Catherine’s Concerned About Sunscreen Efficacy: I’ve heard that when sunscreen/sunblock separates, it`s no longer good. That shaking it up to remix it is basically wasted effort and applying it will do no good at all. Is this true? Can sunscreen go bad?
The Left Brain Concurs:
bad sunscreenSunscreen formulations are very sensitive creatures. Most UV absorbers are oil soluble, which means they have to be carefully emulsified to form stable mixtures with water. If the oil and water in the formula are not properly coupled together, the whole formula can go to hell pretty quickly. Here are 3 warning signs that your sunscreen has gone sour:

1. Weird consistency

The consistency of the product has changed over time and now it’s too thick or too thin to spread properly. The spreadability of sunscreens is crucial to proper application and coverage. If it doesn’t spread right, it won’t work right.

2. Crystalization

The active ingredient has crystallized out, making the lotion feel gritty. When this happens the product is completely worthless. You can’t fix that by shaking.

3. Separation

The product has separated into two different layers. Also not good. At worst, the active ingredient will partition into the oil phase and shaking it may or may not re-suspend it properly. At best, the water-resistance of the product may be compromised and it will wash off too easily. Either way, it`s really not worth using. Go buy a fresh bottle.

The Beauty Brains Bottom Line:

Given the importance of good UV protection, don’t take chances with a bottle of sunscreen that you think may be bad. Most manufacturers of sunscreen products like Coppertone, Himaya, Ocean Potion, and even Jack Black, should gladly refund your money or offer you a replacement if you have a problem.

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5 Responses to “3 Ways To Tell If Your Sunscreen Is Bad”

  1. sarah Says:

    does it matter whether you put moisturizer on before vs. after your sunscreen?

  2. Left Brain Says:

    You probably want to put the moisturizer on before the sunscreen. This will ensure that you get a consistent film spread on with the sunscreen.

  3. thebeautybrains.com » Don’t Ruin Your Nails By Using the Wrong Sunscreen Says:

    [...] sunscreen ingredients can be tough to dissolve (by the way, if you haven’t read our post on 3 Ways to Tell if Your Sunscreen is Bad, this might be a good time to do [...]

  4. missa Says:

    What if you have a sunscreen that says “shake well before using”?

  5. thebeautybrains.com » Blog Archive » 4 Ways To Tell If Your Cosmetic Has Expired Says:

    [...] If it’s a regular product, like the Matrix example mentioned above, you probably don’t have much to work about. But some active ingredients are a bit finicky, and those products can expire much sooner. Products like Babor’s Intelli-zyme and even sunscreens are much more delicate. Click here if you want to read our previous post about how to tell if your sunscreen’s gone bad. [...]

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