Don’t you just hate it when your swim goggles fog up? I remember when I was a kid, I heard so many theories about how you can prevent this; from wetting the goggles in cold water, spitting on them, or just leaving them completely dry. We were too cheap to have any anti-fog spray on hand, so these were the options we resorted to back then.
If you have an anti-fog product with you, then follow the instructions for that. Typically, that means coating the lenses evenly with the anti-fog solution when it’s dry and then rinsing off any excess solution before wearing it.
Those of you who aren’t using an anti-fog spray should spit on your goggles’ lenses (or give it a good licking to be more thorough) and then rinse off the excess spit with water before swimming. Saliva is a natural anti-fog, easily accessible, and best of all, it’s free.
You should wet your goggles before swimming, but not right away. The confusing part for a lot of people is that when you are applying the saliva or anti-fog, the goggles need to be completely dry at first. If it is already wet during application, it will reduce the effectiveness of your saliva or anti-fog solution. Only after application can you briefly rinse the excess saliva or anti-fog off and then you can start swimming.
Keep reading on to learn about how saliva works as a natural anti-fog, the ways you can keep your mask from fogging up, and what you shouldn’t do that will cause your mask to fog up faster.
Before you swim
There are two main methods you can prepare your goggles with before swimming so that it takes much longer to fog up, if at all. Spitting on your goggles is free and always an option, but it can feel kind of unhygienic. Anti-fog is cheap and effective, but perhaps you’d rather not spend money in the first place when a free and effective but somewhat icky option is available.
Regardless of which option you choose, both of them start from when you are dry and your goggles are dry. If your goggles are already wet, dry it again for these methods to be at their most effective.
Spitting on the lenses
Spit on the inside of the lenses until it is completely coated with your saliva. You can also swish the saliva around the lenses to help it spread more evenly. Another method is to directly lick the inside of the lenses (make sure it’s clean and dry first). Do NOT use your fingers to spread the saliva.
Once the lenses have been thoroughly coated, rinse off the excess saliva by briefly dipping it underwater and giving it a good shake. Now it should be ready to wear for swimming.
The order of the steps is important, don’t reverse or combine steps. Do not grab a mouthful of water and spit the mouth water mixed with your saliva on the lenses. Some people prefer this method because it feels less icky, but it’s less effective. Coat the dry lenses with your saliva first, then rinse it with water afterwards.
Applying anti-fog on the lenses
Coat the inside of the lenses with anti-fog. Make sure you don’t touch the lenses directly with your fingers as you try to coat the lenses. Anti-fog products can come in spray form so that it’s easier to accomplish this without touching the lenses with your fingers. You can also just buy a small spray bottle yourself and transfer your anti-fog to this spray bottle.
After you have successfully coated the inside of the lenses with anti-fog, quickly rinse off any excess by briefly rinsing the goggles with water.
After swimming for some time, your anti-fog can get fully saturated and your goggles will start fogging up again. Just rinse it with water to clear it. At this point, you can decide if you want to reapply more anti-fog, in which case you have to get out of the pool, dry the goggles, and apply anti-fog again. Or you can just spit on your goggles, using your saliva as a natural anti-fog, and continue swimming.
How does saliva prevent goggles from fogging up?
Anti-fog is a surface active agent, or surfactant, and saliva is one too. Surfactants are wetting agents that decrease the surface tension of a liquid, allowing it to spread more easily.
What does that mean exactly? Have you ever noticed how small beads of water tend to combine together to form larger droplets? Surfactants prevent that by breaking the water up into smaller droplets and helping it spread more easily.
When your mask fogs up, essentially what is happening is water from condensation mounds up as beads or droplets, completely covering your field of vision. With a surfactant applied, the droplets do not form up along the lenses and just slide down into the bottom of the goggles, keeping it clear.
Saliva is actually a fantastic surfactant. Other than the fact that it’s free and readily available, it also doesn’t irritate your eyes unlike how a detergent, soapy liquid, or other anti-fog product might. That said, you can get anti-fog made of purely natural ingredients to prevent this, and spit is also all natural.
You can run out of anti-fog or forget to bring it with you, but you will always be able to rely on your saliva as a natural anti-fog.
Avoid touching the lenses with your fingers
It’d be so much easier to apply your saliva or anti-fog to the lenses if you could just spread them with your fingers, but that can cause your mask to fog up faster.
Generally, swim goggles will come with a protective anti-fog film already on the inside of the lenses, so you shouldn’t need to use spit or anti-fog at first. However, if you rub the inside of the lenses with your finger, you will break down and remove this anti-fog film faster.
Furthermore, your fingers are oily and you will smear your oil onto the lenses. The oil is something that dirt specks can attach onto, and moisture can attach onto the dirt specks. A dirty pair of goggles is more likely to fog up, so try your best to keep it clean.
With a clean pair of goggles and a surfactant applied to its lenses, the moisture cannot form droplets and will simply sheet down and collect at the bottom instead of fogging up.
To clean your goggles, you can use toothpaste and a toothbrush to scrub the lenses with. Afterwards, rinse it thoroughly with freshwater and leave it out to fully air dry. You don’t have to do this after every swimming session, but it’s recommended you do this from time to time or when you notice the goggles are dirty.
The bottom line
In this article, we covered why you should wet your goggles before swimming. It is important to note that you should only wet your goggles as a second step after applying a surfactant to keep it from fogging up.
Wetting your goggles first and then applying the surfactant second will cause the surfactant to coat the surface of the lenses unevenly, reducing its effectiveness. If it is already wet, first dry your goggles, then apply anti-fog or saliva, then rinse off the excess.
When rinsing off the excess anti-fog or saliva, do it just once and very briefly. Rinsing too much will wash the surfactant off. Also avoid touching the lenses with your fingers, because you can smear off your anti-fogging product and introduce oils to the lenses, increasing the likelihood of the goggles fogging up.