礦物防曬乳與化學防曬乳：您應該使用哪一種？

Recently, more people have started to choose mineral sunscreens over chemical ones, mainly because they are concerned about possible health risks, environmental pollution, and how well these products protect the skin. But is there a real difference between mineral and chemical sunscreens, or is it just a matter of preference and misunderstanding? Mineral sunscreens are becoming more popular as people worry about the effects of chemical sunscreens on our bodies, our brains, and even on coral reefs. However, many of the things people believe about these two types of sunscreens are not completely true. For example, some people think mineral sunscreens do not contain any chemicals, or that chemical sunscreens have been proven to be dangerous, or that chemical sunscreens only absorb the sun’s rays while mineral ones only reflect them. These ideas are not accurate.

The confusion starts with the words we use. Everything around us is made of chemicals, including water and air. What people call chemical sunscreens are actually called organic because they contain carbon and hydrogen. Mineral sunscreens, also called inorganic, are made from things like titanium dioxide and zinc oxide, which do not have those bonds. Both types are still chemicals. Modern sunscreens, made from a mix of different ingredients, are much better at protecting our skin from the sun than the old sunscreens from a hundred years ago.

Trying to protect our skin from the sun is not new. People have used hats, clothes, and even special pastes for thousands of years. In Africa, some groups have used natural pastes as sunscreen for a very long time. In ancient Rome, people used olive oil. Scientists started to understand the sun’s rays in the 1800s and found that some things, like quinine from tree bark, could help block the sun. By the 1930s, more ingredients were found that could protect the skin, but they were not as strong as today’s sunscreens. Later, scientists made even better sunscreens in the lab, called synthetic chemicals, which absorb the sun’s rays much better.

Mineral sunscreens also became available, but even though they seem more natural, the titanium dioxide and zinc oxide in them are usually made in labs. At first, people thought chemical sunscreens absorbed the sun’s rays and mineral ones reflected them, like an umbrella. This idea was even written in a government report in the 1970s. But this is not really true. Both types mostly absorb the sun’s rays. Only a small part is scattered, not really reflected. Some sunscreens even use both types of ingredients.

The way the sunscreen feels on your skin is different because of how the ingredients mix. Most chemical sunscreens are soluble, which means they can be mixed into water or oil and feel smooth and clear on the skin. Mineral sunscreens are not soluble, so their particles stay whole and can feel thicker and look white on the skin. But now, scientists have made the mineral particles smaller, so they do not look as white. Some people worry that these tiny particles could get into the skin, but studies show they mostly stay on the top layer.

Both types of sunscreens mostly work at the surface of your skin. Some chemical sunscreen ingredients can get into your blood, but there is no good proof that this is harmful. Most studies that found problems used very large amounts on animals, much more than people would ever use. For example, in one study, baby rats were given huge amounts of a sunscreen ingredient, and it affected their bodies. But for a human to get the same amount, they would have to use sunscreen every day for hundreds of years.

Some people are also worried about sunscreens hurting coral reefs. Most studies were done in labs, not in the real ocean. Even in places with lots of sunscreen in the water, the amount is much lower than what caused problems in the lab. Still, some places like Hawaii have banned certain sunscreens just to be careful.

In the end, scientists say the best sunscreen is the one you will use. Both types protect your skin from the sun, which is important because too much sun can cause skin cancer. It does not really matter if the sunscreen is mineral or chemical, as long as it has a good SPF and you use it often. The most important thing is to protect your skin from the sun’s harmful rays.