Sunscreens and Sunblock

 In Cancer Prevention, Cosmetic Surgery, Cosmetics, Medical Treatments, Skin Cancer, Skin Conditions

Sun protection such as sunscreens and sunblocks should be applied daily, regardless of age, to prevent the short and long-term damaging effects of the sun, and recommended to be used in conjunction with other sun-safety methods.

UV radiation from the sun, tanning beds, or sunlamps may cause skin cancer and can have a damaging effect on the immune system.  It can also cause premature aging of the skin, causing wrinkles to form.  Wrinkles tend to form where your skin gets the most exposure to the sun.

The Cause of Sun Damage

The sun has two major types of ultraviolet radiation: Ultraviolet A (UVA) and Ultraviolet B (UVB).  UVA rays are present during all daylight hours and throughout the winter months.  Although UVA rays are less intense than UVB rays, they are recognized as a deeper penetrating radiation that causes more damage since it is present all year round. Year-round exposure from UVA rays causes more susceptibility  to skin disease.  UVB rays are responsible for burning, tanning, and the acceleration of skin aging.  This plays a very key role in the development of skin cancer.  The intensity of UVB varies by season, location and time of day.  The most significant amount of UVB hits between 10 AM and 4 PM during the months of April thru October.

Sunburn can be characterized by red, painful skin that feels hot to the touch.  It usually appears after a few hours of sun exposure and may take several days or longer to fade.  Sunburns can occur on both hot sunny days and cloudy days.  Any part of the body can burn, including the earlobes, scalp, lips, and eyes.

Overexposure to ultraviolet (UV) light causes sunburns.  UV radiation reaches the earth in invisible wavelengths.  Wavelengths can bounce off of reflective surfaces such as concrete, snow, ice, sand, and water, which can burn the skin as severely as direct sunlight.  The skin accelerates its production of melanin when exposed to UV light.  Melanin is the pigment that gives the skin its color.  The body defends itself from ultraviolet light by creating a suntan to prevent sunburn and other skin damage.  However, this protection is limited.  Genetics contribute to the amount of melanin a person produces.  Many people simply can’t produce enough melanin to effectively protect the skin.  It is then that UV light causes the skin to burn, bringing pain, redness, and swelling.

Sun Protection

In order to prevent skin damage and reduce the risk of cancer it is vital to use sun protection.  The first step to effective sun protection is to avoid peak sun hours.  Wear protective covering such as broad-brimmed hats, sunglasses, long pants, and long-sleeved shirts to reduce sun exposure.  Use a broad-spectrum sunscreen which will block both UVA and UVB with an SPF of at least 15 or higher on all exposed skin, even on cloudy days.  Apply the sunscreen 30 minutes prior to sun exposure and reapply every 1½ to 2 hours.

Sunscreens work by absorbing and reflecting the sun’s rays on the skin.  They are available in many forms, including ointments, creams, gels, lotions, sprays, and wax sticks.  All sunscreens are labeled with sun protection factor (SPF) numbers.  The higher the SPF is, the greater the protection from the sun.  Broad spectrum sunscreens are the most recommended because they block out both UVA and UVB rays.

It is important to take precautions when performing certain activities outdoors.  Make sure to take precautions when in places of higher elevations or on reflective surfaces such as concrete, sand, snow, or water.  These factors may increase the likelihood of sun damage to the skin.  Keep in mind activities that produce excess sweat, such as outdoor jobs, sports, exercise, prolonged sunbathing, or water sports, may remove the sunscreen agent from the skin.  Sunscreens should be applied 30 minutes prior to any sun exposure.  These products should be applied every 1 to 2 hours for adequate protection.  Although certain items may provide shade, such as beach umbrellas, UV rays can still bounce off of reflective surfaces.  Thus, sunscreens should be worn all the time.

Sunscreens – How They Work

Sunscreens combine organic and inorganic chemicals to filter, reflect, or scatter the sun’s rays so that it doesn’t reach the outer or deeper layers of the skin.  All sunscreens are labeled with Sun Protection Factors (SPF) numbers.  This number can help determine how long the skin can be exposed to the sun before getting a sunburn.  Broad-spectrum sunscreens protect against both UVA and UVB rays.

Types of Sunscreens

Sunscreens come in many different forms, including spray, lotion, cream, powder, or wax sticks.  The form of sunscreen that is chosen depends on a patient’s personal preference and which area of the body is being covered.  Creams are ideal for dry skin and to be applied on the face.  A gel or spray might work better for areas covered with hair, such as the scalp.

For optimal sun protection, use water-resistant, broad-spectrum coverage sunscreen that has an SPF of at least 15 or higher.  Check the expiration date, and follow the directions on the label.  It is important to keep in mind that:

  • Only sunscreens that offer protection from both UVA and UVB rays can advertise broad-spectrum coverage on the label.
  • Only broad-spectrum sunscreens with an SPF of 15 or higher can claim to reduce the risk of skin cancer or prevent early skin aging.
  • Any claims about reducing the risk of skin cancer or early skin aging must be accompanied by other sun-safe measures, such as wearing protective clothing and avoiding midday sun.
  • Sunscreens can’t be advertised as sweatproof or waterproof.
  • Sunscreens that pass a water resistance test can be labeled “water resistant” for either 40 or 80 minutes, as long as they also include instructions to reapply after 40 or 80 minutes of swimming or sweating, immediately after towel drying, and at least every two hours.

Proper Use of Sunscreen

Sunscreen should be applied generously and evenly to the skin 30 minutes prior to going outdoors.  It should be applied on all skin surfaces that will be exposed to sun, especially the face, ears, hands, arms, and lips.  Reapply sunscreen every one to two hours, especially after swimming, drying off, or perspiring.  Remember that sand, water, and snow reflect sunlight, thus it is vital to apply sunscreen when performing activities on these surfaces.   Since UVA rays penetrate glass and clouds, it is important to use sunscreen when it’s cloudy or in a room with lots of windows.  Sunscreen can be applied to children as young as 6 months old.  Keep younger children in the shade as much as possible.  The earlier these steps are taken, the better.

Tips for Sun Protection

  1. Stay out of the sun when it is strongest, between 10 a.m. and 4 p.m.
  2. Use a broad-spectrum sunscreen which will block both UVA and UVB with an SPF of at least 15 or higher on all exposed skin, including the lips, even on cloudy days.
    1. Apply the sunscreen 30 minutes prior to sun exposure and reapply every 1½ to 2 hours.
    2. Wear protective covering such as broad-brimmed hats, long pants, and long-sleeved shirts to reduce sun exposure.
    3. Seek shade whenever possible.

Check the skin regularly for changes in the size, shape, color, or feel of birthmarks, moles, and spots, such changes may be a sign of skin cancer.  See a dermatologist if you notice an unusual mole, a scaly patch, or a sore that does not heal.


A safe alternative to tanning is the use of self-tanners which give the skin a tanned look without exposing it to harmful ultraviolet rays.  Sunless tanning products are commonly sold as creams, gels, lotions, and sprays that are applied to the skin.  These products contain an active ingredient called dihydroxyacetone.  When applied to the skin, this ingredient reacts with dead cells in the outermost layer of skin to temporarily darken the skin’s appearance.  This coloring typically lasts a few days and does not wash off.  However, most sunless tanning products do not contain sunscreen.  Therefore, sunscreen with an SPF of at least 15 or higher should be used and reapplied every one to two hours in combination with the sunless tanning products.

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