With tons of mascara out there, both waterproof and not, I always assumed personal preference was the driving force behind purchases. I have a pal who purposely stocks a water-repellent tube during the cold months (and for sappy movie dates) whereas others wear only waterproof even on happy days. So, what's the big difference?

Well, as I embarked on my latest research mission, I hoped for an easy answer . . . but no dice. It seems likely that what makes makeup waterproof is the presence of fats, oils, or waxes, as all three of those are hydrophobic — that is, resistant to moisture. (It makes sense that cosmetic companies would keep exact mixtures a secret, as competitors would want to include whatever worked best.)

But speculation is never that satisfying for Detective Bella so next I set out to compare the ingredients of one of my favorite mascaras, Diorshow vs. Diorshow Waterproof. Get my results when you read more.

Tackling just the first five ingredients in each product, I found a few differences. In its top five ingredients alone, the waterproof version had three waxes (beeswax, candelilla wax, and carnauba wax), water, and isododecane, a mixture of highly branched isoparaffins. However, the regular Diorshow had only one wax in the top five (beeswax). In this case, speculation proves true: Wax helps this waterproof mascara stand the test of time.

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