What does your skin, yogurt, and lactic acid have to do with each other?

A friend gifted me some natural-ish bath & body products (face masks, creams, oils, etc). This was a real treat, as I usually make a lot of these things at home (of course, to avoid synthetic additives and greenwashed labels).

One thing that stood out was a “lactic acid treatment” for skin. It boasts exfoliation, removing dead dull surface skin, and restoring clarity and smoothness. It brightens dark spots and discoloration and instantly plumps the look of fine lines and wrinkles. Wow, that sounds great, right?

When I hear the word “lactic acid”, I immediately think about dairy and fermentation. I don’t generally think about skin… but now I am!

I’ve used yogurt and kefir in face masks before, but I was doing it for the probiotics and to balance pH. Since your skin is the largest organ on your body, having a good microbiologic balance is so important. But now, I have another reason – lactic acid!!! 

Read on for more info about lactic acid, yogurt, and using it on your skin.

The science behind what lactic acid does for your skin

Lactic acid is an alpha-hydroxy acid (AHA) that is commonly used in skincare products and treatments. It is derived from sources such as sour milk, fruits, and vegetables (more on that later). Lactic acid has several beneficial effects on the skin due to its chemical properties and interactions with the skin's physiology. Here are some key aspects of lactic acid's effects on the skin:

• Exfoliation: Lactic acid acts as a chemical exfoliant, meaning it helps to remove dead skin cells from the surface of the skin. It does this by loosening the bonds between skin cells, allowing them to be easily shed. This exfoliating action helps to smooth the skin's texture, improve its tone, and promote a more youthful appearance.
• Moisturization: Lactic acid has humectant properties, which means it helps the skin retain moisture. It attracts water molecules from the environment and draws them into the skin, hydrating and plumping it. This moisturizing effect can be particularly beneficial for individuals with dry or dehydrated skin.
• Stimulates collagen production: Lactic acid stimulates the production of collagen, a protein that provides structural support to the skin. Collagen helps maintain the skin's elasticity and firmness, and its production tends to decline with age. By promoting collagen synthesis, lactic acid can help improve the skin's elasticity, reduce the appearance of fine lines and wrinkles, and contribute to a more youthful complexion.
• Improves skin tone and hyperpigmentation: Lactic acid has the ability to inhibit the production of melanin, the pigment responsible for skin color. By doing so, it can help reduce the appearance of dark spots, uneven skin tone, and hyperpigmentation caused by factors such as sun damage or acne scars. Regular use of lactic acid can lead to a more even, radiant complexion.
• Enhances product penetration: Lactic acid also has the ability to enhance the penetration of other skincare products. By exfoliating the outermost layer of the skin, it allows active ingredients in serums, moisturizers, or treatments to penetrate more deeply and effectively, maximizing their benefits.

Natural sources for lactic acid

Lactic acid can be found naturally in various food sources. Here are some examples of natural sources of lactic acid:

• Fermented dairy products: Lactic acid is commonly present in fermented dairy products like yogurt, kefir, and buttermilk. The bacteria used in the fermentation process convert lactose (milk sugar) into lactic acid, giving these products their characteristic tangy taste.
• Fermented vegetables: Lactic acid fermentation is also used to preserve and flavor vegetables. Sauerkraut, kimchi, pickles, and other fermented vegetables contain lactic acid produced by the fermentation process.
• Fruits: Certain fruits naturally contain lactic acid. For example, sour cherries, apples, and grapes have lactic acid content, although in relatively small amounts compared to other sources.
• Fermented beverages: Some traditional fermented beverages, such as kombucha and certain types of fruit juices, can contain lactic acid produced during the fermentation process.
• Sourdough bread: Sourdough bread is made by fermenting a mixture of flour and water using wild yeasts and bacteria. Lactic acid is one of the byproducts of this fermentation process, contributing to the unique flavor and texture of sourdough bread.
• Some types of meat and fish: Lactic acid can also be produced during the fermentation of certain types of meat and fish. Examples include traditional cured and fermented meats like sausages or fish sauces like Thai fish sauce.

Should I put any kind of food containing lactic acid on my skin?

Well, of course the only person who can answer this question is you! At Miller’s Bio Farm, we 100% believe in the right to choose what you consume or put on your body.

That being said, although the natural foods listed above all contain lactic acid, it might not be the best idea to use them directly on your skin. I mean, I’ve never heard of a sourdough mask or kombucha serum or a hot salami treatment. But… I’ve heard of yogurt or kefir being used for skincare, and I’ve done it personally myself with great results. 

A grand majority of the internet will likely tell you that store bought skincare products are the only safe source of lactic acid for skin. But, if you’re here reading this, then you likely know that’s absolutely not true. 

Sure, skincare products use lactic acid that’s synthetically derived and produced through controlled fermentation processes specifically for cosmetic use. But, on the other hand, they contain synthetic ingredients and unknown additives that you may want to avoid. Plus, making skincare products at home is so much more affordable than buying them pre-made.

The amount of lactic acid in yogurt or kefir vs store bought beauty products

The lactic acid treatment that I was gifted contains 5% lactic acid, and it seems the same is true for similar products. In comparison, yogurt has about 0.9% lactic acid and kefir has about 1%. 

So, yogurt and kefir contain a lot less lactic acid than beauty products. What does that mean? To get the results of the store bought counterpart, you need to use it more often. 

For us “natural folks”, this is nothing new. For example, if you take an antibiotic, it’s super powered and you need 1-2 pills per day. But, if you opt for a natural antibiotic like garlic or colloidal silver or oregano, you need more doses more often. 

Other benefits of using yogurt or kefir on your skin

You’ll get all the benefits of using lactic acid on skin listed above PLUS more:

• Moisturization: Yogurt and kefir contain natural fats and proteins that help hydrate and moisturize the skin. They can be particularly beneficial for individuals with dry or dehydrated skin, providing a boost of moisture and helping to improve skin elasticity.
• Exfoliation: The lactic acid helps with exfoliation, but the natural enzymes in yogurt and kefir also gently exfoliate the skin. They help to remove dead skin cells and promote a smoother complexion, improving the skin's texture and brightness.
• Acne treatment: Yogurt and kefir have antimicrobial properties that can help inhibit the growth of acne-causing bacteria. Applying yogurt or kefir topically may assist in reducing acne breakouts and calming existing blemishes.
• Supporting the skin's natural barrier: Probiotics can enhance the skin's natural protective barrier by reinforcing the skin's defense mechanisms. This can help strengthen the skin's ability to retain moisture, protect against environmental aggressors, and prevent the penetration of harmful microorganisms.
• Calming skin inflammation: Probiotics have anti-inflammatory properties that can help soothe and calm irritated or inflamed skin. By reducing inflammation, they can assist in managing conditions such as acne, rosacea, or eczema.
• Balancing the skin's pH: The acidic pH of yogurt and kefir helps maintain the skin's natural pH balance, which is important for a healthy skin barrier function. By preserving the optimal pH level, probiotics in yogurt and kefir can promote overall skin health and prevent the overgrowth of harmful bacteria.
• Regulating sebum production: Some studies suggest that certain strains of probiotics can help regulate sebum production in the skin. Excessive sebum production can contribute to oily skin and acne, so balancing sebum levels may lead to improved skin clarity.

Recipes for homemade yogurt or kefir masks

If you’re looking to avoid chemical-laden beauty products or simply save money by making body products at home, here are a few simple yet amazing recipes. For each recipe, simply mix the ingredients together and apply to clean, dry skin. Let sit for 15-20 minutes before rinsing with lukewarm water.

Antibacterial Yogurt & Honey Mask

Add the antibacterial and hydrating benefits of honey.

• 2 tablespoons plain yogurt (or kefir)
• 1 tablespoon raw honey

Anti-Inflammatory Yogurt & Turmeric Mask

Add the anti-inflammatory and antibacterial benefits of turmeric.

• 2 tablespoons plain yogurt (or kefir)
• 1 tablespoon turmeric

Purifying Yogurt & Activated Charcoal Mask

Add the cleansing and purifying properties of activated charcoal.

• 1 tablespoon plain yogurt (or kefir)
• 1 capsule of activated charcoal 

Exfoliating Yogurt, Honey & Oats Mask

Add the exfoliating benefits of ground oats and the antibacterial and hydrating benefits of honey. 

• 2 tablespoons plain yogurt (or kefir)
• 1 tablespoon raw honey
• 1 tablespoon finely ground oats (or almonds)

If you’d like, you can add 1-2 drops of essential oil to the above recipes for fragrance and added benefits:

• Lavender Essential Oil: Soothes and calms the skin, promotes relaxation, and has antibacterial properties.
• Tea Tree Essential Oil: Known for its antibacterial and antifungal properties, helps fight acne and blemishes, and can aid in controlling excess oil.
• Frankincense Essential Oil: Helps promote skin regeneration, reduce the appearance of wrinkles and fine lines, and has a rejuvenating effect on the skin.
• Rosehip Essential Oil: Rich in vitamins and antioxidants, helps reduce scars, hyperpigmentation, and signs of aging, and provides deep hydration to the skin.
• Chamomile Essential Oil: Known for its calming and anti-inflammatory properties, soothes sensitive and irritated skin, and can help with conditions like eczema and rosacea.
• Geranium Essential Oil: Balances sebum production, tightens the skin, and promotes a healthy complexion. It is also known for its uplifting aroma.
• Ylang Ylang Essential Oil: Helps balance oil production, improves skin elasticity, and has a calming and uplifting effect on the mind.
• Neroli Essential Oil: Regenerates and rejuvenates the skin, reduces the appearance of scars and stretch marks, and has a beautiful floral fragrance.
• Carrot Seed Essential Oil: Rich in antioxidants and vitamins, promotes skin rejuvenation, helps improve skin tone, and provides natural sun protection.
• Patchouli Essential Oil: Known for its cell-renewing properties, helps with skin conditions like acne and eczema, and has a grounding and earthy aroma.

*It's important to note that while lactic acid offers several benefits for the skin, it can also cause sensitivity, especially in higher concentrations or for individuals with sensitive skin. It is recommended to perform a patch test before using lactic acid products and to start with lower concentrations, gradually increasing if tolerated well. Consulting with a dermatologist or skincare professional is always advisable to determine the best approach for your specific skin needs.