By Dr Nina Radcliff
We light up the skies with spectacular fireworks across our nation in
celebration of the Fourth of July, our country’s birthday. On that day
in 1776, the members of the Second Continental Congress met in
Philadelphia to adopt the final draft of the Declaration of
Independence. John Adams predicted that, “It will be celebrated with
pomp and parade… bonfires and illuminations from one end of this
continent to the other.” What a visionary! He was so right!
As we get ready for our parades, festivals, and get-togethers, there
is an elephant in the room: the heat. Recently, it’s been so hot that
by the time I get home from the grocery store, my loaf of bread is
toast and I overheard a pig on the beach say, “I’m bacon.”
How do we “chill out?”
Our body temperature remains within the narrow range of 98.6 degrees
Farhenheit, plus or minus 1 degree. Our skin plays a pivotal role when
it comes to keeping us cool. As our internal temperature rises, blood
flow automatically increases to the upper layers of the skin so heat
can dissipate into the environment. Concurrently, water diffuses
through the skin (a.k.a. perspiration, sweating), and heat is removed
from the body when it evaporates–similar to a pan of boiling water.
Can I get a chemistry and physics refresher course?
We all know that a hot cup of coffee will cool over time (heat
dissipates into the environment), but will never become cooler than
room temperature. Heat is a form of energy and always flows from high
temperature to low temperature, a phenomenon known as equilibrium.
When the temperatures between our body and the environment are equal,
there is no net flow of heat. Consequently, hot weather makes it
difficult or impossible for us to cool down.
What can happen if we cannot cool down?
We can experience heat-related illnesses ranging from rashes to heat
cramps, exhaustion, and stroke. Heat cramps are painful spasms in our
legs and abdomen that are accompanied by heavy sweating. Heat
exhaustion describes confusion, dizziness, fainting, headache, and
vomiting. This can progress to heat stroke, a medical emergency, where
our body’s temperature increases to greater than 105 degrees
Fahrenheit and can literally fry our brain.
How do we keep safe with sky-high temperatures?
—Limit strenuous activities to the morning and evening hours, when it
—Pretend we are fish. Not only does drinking fluids cool us down, it
is necessary to replace what is lost from sweating and perspiration.
The key is to drink consistently throughout the day, not just when we
feel thirsty. If we are engaging in strenuous activities, set a goal
to drink 2-4 eight-ounce glasses of fluid EVERY hour. Additionally, we
need to be aware that alcoholic, caffeinated, and sugary drinks
increase urination and, hence, cause fluid loss.
—Dress for success. Lightweight clothing allows our body to dissipate
heat instead of insulating it. Light-colored clothing reflects heat
whereas darker colors absorb it.
—Don’t get burnt. In addition to increasing our risk for skin cancer,
sunburn prevents heat dissipation. The red that we see is actually
superficial broken blood vessels that will decrease blood flow to the
—Retreat to air-conditioned areas whenever possible.
—Hot Cars: Never leave a child in a car unattended, even for a moment.
Temperatures inside a car can increase, putting anyone in danger —
especially children. Heatstroke is the leading cause of non-crash,
vehicle-related deaths for children. When buckling our children in,
make sure that the belt buckles are not too hot, especially when the
car has been parked in the heat.
In July of 1776, there were an estimated 2.5 million people in our
newly found nation. Today, we have an estimated population of 316
million. It would be accurate to state that we have come a long way.
Let’s stay cool and safe as we celebrate our “Life, Liberty and
pursuit of Happiness.”
By Dr Nina Radcliff