Is using lemon juice on your face safe?

Ah, Lemons. Pinterest loves them. So does grilled salmon. Lemon juice is often used in DIY skin treatments for brightening, acne, exfoliation and the benefits of vitamin C. There are usually two stances on lemon in skin care: totally love it or do not use them ever! I fall in the “do not use them ever” category because, SCIENCE. 

The Chemistry of Lemon Juice

Let’s take a trip back to chemistry class for a refresher on ph, but in terms of skin care. Potential of hydrogen (ph) is the measure of how acidic or alkaline a product is. The scale ranges from 1, being the most acidic and 14, being the most alkaline. Ph of 7 is considered neutral and the optimal ph of the skin is around 4.5-6.

The ph of lemon is around a 2 being highly acidic. When lemon is applied to the skin in a DIY treatment it immediately disrupts the skin’s protective acid mantle layer. It causes a significant amount of irritation, redness, and inflammation. Skin that is too acidic is overall more sensitized and may make acne worse.

Lemon Juice + The Sun

Citrus fruit is also phototoxic, meaning if you go out in the sun with your DIY toner on your skin it could cause blistering, rashes or chemical burns. Even diluted with water! There is also a phenomenon nicknamed “margarita dermatitis.” It’s most commonly seen after vacations when people have been sipping on drinks that lemons/limes are squeezed into. The citrus is accidentally squirted on the skin and when mixed with the sun = pigmentation and/or rash and could even turn into blisters. I won't post photos and save you the misery. 

Risks Outweigh Benefits

Now, the argument that lemons are natural, a good source of vitamin C and a light peel. Yes, lemons are natural, and so is poison ivy. It doesn’t mean every natural thing is good for the skin. The vitamin C in citrus fruit is citric acid and is NOT the same type of vitamin C that is in vitamin C serum. It's mainly l-ascorbic acid or sodium ascorbyl phosphate. As for thinking of lemon juice as a light peel, there are many factors to consider. Unlike skincare products fruits aren’t precise, how do you really know how much acid is in a lemon? It will completely vary per the fruit. In a facial peel, they are formulated specifically for the skin. There are also post peel steps involved that neutralize the acid bringing it back to the correct ph for the skin which in turn keeps the skin safe.

Some DIYs are fabulous, this is one I would recommend staying away from!