We are all solar powered to some extent.  While we derive our physical energy from food, sun is a critical part of our development and well-being.  Imagine how you feel after a long, gloomy, overcast winter.  Now imagine a child developing their sense of emotional well-being during such a climate.  Humans used to spend virtually all of our days outside when we lived in the wild, and now that we’re industrialized we spend most of it indoors.  Even when we do go outside these days, we’re fully clothed.  Add to this the need to protect ourselves against skin cancer, and suddenly we’re spending our lives in the shade.  So our sunlight exposure has undergone a dramatic shift, and we’re only beginning to understand the consequences of this on our health.  Is skin cancer a real risk?  Absolutely, and in fact children are the most vulnerable to DNA damage from UV rays as you will see.  So having a healthy relationship with the sun is important, and it’s about finding the right balance.

Vitamin D is one critical human need that is met by sunlight - it needs to be converted into its active form by the sun’s rays.  It’s most obvious effect is in regulating our calcium metabolism.  Without vitamin D, our bones don’t mineralize well, causing rickets.  Rickets sucks.  But we are now learning that rickets is just the tip of the iceberg.  New research is coming out linking vitamin D deficiency to all sorts of other things:  cancer, autoimmune disease, autism and mental illness, to name a few.

What about vitamin D supplements?  In an ideal world, we would get just the right amount of sunlight, and therefore the right amount of vitamin D.  In reality, however, children in Portland, even those who play outside all the time, are typically deficient simply because the sun is too low in the sky to be strong enough to make the conversion to vitamin D in our bodies.  So apart from the middle of summer, a supplement is essential.  There are differing opinions about how much is needed, but using the chart below is a good bet for now. 

Some sources, including the vitamin D council, recommend considerably more than this, last time I checked.  They may be right, but they could just as easily be wrong, and until the safety data is fully out I’m just a little nervous recommending high doses as this could be harmful.  In patients of mine who take their supplements regularly, the doses in the chart above have led to good blood levels.  In patients who frequently forget their doses, even those who get out in the sun, the levels have been below where I like to see them.  So just try to remember the supplement every day, and know that it’s very much OK to double up on your dose if you forgot to take it the day before, whether for an infant or an adult.  If you average the above doses, and get some *safe* sun exposure, you will likely be in good shape. 

What about skin cancer?  Skin cancer is a very real risk, and one to take seriously.  However, excessive fear of skin cancer may lead to health problems as well.  Consider how many people spend less time in the sun, leading to less exercise, worsening mood, and vitamin D deficiency with all of its associated diseases (other cancers, autoimmune diseases, autism?).  Nonetheless, sunburn is incredibly harmful to the skin and should be strictly avoided at ALL COSTS.  In fact, a single sunburn in childhood may as much as double a child’s lifetime risk of skin cancer.  Because risk multiplies, burn just a handful of times in childhood and their risk goes off the charts.  Why would this be the case?  First off, children’s skin is thinner and less protective against DNA damage. Second, they spend more time outdoors.  And third, they are young, so any small DNA mutations have decades and decades of time in which to become cancerous.  When we lived in the wild under the sun, our life expectancy was not long enough to get much skin cancer, so it wasn’t an issue.  But now that we’ve doubled our life expectancy, there is ample time for that early damage to become later problems - we need our skin to stay healthy for 80 years!

It seems like such a Catch-22, you get one kind of cancer with too much sun, and other kinds of problems with too little sun.  Isn’t there a happy medium?  I like to think so. 

Summer tips:

1. Spend as much time outdoors as possible, it’s good for you!
   

2. Learn how much sun your child can tolerate and always proceed cautiously.  Start small, and gradually increase to make sure they don’t burn, watching them closely.  Skin will often turn slightly red temporarily prior to burning, this is a sign that you are dangerously close to a sunburn, so take note as well as immediate action.  As the summer goes on they may get some color and tolerate more sun without burning.  There is no set minute amount because it is different for different children.  Almost all kids can tolerate 10-15 minutes safely, many can tolerate more.
   

3. During the “sunshine gathering” part of their outdoors time, go ahead and have as much skin exposed to the sun as possible, just do it for less time.  More surface area exposed means less sun needed per square inch to produce the same amount of vitamin D for the body.  This means less burning, more vitamin D.  Smart, huh?  Just remember to watch and not forget to protect them after a few minutes in the sun.  Set a timer.  Is setting a timer excessive?  Nope!  Would you set a timer to avoid burning your turkey?  I would argue that kids are at least as important as turkeys...
   

4. After your child has been in the sun a bit but before the danger of burning comes, cover them with clothing and/or shade.  Apply sunblock only on the parts that can’t be covered, and make sure to use a gentle, fragrance-free variety (always check the 2011 sunscreen guide from the cosmetics database before purchase).  Applying sunblock will completely block their vitamin D production, but if they get a couple minutes of sun before you apply then they should get their dose safely.
   

5. Note your child’s skin tone.  The highest risk children for skin cancer are red heads, lowest risk are dark-skinned children.  This also means that darker-skinned children need to work harder to get vitamin D, and may benefit from vitamin D supplements even in the summer.  Also consider the supplement in summer for red heads because they are so sensitive to the sun and may not be able to get enough vitamin D before burning.
   

Spring and Fall tips:

1. Continue to spend as much time outside as possible, with skin exposure as permitted by weather/temperature.
   

2. Your child can likely spend more time in the sun during these times without burning, but still be careful about burns, they still happen!
   

3. Take your vitamin D supplement, even when the sun is shining.  It is so low in the sky during these seasons that it is likely not enough to keep up your vitamin D levels. 
   

Winter tips:

1. Continue to spend as much time outdoors as possible.  Though there will be no vitamin D production clothing or not, it’s still good to get out there and stay active.
   

2. Take your vitamin D supplements!  Try not to forget, but if you do, double up.
   

3. While some people use tanning beds, which can give some vitamin D production, I do not recommend them because they are an unnatural source and may dramatically increase skin cancer risk.
   

4. However, take a winter trip to Caribbean!  And while you’re at it, take your pediatrician along with you...