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Vitamin E (Tocopherols)

Home crafters often recommend using Vitamin E as an antioxidant to lengthen the shelf life of lotions, soap, balms, etc.

Vitamin E as sold as a health supplement normally contains alpha-tocopherol (α-tocopherol) alone or a blend of alpha-tocopherol and gamma-tocopherol (γ-tocopherol). Some Vitamin E supplements contain mixed tocopherols, meaning alpha-tocopherol and gamma-tocopherol blended with the six other chemicals found in the tocopherol family.

It is important to realize the one chemical found in all Vitamin E supplements is alpha-tocopherol.

Vitamin E is vital for good health, and it is certainly easy to buy and use. Unfortunately, research shows the alpha-tocopherol found in Vitamin E is not a good choice for lengthening the shelf life of fats, soap, or other personal care products.

Kevin Dunn, author of the book Scientific Soapmaking, found Vitamin E in soap did not work any better to prevent oxidation than no additive at all. (1)

Other research has found higher levels of alpha-tocopherol in fats can increase the rate of oxidation (an effect called pro-oxidation). (2) In other words, too much alpha-tocopherol can shorten the shelf life of a fat, not lengthen it.

Many fats naturally contain tocopherols, including wheat germ, sunflower, safflower, canola, corn, and soybean. (3) These oils are often used by small-scale producers to make soap and other bath and body products.

The alpha-tocopherol content of these fats must be measured to determine the correct dose of Vitamin E to add if you want to use it as an antioxidant. This measurement is not something a typical small-scale producer can do, so it does not make a lot of sense for small-scale makers to use alpha-tocopherol as an antioxidant in their fats and other products. Other alternatives include --

Gamma-tocopherol (γ-tocopherol) did not show a pro-oxidant effect. (2,5) It can also be a more effective antioxidant in fats than alpha-tocopherol. (4,5)

ROE (rosemary oleoresin extract) has a good track record of preventing oxidation in stored fats and soap. ROE can be pro-oxidant at higher dosages, but the antioxidant chemicals in ROE are not naturally present in fats. The correct dose of ROE is simply a matter of careful weighing.

 

References

(1) Dunn, K. Scientific Soapmaking. Clavicula Press. 2010. Chapter 19.

(2) Huang, S. W., Frankel, E. N., & German, J. B. (1994). Antioxidant activity of α- and γ-tocopherols in bulk oils and in oil-in-water emulsions. Journal of Agricultural and Food Chemistry, 42(10), 2108-2114. https://ucdavis.pure.elsevier.com/en/publications/antioxidant-activity-of-%CE%B1-and-%CE%B3-tocopherols-in-bulk-oils-and-in-o

(3) Vitamin E fact sheet for health professionals. Version: February 28, 2020. https://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional

(4) Seppanen, C.M., Song, Q. and Saari Csallany, A. (2010), The Antioxidant Functions of Tocopherol and Tocotrienol Homologues in Oils, Fats, and Food Systems. J Am Oil Chem Soc, 87: 469-481. https://doi.org/10.1007/s11746-009-1526-9 Source: https://aocs.onlinelibrary.wiley.com/doi/abs/10.1007/s11746-009-1526-9

(5) Lampi, A., Kataja, L., Kamal-Eldin, A. et al. Antioxidant activities of α- and γ-tocopherols in the oxidation of rapeseed oil triacylglycerols. J Amer Oil Chem Soc 76, 749–755 (1999). https://doi.org/10.1007/s11746-999-0171-7. https://link.springer.com/article/10.1007/s11746-999-0171-7