Our skin is made of three main layers. The epidermis, the outer layer, is the awaterproof semi-permeable barrier that provides our primary protection.  It is the main layer of protection that keeps out environmental invaders and keeps in essential body fluids.  The next layer is the dermis, which contains essential components such as collagen, elastin and hyaluronic acid to keep our skin plump, flexible and hydrated. The capillaries which deliver oxygen to our skin, the lymphatic pathways which help purify our skin and many sweat and oil glands also reside in the dermal layer. The third layer of the skin is the subcutaneous layer which provides a layer of fat to insulate out vital organs.

There are two types of ultra-violet rays emitted by the sun that are of concern.  UVB rays are known as “burning rays” that cause most of the immediate visible damage of sun exposure. Two types of skin cancer are caused by UVB rays: basal cell and squamous cell cancers. UVA rays are known as “aging rays” because they penetrate much deeper into the skin and cause damage that shows up 10 to 20 years in the future. Aging rays cause deep lines, tissue loss and dark pigmentation spots later in life by cross-linking collagen and elastin, degrading the natural moisturizers in the skin, damaging DNA, over-activating melanin and destroying immune cells. Two-thirds of all malignant melanomas are caused by UVA rays which are present from dawn to dusk even when it is overcast.

What Does SPF Measure?

SPF - Sun Protection Factor -  indicates the time it takes skin to form minimal redness.  SPF 30 means one thing for a person who burns in 5 minutes, and it means something different for someone who burns in 15 minutes.  If it normally takes a person 10 minutes to burn without protection then SPF 30 will protect for 10 X 30 or 300 minutes.  That is the total amount of time that person can be in the sun that day.  Reapplying SPF 30 will not give that person another 300 minutes.  It is recommended that you reapply every 1- 2 hours of constant exposure, especially is if something has caused the sunscreen to dissolve such as water or sweat.

Since SPF only measures minimal redness, it only refers to UVB rays which are the burning rays.  UVA sun damage occurs in the dermal layer; it is cumulative over a lifetime and its damaging effects are not immediate.  To protect yourself from UVA rays choose sunscreens with Zinc Oxide -  a physical sunscreen that reflect the sun’s rays off the surface of the skin.

 Do You Use Enough  Sunscreen Every Day?

To protect your face daily, I like to follow the “two finger rule.”  Run a line of sunscreen down the entire length of  your index finger and your middle finger. This is equal to ½ teaspoon and is enough sunscreen to cover your face and neck for the day if you are not planning on being out in the sun for any extended period of time.  If you are out for more than an hour of constant exposure - even if it’s cloudy - re-apply the same amount of sunscreen.

When you are at the beach or by the pool, kayaking, hiking or mountian biking how much sunscreen should you put on the rest of your body?  Sunscreen manufacturers are working within FDA guidelines which state that 1 ounce of sunscreen should be applied from the neck down for adequate protection.  That's one shot glass full of sunscreen.  Take a look at your sunscreen bottle.  If you are spending a week at the beach, you will need at least two 8 ounce bottles per person per week to allow for re-application after water sports.

1.  Choose a sunscreen that contains zinc oxide for UVA protection.  Not only is zinc oxide incredibly soothing to the skin, it also provides a physical reflector to the sun, meaning that the sun's rays hit the zinc oxide and bounce off.  Titanium Oxide is also a physical sunscreen and it is in many products.  I hesitate to recommend Titanium Oxide because when it is washed off at the end of the day, the tiny particles are getting into our water supply and are showing up in human and animal tissue. So, go with Titanium Oxide if you must, but always choose zinc oxide first.

2. Also choose a sunscreen that has one or two chemical sunscreens combined with the Zinc Oxide. The chemical sunscreens provide that UVB protection that is so essential.  Remember, chemical sunscreens need to be applied 20 minutes BEFORE going out.

3. Re-apply every 1-2 hours if you are out in the sun.  Office workers can get away with applying once a day in the morning.  But if you decide to eat lunch outside, try to avoid getting sun on your face and reapply sun screen to your arms.

4.  Children under 6 months should never be in direct sunlight for more than 5 minutes or so.

5. Be especially vigilant with children 6 months to 2 years old.  Use products formulated for babies preferrably with no chemical sunscreens:  zinc oxide only, and reapply after playing in the water. These products go on white and then fade into the skin.  You can see where you have put the sunscreen on the kids which is great for complete coverage.

6. If your skin turns pink, get out of the sun!  Applying sunscreen on red skin will not protect you! The damage is done. Now your skin needs to repair.

Please Note:

All information provided in this publication is for educational purposes only and not diagnostically prescriptive in nature.  The information offered is not a substitute for medical advice.