This post about tallow skincare is by James Giles, founder of True Origin Skincare.

We all know synthetic fragrance is extremely problematic. Most of the non-toxic category, especially tallow, jumped to essential oils, and that isn’t much better. There are two problems with putting essential oils in a moisturizer you use every day. The first is phototoxicity. The second is oxidation.

I make tallow skincare, so I have a stake in this. I started formulating after an undiagnosed autoimmune condition left me reacting to nearly everything on the shelf, including the natural options. So I start with the chemistry and leave the marketing for last.

Why tallow brands reach for them

Rendered beef fat smells like beef fat. Once the category moved off synthetic fragrance, a few drops of lavender, frankincense or citrus became the easy way to cover it. Most tallow balms are built this way: 80% to 90% tallow, an oil or two, and an essential oil for scent. The scent is doing more marketing work than anything else in the jar.

Problem one: phototoxicity

Cold-pressed citrus oils, including bergamot, lemon, lime, grapefruit and bitter orange, contain compounds called furanocoumarins. On skin that sees sunlight, furanocoumarins react with ultraviolet light and cause a burn-like reaction. It can leave dark patches that last for months.

This is well documented enough that the International Fragrance Association caps bergapten, the main furanocoumarin, at 15 parts per million in leave-on products. The Cosmetic Ingredient Review sets limits across the citrus oils for the same reason. A formulator who knows those limits can stay under them, but nothing requires a small brand to test for it, and most customers have never heard the word.

Phototoxicity can at least be designed around. The second problem cannot.

Problem two: oxidation

The compounds that give essential oils their scent are terpenes, and terpenes react with oxygen. The moment the oil meets air, it starts changing. Linalool and limonene, found in lavender, citrus and most popular blends, oxidize into hydroperoxides, and hydroperoxides are far stronger skin allergens than the oil was when it left the still.

This has been established since the 1990s. A 2019 study of 821 dermatitis patients found high rates of reactions to oxidized limonene and oxidized linalool, most of them clinically relevant. A separate paper on lavender found that its main compound, linalyl acetate, becomes a potent allergen as it oxidizes. Europe’s standard patch test series now includes these oxidized compounds next to nickel and formaldehyde.

Brands that use essential oils often answer this with fresh sourcing. Fresh means it arrived that week. It says nothing about when it was distilled. Before it reaches your bathroom, that oil has been distilled, packaged, shipped to a supplier, stored, shipped to the maker, mixed, jarred, stored again and shipped to you. It has been meeting air for weeks. Then you open that jar every morning for months, and the hydroperoxides keep forming the whole time.

The damage is slow. That is why people miss it. Most people use a lavender balm for months or years with no trouble. Then the skin reacts one day, and from then on it reacts to that compound, often in other products too. Nobody connects it to the balm they have trusted for years.

Grade does not change this. Neither does organic certification or the word “therapeutic” on the bottle. Terpenes oxidize when they are exposed to air.

What tallow does well, and what it does not

Tallow’s fatty acids are close to the ones in human skin, so it absorbs well and leaves skin soft. It is a great lipid base. It is not a vitamin source. Most tallow brands sell on vitamins A, D, E and K, but third-party testing, whatever the rendering method, shows those vitamins come back in trace amounts, nowhere near effective doses.

A formula that is almost all tallow does one job. It holds moisture in. Anything more has to come from other ingredients, at amounts high enough to matter. That gap is part of why we formulate without essential oils. The room goes to the rest of the formula.

How to read a tallow skincare label

Five checks cover most of what to look for in tallow skincare:

• Scan for essential oils by name. Lavender, tea tree, frankincense, eucalyptus, peppermint, orange, lemongrass and “essential oil blend” all count.
• Be most careful with citrus oils. They carry the phototoxicity risk on top of oxidation.
• Treat “fragrance,” “parfum” and “natural fragrance” the same way. None of them tell you what is inside.
• Watch for linalool, limonene, citral, geraniol and eugenol near the end of the list. These are the compounds regulators make brands disclose.
• Check what sits next to the tallow. If the second ingredient is an aromatic oil, you are buying mostly fat and scent.

When I built our Deep Hydration Whip, I left essential oils out completely, along with synthetic fragrance. The scent comes from organic rose petals, vanilla bean and marshmallow root infused into the tallow itself. Nothing is distilled, so no concentrated terpene fraction is sitting there oxidizing. Alongside the tallow are castor, squalane, jojoba, meadowfoam, rosehip and sea buckthorn, each chosen for a specific job.

It is recommended by integrative and functional doctors and carried in holistic medical clinics. Those practices screen what goes on their patients’ skin, and a leave-on product scented with essential oils is one of the first things they flag.

If you already use a tallow balm you like, check the label tonight. If it lists any of those oils and your skin has started acting up, the balm is worth a closer look.

Sources

• International Fragrance Association. IFRA Standard: Citrus oils and other furocoumarins containing essential oils, Amendment 49, 2020. ifrafragrance.org/standards/IFRA_STD_089.pdf
• Cosmetic Ingredient Review. Safety Assessment of Citrus-Derived Ingredients as Used in Cosmetics, 2013. cir-safety.org/sites/default/files/citrus2013slr_final%20for%20posting.pdf
• DermNet. Contact allergy to limonene and linalool. dermnetnz.org/topics/contact-allergy-to-limonene-and-linalool
• Contact sensitization to hydroperoxides of limonene and linalool: results of consecutive patch testing and clinical relevance. Contact Dermatitis, 2019. pubmed.ncbi.nlm.nih.gov/30378131
• Autoxidation of linalyl acetate, the main component of lavender oil, creates potent contact allergens. Contact Dermatitis, 2008. pubmed.ncbi.nlm.nih.gov/18154552

About the author

James Giles, founder of True Origin Skincare

James Giles is the founder of True Origin Skincare, an all-natural, non-toxic skincare brand from Utah. He builds every product with no essential oils or synthetic fragrance.

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