Inside the pH lip tint obsession

Behind the ‘magic’ of colour-changing lip products lies a truth the beauty industry rarely spells out

- Tejashee Kashyap

By now, you've probably seen them everywhere — pH-changing lip products have become the kind of phenomenon in the beauty world.

They're marketed as a magical in-between: not quite makeup, not quite skincare, but a personalised tint that promises to deliver the perfect shade. But beneath this glossy narrative lies a truth the beauty industry hasn't exactly been eager to spotlight: for most people, these products create the same bright bubblegum pink, regardless of skin tone, undertone, or chemistry.

“Honestly, the biggest misconception is that these pH-changing colours shift according to your mood. That's not science, that’s a marketing gimmick to sell products. Your lips aren't mood rings,” rightfully says Arshia Kaur Vijan, a cosmetic scientist and also the founder of beauty brand, Tint Cosmetics.

But here's the inside joke in the cosmetics industry: the trick isn’t your chemistry. It’s theirs. These products are not reacting to your unique pH. “It comes down to one ingredient: Red 27 (also known as Acid Red 92). In its acidic form, this pigment is completely colourless. But the moment it hits a slightly basic environment — around pH 6 to 7, like your lips — it snaps into a bright, bubblegum-pink shade,” she reasons. “That's why these products seem to create a personalised tint, even though the colour is usually the same for everyone.”