How much sunscreen do you really need to get protected?

I recently went to this magnificent island called Isla de Gigantes in Carles, Iloilo. Getting there is no walk in the park, as we had to take a four-hour roadtrip from Iloilo City to the municipality of Estancia, followed by a two-hour boat ride to get to the island. The troubles of getting there were worth it though, because Isla de Gigantes was breathtaking! 

Four hours later, while playing under the sun, I got myself a tan. I rarely leave the house, so in retrospect, getting a tan in four hours is probably normal… but I applied sunscreen before snorkeling! Aren’t I supposed to be protected since I applied sunscreen? The experience got me so confused that I decided to brush up on my knowledge about sunscreen. 

Here’s what I’ve learned!

Don't be stingy with sunscreen

The biggest mistake most people do, myself included, is not applying enough. Quite frankly, I understand why. Applying sunscreen is so messy — they’re sticky and often leave a nasty white cast. But if you really want to be well protected and achieve the same protection marked on the sunscreen’s label, make sure you apply generously on ALL areas of your body. Use about a teaspoonful for your neck and face, and a shot glass's worth PER LIMB.

If (understandably) you're not carrying a teaspoon or shot glass around with you, you can eyeball it by squeezing out a line of product from the tip of your middle finger down to the bottom of your palm. This amount is enough per limb.

You have to reapply it every two hours, or every chance you get

Another reason to love/hate sunscreen is the need to reapply. On a regular day, you should do it every two to three hours. If you’re swimming or spending way too much time outside, reapply every hour to get continuous protection.

You still need protection, even if your goal is to get a tan

I found out that whenever your skin gets exposed to UV light, you start to get a tan. Your natural tan is your body’s way of protecting its skin from burning. The only way to avoid a tan is to not expose yourself to anything that emits UV light, but that’s impossible in today’s tech-driven age (our computers emit UV rays, too!). 

Applying sunscreen basically prevents our skin from getting destroyed by the harmful effects of UV rays. You can still get darker, and though it'll take longer, it will also be less damaging to your skin. 

How much sunscreen do we really need to be protected? 

You’ve probably seen sunscreen lotions marked with an SPF of 15, 30, 50, 75, and even 100 label. Does this automatically mean the SPF 100 is better than the sunscreen with SPF 30? The answer is no. At SPF15, about 93% of UVB rays are blocked. SPF30 only increases the protection to 97% and SPF45 to 98%. There is no such thing as a sunscreen that offers 100% protection!

Some say that the SPF number is an indicator of how long your sunscreen will protect you, but that’s not true at all. You'll still need to reapply every few hours. The value of using a high SPF sunscreen, though, lies in being able to give you protection even if you don't apply the recommended amount of product. You can only get the protection promised on the label if you apply sunscreen correctly.

If you’re staying indoors 24/7, a sunscreen with SPF15 should suffice but most dermatologists still recommend using at least SPF30.

Have you been using sunscreen correctly? What SPF do you usually go for?