
Spray on sunscreens are not as effective.
A spray on sunscreen may be convenient and less work, but they are not as effective as products you have to rub into your skin. This is partly because FDA regulations do not apply to spray on products, and thus do not require the same standards and testing as rub on sunscreens. So if you happen to be using a spray on sunscreen, be sure to use an ample amount and to rub it thoroughly into your skin.
You need as much sunscreen as a shot glass full.
To really protect your skin, you should use the shot glass size rule. This means that for one full application, you should be using about the same amount of sunscreen that would fit inside a full shot glass. This is a good way to remember just how much sunscreen to use, and that you need to use this amount for every single application.
There are two types of sunscreen.
Chemical and physical are the two types of sunscreen, which have different ingredients and uses. Chemical sunscreen contains ingredients like avobenzone, oxybenzone, and octinoxate. This type works like a sponge and absorbs the sun’s rays, and it is easier to apply. Physical sunscreen contains ingredients like zinc oxide and titanium dioxide – it is a true shield, reflecting UV rays and is great for more sensitive skin.