lemon juice

The juice from the citrus fruit lemon, often touted in the world of skin care as being a natural option for brightening skin. The truth is that lemon juice is highly acidic, with a very low pH that's exceedingly sensitizing to skin. Lemon juice has a pH of 2, and comparing an ingredient with that pH to just one number up (that being pH 3) is like the difference between a minor tremor in the ground and a catastrophic earthquake.

Lemon juice applied to skin can cause photosensitivity, which is due to a volatile fragrance chemical known as limonene, which is abundant in lemon juice.

Bottom line: There's no research showing that lemon juice has a positive effect on brightening an uneven skin tone, yet it's clear this ingredient is a potent skin sensitizer. Given its antioxidant content, lemon juice has its benefits, but far better to consume it orally than apply it topically.

See lemon lemon oil

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About the Experts

Paula Begoun is the best-selling author of 20 books about skincare and makeup. She is known worldwide as The Cosmetics Cop and creator of Paula’s Choice Skincare. Paula’s expertise has led to hundreds of appearances on national and international radio, print, and television including:

The Paula's Choice Research Team is dedicated to busting beauty myths and providing expert advice that solves your skincare frustrations so you can have the best skin of your life!