I do use a lip scrub, but I don't do so with a whole lot of reliability. I was curious, then, if a lip scrub made as big of a difference as makeup lovers suggest. Should I really make an effort to use one every day? I decided to put it to the test.
Personally, I like the Lush lip scrubs because they are edible, which appeals to both the part of me that is lazy (and thus doesn't want to get tools to wipe the scrub off) and the part of me that is hungry. With that said, you could presumably use any lip scrub on the market or you could make a homemade lip scrub out of brown sugar and olive oil and still get comparable longevity results, even if it doesn't happen to taste like bubblegum. For the test, though, Lush's Bubblegum Lip Scrub was my tool of choice.
(For me, Lush is convenient enough to be worth the $9.95 for 0.8oz, or $12.44 per ounce! It's also worth noting that a lot of more inexpensive options are pricier, ounce per ounce. For example, at $3 for 0.16oz, ELF's Lip Exfoliator is actually more expensive at $18.75 per ounce. Plain old sugar, though, will always be cheaper.)
I debated the best method to test my "lip scrub is helpful" hypothesis because it's likely that different people are asking different things. (Some people might, for example, never wear lipstick and want to know if it will be worth it for that one special gala where they're finally going to break out a red pout. Others might use a lip scrub on the regular and want to know if it's worth it to fit it into their daily routine.)
I decided the easiest way to do a test that is helpful for most interested parties was to use a lip scrub on one side of my mouth and compare it to the other half. Because I have no reason to suspect that I use one half of my mouth more than the other half, and because I worried that scrubbing one day would carry over in helpfulness to the next day, I decided to dedicate one half of my mouth to scrubbing for the entirety of the test, rather than switching from side to side.
Before my test, I did not use a lip scrub for one week. Then, I scrubbed one half of my mouth with a lip scrub and applied lipstick over my whole mouth. I applied in the morning, applied nothing to my mouth for the whole day (P.S. NOT RECOMMENDED. I HEART LIP BALM. DRY LIPS HURT.), and then took a picture of my dried up, unhappy lips eight hours later to see which side of my mouth faired better. The test took three days with three different lipsticks.
In the pictures below, the left side of the picture got the scrub, and the right side did not. Warning: ugly end-of-the-day lip pictures ahead.
Lipstick #1: Bite Beauty High Pigment Pencil in Quince
In terms of color saturation, both the left side and right side of my mouth look pretty similar. On the far right corner of my mouth, there is perhaps slightly more fading than there is on the left corner. The big visible difference is that the right half of my mouth has hunks of dead skin that is unattractively coated in lipstick.
Lipstick #2: MAC Party Parrot
Lipstick #3: Kat Von D Everlasting Love Liquid Lipstick in Berlin
Still, for all three lipsticks, the side that had been scrubbed down had less fading and looked generally more visually appealing due to lack of lip gunk polluting the view. The corners of my mouth and the top of my bottom lip were the most affected regions. I feel comfortable, then, concluding that lip scrubs do extend the life of your lipstick, although the effects may be more or less pronounced for certain types of lip colors.