Sun, Sun Exposure, Sun Screens, and Vitamin D

As a functional medicine doctor, I’ve seen firsthand the devastating impact of skin cancer on individuals and their families. The debate surrounding the effectiveness of sunscreen in preventing skin cancer and concerns about the safety of certain sunscreen ingredients is a complex one. In this article, I’ll explore the scientific facts surrounding sunscreen and skin cancer, and offer my perspective on this hotly debated topic.

The Science of Sunscreen

Sunscreen is a topical product designed to protect the skin from the harmful effects of ultraviolet (UV) radiation. There are two types of UV radiation: UVA and UVB.

1. UVA:
   • UVA radiation penetrates deep into the skin and is responsible for skin aging, wrinkles, and age spots.
   • UVA rays can also contribute to skin cancer development.
2. UVB:
   • UVB radiation affects the top layer of the skin and is responsible for sunburn.
   • UVB rays are also a major cause of skin cancer.

Sunscreen works by absorbing, reflecting, or scattering UV radiation, preventing it from reaching and damaging the skin. There are two main types of sunscreen: chemical and physical.

1. Chemical Sunscreens:
   • Chemical sunscreens contain compounds that absorb UV radiation and convert it into heat, which is then released from the skin.
   • Common chemical sunscreen ingredients include oxybenzone, avobenzone, and octinoxate.
2. Physical Sunscreens:
   • Physical sunscreens contain minerals like zinc oxide or titanium dioxide that reflect and scatter UV radiation.
   • Physical sunscreens are often preferred by individuals with sensitive skin or those looking for a more natural option.

The Effectiveness of Sunscreen in Preventing Skin Cancer

Research has shown that sunscreen can be effective in preventing skin cancer, particularly when used correctly.

1. Reduced Risk of Skin Cancer:
   • A 2011 study found that regular sunscreen use reduced the risk of squamous cell carcinoma by 40% and the risk of melanoma by 50% (1).
   • The American Academy of Dermatology recommends using a broad-spectrum sunscreen with an SPF of 30 or higher to reduce the risk of skin cancer.
2. Protection Against UV Damage:
   1. Sunscreen can protect against UV damage, which is a major risk factor for skin cancer (2).
   2. By preventing UV damage, sunscreen can help reduce the risk of skin cancer and other skin conditions, such as wrinkles and age spots.

Concerns About Sunscreen Safety

Despite the effectiveness of sunscreen in preventing skin cancer, there are concerns about the safety of certain sunscreen ingredients.