MedicineNet.com

About Us | Privacy Policy | Site Map
February 8, 2012

Sun Protection and Sunscreens

Medical Author:
Medical Editor:
Making Sense of Sunscreen Products

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: Barbara K. Hecht, PhD

Find out how to choose the best sunscreen.Most people are understandably confused when it comes to choosing a sunscreen because of the baffling array of available choices. Common questions about sunscreens include

  • How high should the SPF be?
  • Should it block UVA or UVB?
  • Does it matter whether it is a gel, cream, or spray?
  • Should it be water-resistant or waterproof?

SPF stands for sun protection factor. The SPF numbers on a product can range from as low as 2 to as high as 60. These numbers refer to the product's ability to screen or block out the sun's burning rays. The SPF rating is calculated by comparing the amount of time needed to produce sunburn on protected skin to the amount of time needed to cause a sunburn on unprotected skin. The higher the SPF, the greater the sun protection. However, it is a common mistake to assume that the duration of effectiveness of a sunscreen can be calculated simply by multiplying the SPF by the length of time it takes for him or her to suffer a burn without sunscreen, because the amount of sun exposure a person receives is dependent upon more than just the length of time spent in the sun. The amount of sun exposure depends upon a number of factors including the length of exposure, time of day, geographic location, and weather conditions.

What is sun protection?

Sun protection is simply guarding a body from the adverse effects of sunlight. Aside from the hazards of heat, the sun poses the danger of sunburn, which can permanently damage the skin and cause skin cancer, precancerous changes in the skin, as well as premature wrinkling and signs of aging. Exposure to ultraviolet rays from the sun is a known risk factor for the development of both melanoma and non-melanoma skin cancers.

How is sunburn best prevented?

The best ways to avoid sunburn are to

  • limit time in the sun, especially between peak sunlight hours of 10 a.m. and 3 p.m.;


  • wear protective clothing, including


    • a broad-brimmed hat,


    • a shirt with sleeves that cover the arms, and


    • a long skirt or pants with long legs; and


  • use a protective sunscreen to minimize the penetration of the sun's ultraviolet (UV) rays.

What is sunscreen?

Sunscreen is any substance or material that protects the skin from UV radiation. Sunscreens are available in the forms of topical lotion, cream, ointment, gel, or spray that can be applied to the skin; a salve or stick that can be applied to the lips, nose, and eyelids; a moistener in towelettes that can be rubbed against the skin; sunglasses that protect the eyes; certain types of sun-protection clothing; and film screen that can be affixed to the windows of a car, room, or office.

What is meant by SPF?

SPF, an abbreviation for sun-protection factor, is a number such as 15, 30, or 50 that indicates the degree of sunburn protection provided by sunscreens. SPF is related to the total amount of sun exposure rather than simply the length of sun exposure. It is a common mistake to assume that the duration of effectiveness of a sunscreen can be calculated simply by multiplying the SPF by the length of time it takes for him or her to suffer a burn without sunscreen, because the amount of sun exposure a person receives is dependent upon more than just the length of time spent in the sun. The amount of sun exposure depends upon a number of factors including the length of exposure, time of day, geographic location, and weather conditions.

A common mistake is applying too little sunscreen, which can drastically reduce the effective SPF of the product. About 1 ounce (5-6 teaspoons) of sunscreen is recommended to cover the entire body. Further, sunscreen must be reapplied every two hours when staying outdoors for a prolonged period of time. Sunscreen should also be applied at least 30 minutes before going outdoors.

People with sensitive skin who burn quickly and must spend a lot of time outdoors should always apply a sunscreen with an SPF of 30 or more.




MedicineNet Doctors

Suggested Reading on Sunscreen by Our Doctors

  • Related Diseases & Conditions

    • Eczema
      • Eczema, also known as dermatitis, is a general term for many types of skin inflammation. The most common form of eczema is atopic dermatitis. The other forms of eczema include: contact eczema, seborrheic eczema, Nummular eczema, Neurodermatitis, stasis dermatitis, and dyshidrotic eczema. Symptoms, diagnosis, and treatment of eczema may vary from person to person and may depend on the type of eczema.
    • Skin Cancer
      • Skin cancer is the most common form of cancer in humans. There are three main types of skin cancer; basal cell carcinoma and squamous cell carcinoma (the nonmelanoma skin cancers), and melanoma.
    • Heat Rash
      • Heat rash is a skin irritation caused by excessive sweating. It can occur at any age and it appears as a rash that itches or feels prickly, and looks like a red cluster of pimples or small blisters. Pictures of heat rash are included.
    • Melanoma
      • Melanoma is a type of skin cancer which begins in skin cells called melanocytes and affects more than 53,600 people in the United States each year. These melanocytes can grow together to form benign moles which, after a change in size, shape, or color can be a sign of melanoma. Caused by sun exposure, early detection becomes extremely important to avoid a spread to other areas of the body. Diagnosis is confirmed through a biopsy of the abnormal skin and treatment depends on the extent and characteristics of the patient.
    • Burns (First Aid)
      • Burns are categorized by severity as first, second, or third degree. First degree burns are similar to a painful sunburn. The damage is more severe with second degree burns, leading to blistering and more intense pain. The skin turns white and loses sensation with third degree burns. Burn treatment depends upon the location, total burn area, and intensity of the burn.
    • Vitamins and Calcium Supplements
      • Vitamins are organic substances that are essential for the proper growth and functioning of the body. Calcium is a mineral essential for healthy bones and is also important for muscle contraction, heart action, and normal blood clotting.
    • Freckles
      • Freckles are flat circular spots on the skin that may be red, yellow, tan, light brown, brown, or black in color. Lentigo is the term used to describe certain types of darker freckles. Ephelis typically appear during the sunny months. Freckles can be prevented with sunscreens, the use of wide-brimmed hats, sun-protective clothing, avoiding peak sun hours, and seeking shade and staying indoors.
    • Melasma
      • Melasma is a patchy brown discoloration of the skin on the face. When it occurs in pregnancy, it's called chloasma. Melasma is commonly treated with hydroquinone creams.
    • Moles
      • Moles are small skin growths that may appear flat or raised and are often tan, brown, black, reddish brown, or skin colored. They are typically about the size of a pencil eraser. There are three types of moles. Monthly skin self-exams are essential in the early detection of abnormal moles and melanomas.
    • Sun-Sensitive Drugs (Photosensitivity to Drugs)
      • Sun sensitivity (photosensitivity) is an inflammation of the skin induced by the combination of medications or substances and sunlight. The affect on the skin is redness, which looks similar to a sunburn. Generally, these reactions are either phototoxic or photoallergic. Phototoxic drugs are more common than photoallergic drugs. Symptoms of phototoxic reactions are a burning and stinging sensation and then redness. Symptoms of photoallergic reactions are itching, redness, swelling, blisters of the affected area. Treatment generally is discontinuation of the medication and topical application of creams.
    • Sunburn (Sun Poisoning)
      • Sunburn is caused by overexposure to UV radiation from the sun. UV rays can also damage the eyes. Repeated overexposure to UV rays also increases the risk for scarring, freckles, wrinkles, and dry skin. Symptoms of sunburn include painful, red, tender, and hot skin. The skin may blister, swell, and peel. Sun poisoning (severe sunburn) include nausea, fever, chills, rapid pulse, dizziness and more. Treatment for sunburn depends upon the severity. Sun protection and sunscreen for an individual's skin type is recommended to decrease the chance of sunburn.
    • Vitamin D Deficiency
      • Vitamin D deficiency has been linked with rickets, cancer, cardiovascular disease, severe asthma in children and cognitive impairment in older adults. Causes include not ingesting enough of the vitamin over time, having limited exposure to sunlight, having dark skin, and obesity. Symptoms include bone pain and muscle weakness. Treatment for vitamin D deficiency involves obtaining more vitamin D through supplements, diet, or exposure to sunlight.
    • Wrinkles
      • Wrinkles, whether they be fine line or deep furrows, typically appear on areas of the body that receive a high amount of exposure to the sun. Smoking, light skin type, hairstyle, the way you dress, your occupational and recreational habits, and heredity are all factors that promote wrinkling. Medical treatments for wrinkles include antioxidants, moisturizers, alpha-hydroxy acids, and vitamin A acid. Cosmetic procedures that treat wrinkles include dermabrasion, microdermabrasion, glycolic acid peels, laser resurfacing, Botox, and fillers.
  • Medications

  • Procedures & Tests

  • Pictures, Images & Illustrations

  • Doctor's & Expert's Views

  • Health News

  • Health Features

Women's Health

Find out what women really need.



Symptom Checker: Your Guide to Symptoms & Signs: Pinpoint Your Pain



Sunscreen

Introduction

Although wrinkles can signify wisdom, most people nowadays would rather not have them.

Many products and procedures promise to reduce wrinkles. Some do little or nothing (like the products that claim they reduce "the appearance of fine lines," which means that they don't reduce the lines themselves). Others can achieve a fair amount of success.

Skin ages all over the body, but much more so where there has been sun exposure. Changes brought on by sun damage (photoaging) include "dryness" (really roughness), sagginess, skin growths like keratoses ("liver spots"), and wrinkles.

Most wrinkles appear on the parts of the body where sun exposure is greatest. These especially include the face, neck, the backs of the hands, and the tops of the forearms. Wrinkles come in two categories: fine surface lines and deep furrows. Wrinkle treatments are in general much more effective for fine lines. Deeper creases may require more ...

Read the Wrinkles article »






Sun Protection and Sunscreens Related Supplements


Use Pill Finder Find it Now

Pill Identifier on RxList

  • quick,
    easy,
    pill identification

Find a Local Pharmacy

  • including
    24 hour
    pharmacies