Sunscreen Verses Sunblock

Comic from 2003

Did you know that eighty percent of skin damage by the sun is done before you reach the age of eighteen? Although ultra-violet radiation is essential to our health and wellbeing, long days in the sun damage our cells and put us at higher risk for skin cancer. Protecting our skin can be done by using topical concoctions known as sunscreens and sunblocks. But what's the difference? Which is better?

The major difference between sunscreen and sunblock is how they react with the UV rays and which rays they protect against. Sunscreen is what is known as a chemical blocker. It absorbs the UVB rays and scatters them, causing the length of the waves to alter just enough to limit the damaging affect of overexposure. Sunblock; however, is what is known as a physical blocker. Sunblocks actually reflect both visible and UV light. Sunblocks are a great source of long term coverage for both UVA and UVB rays with up to ninety-nine percent effectiveness.

The most common chemicals found in sunscreens are para-aminobenzoic acid (PABA), benzophenones, cinnamates, and salicylates. The chemicals act as dyes and absorb UVB radiation. Although it is important to protect ourselves from the sun, applying these chemicals to our skin can be difficult due to allergies, staining, odor, and their greasy nature. Before slathering yourself with a new sunscreen, it might be wise to test a small amount on your arm or leg.

Sunblocks most commonly are made from zinc oxide or titanium dioxide. In the past they are usually opaque creams but in today’s market are now refined to be more acceptable in modern day society.

So which is better? Both do the job; however, even with the refinement of sunblocks the manufacturers lean toward the production of sunscreens which we find in our stores today. But no matter if you choose a sunscreen or a sunblock it is very important to choose the right one for you. Think of your skin type and the amount of sun protection (SPF) you will need for the time you overexpose you in the sun.


Sunscreen Chemistry
Vitamin D Synthesis
Discovery of Sunscreen Active Ingredients
Skin Cancer
Portrait of the Sun SPF
Want to Know More?
Ultra-Violet Radiation
Lesson Plans