I’ve heard many anecdotes over the years about how wet skin supposedly tans or burns faster. When I asked how this was the case, the answer I received was that the water droplets on the skin act as a magnifying lens, focusing and intensifying the sunlight onto your skin.
This seems plausible at first, but already I had questions. The amount of sunlight reaching the skin through the water droplet would be the same, or even less, because water can reflect UV rays away or absorb some of it itself.
Also, if the water droplets were focusing the sunlight on a specific point, then wouldn’t there be dark dots on the skin wherever there was a water droplet focusing the UV ray? You’d see people with polka dot tans, essentially, but I have never seen such a tan before.
Furthermore, there is the issue of the sunlight’s contact angle. For it to be focused on your skin, it would essentially have to be directly above you, shining down at a 90º angle, otherwise the sunlight is being redirected elsewhere.
All of these concerns lead me to believe that you do not tan faster when wet. Furthermore, there are many ways that being wet can indirectly cause you to get tanned and sunburned. For instance, it can cause your skin to feel nice and cool despite being blasted by harsh UV rays. Water can also rinse off sunscreen that was recently applied, removing the sun protection you thought you had. Lastly, the reflection of sunlight off the surface of the water can cause you to receive twice the UV radiation you normally would. These situations can cause you to think that being wet causes faster tanning.
Let’s go over these situations in greater detail below.
Does being wet help you tan faster?
I don’t think that being wet inherently makes you tan faster, but there are many reasons why it can certainly feel that way.
Being wet can make you think you’re not burning
Being wet may not necessarily cause you to tan faster, but since it has a cooling effect, it may deceive you into staying out in the sun for longer without realizing that you’re getting deeply tanned.
When you’re by the pool, beach, or lake, unless you’re strictly there to lounge, chances are that you will be in the water having some fun in the sun. Time sure goes by when you’re having fun, right? Many people will lose track of time and forget to reapply their sunscreen, allowing a window of time when they are directly exposed to the sun’s harsh UV rays.
Plus, since water has a cooling effect, you won’t feel like you’re getting burned. Your skin could already have sustained some UV damage, but since you feel nice and cool, you get a false sense of security that you haven’t turned into a dinner roast.
These factors combined will cause you to feel like time flew by and “suddenly” you are badly sunburned and tanned.
Water can reflect and amplify sunlight
The main reason why people think that water droplets on your body can cause you to tan faster is because water can reflect and amplify sunlight. While it is true that sunlight can get amplified, small water droplets all over your body are not likely to do very much.
However, when the water source is as large as the ocean, that is enough to cause a powerful amplifying effect. Think of the ocean as essentially a giant mirror. Mirrors can reflect and focus the sunlight into a very intense beam of light on a specific spot.
We see this phenomenon happen so often in adventure movies like Indiana Jones that it has become a recognized trope: the light and mirrors puzzle. It’s not just some movie magic, this is a real thing.
When this beam of light is directed on a person, it is like getting a super dose of UV radiation far above what you’d normally get when you’re just outdoors in the sun. Many fishermen, surfers, and people laying on the beach have gotten deeply tanned and sunburned from the sunlight reflecting off of the water’s surface.
Conversely, being underwater will limit how often these light reflections hit you as well as the intensity of the sun’s UV rays as it penetrates through, and thus swimmers and snorkelers are actually somewhat protected compared to the people above the water.
There is a connection that people have made with being wet and tanning faster, but I think what’s happening is that these people just happened to be wet while the ocean was reflecting a bunch of UV rays onto them.
Water can wash off sunscreen
I hope you read the label of your sunscreen and paid attention to the part that says you should apply the sunscreen at least 15-30 minutes before you head out. A common mistake people make is they apply sunscreen and immediately head into the water where it is promptly washed off.
Waiting 15-30 minutes gives the sunscreen time to get absorbed into your skin so that it will not be washed or rubbed off. The sunscreen you apply must also specifically be water-resistant so that it doesn’t get washed off by sweat, and can even be applied onto your skin when you’re already wet. Naturally, if your sun protection is washed off, then you will burn and tan much faster when wet.
Using the water reflection to your advantage
If you want your beach tanning to be twice as effective, we can take advantage of the knowledge that sunlight reflects off the surface of the water and amplifies the UV rays.
Sunlight reflects off the water’s surface the most when the sunlight’s angle is low, which typically occurs around sunrise and just before sunset. This allows you to receive a concentrated dose of UV rays which can give you a dark tan.
The risk here is that it is very difficult to control your UV exposure. With a double dose of UV radiation, you can easily tan too much, get sunburned, and increase your risk of developing skin cancer.
Be careful when tanning
At the end of the day, all tanning is technically skin damage caused by UV radiation. Tanning is not recommended by dermatologists because excessive exposure to sunlight without sun protection can result in photoaging (wrinkles), dry skin, sunburn, and skin cancer.
Rather than worrying about whether you can tan faster when wet versus dry, the safest way to get a tan is to use a sunless tanner. This gives you the dark tan you are looking for with none of the downsides of UV exposure.
If you still want to get a little bit of a natural tan, the second safest thing to do is to wear broad-spectrum, water-resistant sunscreen that is SPF 30 or higher. This still allows some UV rays to penetrate, but for the most part you are protected and can control your tan much more easily.
