|Each year, thousands of San Diegans, 'Zonies, and
other tourists take full advantage of the local sunshine to either romp or
vegetate under the sun. Even "natives", however, often fail to
appreciate that San Diego is, in actuality, a desert (albeit an irrigated
one) and this poses some definite risks to sun worshippers. In this issue,
we'll discuss some tips on safety in the heat.
The sun is a source of different types of energies, particularly heat
and light, each associated with their own potential problems for us mere
Light can be broken down into "spectrums" or groups of
various wavelengths, some of which we can see (so-called "visible
light" e.g. colors of the rainbow) and some which we cannot (e.g.
x-rays, ultraviolet, etc.). Ultraviolet light can be further subdivided
into frequencies that we term ultraviolet A ( UVA) and
ultraviolet B (UVB).
UVB is the one that has gotten most of the attention over the past years
because it is the primary reason for sunburn reactions, while UVA is being
more recognized as important to the wrinkling /aging process.
Although the use of sunscreens is finally reaching acceptance, up until
the few years or so, commercially available sunscreens only offered
protection against UVB and not UVA. Still, any protection was better than
none - especially with regards to the prevention of the various skin
cancers such as basal cell carcinoma and malignant melanomas. The newer
sunscreens (such as Photoplex), fortunately, do offer protection
against both UVA and UVB rays.
Be sure to select a sunscreen/sun block
that has a SPF (sun protection factor) of at least 15.
Note that this
does not represent an absolute number of minutes that you can spend in the
sun. Rather, it is a relative number - you can stay out 15 times as long
with an SPF of 15, than you can with an SPF of 1, before your skin burns.
For example, if you can stay out only 10 minutes using a sun block SPF 1
before burning, than you can stay out approximately 150 minutes using one
with an SPF 15. Bear in mind that there are other factors to consider as
well. You should try to avoid the most intense of the sun's rays in the
afternoon - sun block will offer longer protection earlier or later in the
day when the sun is not directly overhead. Also, be sure to apply enough
sunscreen to do the job properly - most people do not apply adequate
amounts - and to reapply as often as needed, especially after swimming or
Get in the habit of applying sunscreen, at least to your
face, every morning when you brush your teeth. Be sure to include the back
of the neck and ears, as well. (If you drive for a living, consider
applying sunscreen to your left/window arm too!) In the long run, sun screening
not only extend protection against skin cancers, but will help to decrease
the amount of wrinkling as you age!
Speaking of sweating, this is just one of the ways that your body cools
itself down to avoid overheating. Overheating of your brain leads to all
sorts of "nice" conditions ranging from simple heat intolerance
to the life threatening heat stroke.
Prevention is the key to the treatment of heat-related illnesses.
can avoid the excitement of receiving intravenous fluids and ice water
baths with just a bit of forethought. The key here is adequate hydration
prior to your activities and maintaining it through their duration. This
applies whether you are sunbathing on the beach or playing a few hard sets
of volleyball (the only difference may be in the amount of fluid needed to
You should ideally begin the day before by drinking as much of your
favorite fluid (not alcohol!) as you can tolerate (you'll know you've had
enough when your pee is clear!). Then, before your "event",
drink two 8 ounce glasses of fluid approximately 20 minutes prior to the
start. As the game or activity continues, you should plan on drinking 8
ounces of fluid about every 20 minutes or so, depending upon the activity
and your intensity, until you finish. If you're feeling fatigued, increase
your fluid intake.
What is the ideal replacement fluid? For activities lasting less
than one hour, there is no benefit to anything more expensive than plain
water. Activities lasting longer and associated with heavy or steady
loss of body fluids through sweat and dehydration may benefit from one of
the commercially available rehydration solutions (e.g. Gatorade, Exceed,
etc.) which contain electrolytes (sodium, potassium) and 4-6% sugar for
calories. (Regular fruit juice has a sugar concentration that is too high
for replacement in an athletic event and this will slow emptying of the
stomach. Diluting it by half with water, however, is a reasonable
alternative.) Experiment with the various brands to see which one tastes
best to you (read: most tolerable) and stick with the one with
which you feel the most comfortable.
Alcohol can lead to further
dehydration, therefore, itís best avoided!
Don't forget to increase your salt intake under hot
weather conditions (unless your doctor has told you otherwise), along with your
Most of us have had it well-drilled into our heads about the importance of
drinking plenty of fluids in order to avoid dehydration under these
circumstances. However, it's possible to run into other potentially deadly
medical problems if one only consumes plain water, particularly lots of it.
Our bodies produce sweat as a cooling mechanism in hot weather. The evaporation
of the sweat from off of our bodies is what cools us down. Sweat contains both
salt (sodium) and water. Drinking lots of plain water replenishes the fluid
losses, but - at the same time - serves to dilute the already diminished sodium
stores that remain in the body. This results in a condition known as
When the sodium concentration in our blood drops just a little lower than
normal, we might feel some nausea, fatigue, and "just don't feel right." If
it continues to drop, dizziness develops and this may be accompanied by
muscle cramps and vomiting. If the serum sodium drops too low, victims can
experience seizures, go into a coma, and even die!
So, how to avoid this problem?
If you're only going to need a few sips of liquid, then water is fine. However,
if you need to drink lots of fluid, particularly over a period of greater than 1
1/2 hours, then a better choice of fluid replacement would be one of the
electrolyte sports drinks such as Gatorade or Powerade. Be aware that these
drinks may not fully replace the lost sodium, either, but they're much
better/safer than plain ol' cold water under these circumstances.
Another option: Keep a few of those small salt packets handy (e.g. from your
favorite fast food restaurant - no lectures on that today...) and open the
contents of one into the palm of your hand and lick all of the salt off. As
little as 2 or 3 packets per day can help to maintain the serum sodium level up
to where it should be. Also, unless your doctor has cautioned you against this,
be more liberal with the use of a salt shaker with your meals under these hot
Does this strategy work? Yes, definitely. This has been a problem that we had
noted in our runners for a while, particularly under warm race conditions.
(Inexperienced runners tend to believe that they must drink water at every water
Also, we tend to see more high school and college football athletes cramp up
during games under hot weather conditions. Somewhere along the way, smart
athletic trainers discovered that providing pickle juice to their players helped
to cut down on the frequency and intensity of the cramping. (You'll have to
trust me that Gatorade or licking salt straight off of your hand tastes a whole
lot better than pickle juice.)
Broad-brimmed hats, long sleeves, and long slacks or
skirts offer protection (a baseball cap offers SPF 5 protection for the
forehead.) A T-shirt or thin cover-up is probably not very effective,
however, especially if itís made of gauzy, loosely-woven material.
some medications can cause problems when used in the sun or heat!!!
Certain antibiotics (sulfonamides, doxycycline. etc.), diuretics (furosemide),
acne meds (Accutane, Retin A) , as well as some soaps and perfumes can
cause a photosensitivity reaction in some people. This may occur as an
exaggerated sunburn or rash on an exposed area.
Also, individuals taking certain antipsychotic medications such
as Thorazine and Haldol can develop a malignant hyperthermia syndrome
and die from it. Consult your physician if you have any
Jeffrey Pearson, D.O. (1995)