The anti-aging, dark spot fading, and acne healing benefits of AHAs have been known for centuries. Cleopatra used to bathe in sour milk to get the youthful benefits of lactic acid, which is a popular AHA.Science tells us they work by a process of chemical exfoliation and new cell growth which leaves your skin looking younger, brighter, and with fewer signs of aging. AHAs fade hyperpigmentation, heal acne and rosacea, and get your skin glowing. We’ll help you find the right pH and concentration so you can get to that sweet spot of results without irritation. This is your Ultimate Guide for understanding the what, why, and how of AHAs so you can get the best formula for your skin type, without irritation.