New Delhi: Skin cancer is one of the most common types of cancer worldwide, with millions of cases diagnosed every year. Exposure to the sun’s ultraviolet (UV) rays is a major risk factor for skin cancer, and using sunscreen is a crucial step in preventing this disease. Dr Mangesh P Kamath, Additional Director, Medical Oncology, Fortis Hospital, Cunningham Road, Bangalore, explained how using sunscreen is a good way to reduce skin cancer risk effectively.

The Role of UV Rays in Skin Cancer

UV rays from the sun or tanning beds damage the DNA of skin cells, leading to mutations that can cause cancer. There are two types of UV rays: UVA and UVB. UVA rays penetrate deep into the skin, causing premature aging and increasing the risk of skin cancer. UVB rays, on the other hand, are primarily responsible for causing sunburn and also play a role in skin cancer development. The intensity of UV rays varies depending on the time of day, season, and location, but they are always present, even on cloudy days.

How Sunscreen Prevents Skin Cancer

Sunscreens work by absorbing or reflecting UV rays, preventing them from penetrating the skin. There are two types of sunscreens: physical sunscreens, which contain zinc oxide or titanium dioxide, and chemical sunscreens, which contain ingredients like oxybenzone or avobenzone. Physical sunscreens sit on the skin’s surface and reflect UV rays, while chemical sunscreens absorb UV rays and convert them into heat, which is released from the skin.

Studies have consistently shown that using sunscreen reduces the risk of skin cancer. A study published in the Journal of the American Academy of Dermatology found that regular sunscreen use reduced the risk of melanoma, the deadliest form of skin cancer, by 50%. Another study published in the Journal of Investigative Dermatology found that sunscreen use reduced the risk of squamous cell carcinoma, a common type of skin cancer, by 39%.

Choosing the Right Sunscreen

Not all sunscreens are created equal. When choosing a sunscreen, look for the following:

1. Broad-spectrum protection: Choose a sunscreen that protects against both UVA and UVB rays.
2. SPF: Opt for a sunscreen with an SPF of at least 30. However, higher SPF values do not offer greater protection, and the difference between SPF 50 and SPF 100 is negligible.
3. Water-resistance: If you plan to be in the water or sweat heavily, choose a water-resistant sunscreen.
4. Physical or chemical active ingredients: Both types of sunscreens are effective, but physical sunscreens may be more suitable for sensitive skin.

Applying Sunscreen Correctly

To get the most out of your sunscreen, apply it correctly:

1. Apply 15-30 minutes before going outside: Allow the sunscreen to absorb into the skin before exposure to the sun.
2. Use enough sunscreen: Apply one ounce (about a shot glass full) of sunscreen to cover all exposed skin.
3. Reapply every two hours: Reapply sunscreen every two hours or immediately after swimming or sweating.

Skin cancer is a preventable disease, and using sunscreen is a crucial step in reducing the risk of this disease. By choosing the right sunscreen and applying it correctly, you can enjoy the sun safely and reduce your risk of skin cancer. Remember to combine sunscreen use with other forms of sun protection, such as seeking shade, wearing protective clothing, and avoiding peak sun hours, to enjoy the sun safely.