darker-skinned individual, however, can require up to six times the amount of exposure to produce the same amount of vitamin D as a fair-skinned person.

Your best source for vitamin D is daily exposure to the sun, without sunblock on your skin, ONLY until your skin turns the lightest shade of pink.  The production of vitamin D occurs in the skin within minutes and is fully maximized before your skin turns pink, so there is no benefit to staying in the sun longer.  Longer exposures will not produce any more vitamin D but WILL accelerate photo aging and increase your risk for skin cancer.  Cover up before your skin becomes tanned or burned as both are signs of sun damage.  As our vitamin D levels increase, more melanin (pigment) is made to protect us from getting too much of the vitamin (excessive amounts can be harmful to our bodies).  The more melanin our skin has, the less vitamin D we can make.  This is why darker-skinned individuals have a more difficult time maintaining optimal levels.

To use the sun to maximize your vitamin D production and minimize your risk of skin damage, the middle of the day (roughly between 10  and 2) when the sun is at its highest, is the best and safest time for short periods of unprotected exposure. During this UVB-intense period you will need the shortest sun exposure time to produce the most vitamin D.  While this isn't always possible due to the change of the seasons and your geographic location, this is ideal as it will optimize your vitamin D levels naturally with less exposure to damaging UVA rays. 

* Note that UVB radiation does not penetrate glass, so exposure to sunshine indoors through a window would not produce vitamin D.  Also note that wearing sunscreen will block vitamin D-producing UV rays.

Other Sources of Vitamin D

Individuals with limited sun exposure should include good sources of vitamin D in their diet and/or take a supplement to achieve recommended levels of intake.  Supplemental vitamin D should also be taken during the winter months (October-April) as we do not receive enough sun in this part of the world to obtain sufficient amounts naturally.  Vitamin D is naturally present in very few foods. The best sources would be cod liver oil or fatty fish such as salmon, tuna, and mackerel.  Small amounts of vitamin D can also be found in beef liver, cheese, and egg yolks.

Tips for protecting your skin from sun damage

  • The use of indoor tanning beds may increase a person’s risk of developing skin cancer.  The CDA, along with Health Canada and the World Health Organization (WHO), strongly recommend that tanning beds not be used.
  • Avoid over-exposure to the sun during the midday hours of 11-4 as this is when UV rays are the strongest
  • Use a broad spectrum sunscreen formula with an SPF of 30 or higher when spending more than 30 minutes outdoors. (Note: SPF numbers only tell you the amount UVB protection that is offered.  UVB rays are what cause tanning and burning.  Using a sunscreen with a higher SPF that does not offer sufficient UVA protection, would allow you to stay out in the sun for longer periods of time without burning, while allowing more of the damaging UVA rays to penetrate your skin.)
  • Apply sunscreen 20 minutes before exposure, re-apply after every 2 hours of sun exposure and re-apply after swimming (even if using a water-resistant/waterproof formula).
  • Cover up with a wide brimmed hat, sunglasses.
  • Keep infants under 6 months away from direct sunlight.  Protect children over the age of 6 months with natural sunscreens, hats and UV protective clothing.


Aviva’s pick for sunscreen:

I recommend choosing a natural sunscreen that uses zinc oxide as the active ingredient.  Zinc oxide provides excellent UVB and UVA protection and is a safer alternative to chemical sunscreens.  I love Green Beaver SPF 30 sunscreen!  It's a Canadian company that is certified organic, Health Canada approved, non-whitening, waterproof, fragrance-free AND easy to apply, which is essential when you've got squirmy kids that won't stand still for very long.

Aviva Allen is one of Toronto's leading Kids' Nutritionists specializing in helping parents deal with their picky eaters. Inspired by her two young boys' adventures in food, Aviva helps children and their families establish healthy eating habits through her nutritional counselling, offering consultations via phone or Skype. Aviva is also the founder of Healthy Moms Toronto, helping connect like-minded moms throughout the GTA.