I recently got this question:

 but as i look thru your label, i notice that the type of vitamin e you use is the dl-alpha type.  i have always read that this is the type to be avoided at all costs.  can you tell me why you use it?  thanks again.  maria

First, great question!

The answer relies on a nuanced understanding of what vitamin E actually is.  In doing so we’ll talk about the differences between d-alpha tocopherol and dl-alpha tocopherol, and why you don’t need to worry about vitamin E supplementation all that much to begin with.

What It Is

Vitamin E actually isn’t a single identifiable compound.  It’s a class of 8 different compounds that belong to two types of familes: tocopherols and tocotrienols.  Even more, these different pherols and trienols have different versions of themselves that behave differently in your body, bringing the total variety of biologically distinct types of vitamin E into the dozens.

Despite this diversity, there’s one particular type of vitamin E that your body prefers; alpha-tocopherol.  All the versions of vitamin E confer some benefit, but your body is much more likely to absorb alpha-tocopherol than any other by a large margin.  All forms of vitamin E behave as an antioxidant, but alpha-tocopherol provides health benefits unique unto itself.  It acts as a signal transductor within the membrane of your cell walls that make it very important for brain function and fatty acid metabolism.

The Different Types of Alpha-Tocopherol

Alpha-tocopherol has eight different flavors.  They’re technically all the same molecule, but have unique geometries that cause them to behave differently in your body.  The form that’s most readily absorbed is called “RRR” alpha-tocopherol.  The other seven are some combination of R and S alpha-tocopherol. (RRS, RSS, SSS, etc).

Almost all the vitamin E found in food is alpha-tocopherol and will come in two difference flavors:

• d-alpha tocopherol
• and dl-alpha tocopherol

They’ll often be followed with a name like succinate or acetate, but this is immaterial for how it works in your body.  (Hint: it’s all the same).

The difference between d-alpha-tocopherol and dl-alpha-tocopherol is that the “D” kind only contains the RRR type, and the “DL” kind includes all 8 versions of alpha-tocopherol.  Overall the “D” type is preferable but the difference between the two is very small for your health.

Why?

• Unabsorbed vitamin E is excreted as a compound called CEHC, and thus there is no danger due to excess (except for extreme cases)
• On a label Dl-alpha-tocopherol is adjusted so that the stated RDV is on an equal basis with D alpha-tocopherol.  It’s assumed that it won’t absorb as readily and thus you need about twice as much DL-alpha-tocopherol to have the same RDV as d-alpha-tocopherol.
• Your diet, gastrointestinal tract, and lifestyle factors play a very large role in how much vitamin E you actually use, regardless of what type you get in your supplement
• Vitamin E is a good example of a nutrient that needs to be a part of the food you eat, not a supplement you take.

An Inconvenient Truth About Vitamin E Supplements

Vitamin E comes in a variety of forms, all of which are benign, but some of which are more helpful than others. With the exception of extreme cases, none of them cause any harm.

However, when it comes to vitamin E supplements, there’s an opposing, inconvenient truth: most of them don’t do any good.  Vitamin E is essential for your health, but for the general population a vitamin E supplement does not exert noticeable health benefits.  It’s different if you’re deficient, but that’s very rare in a developed country.

Vitamin E needs to come from a meal.

Consider the following:

• Because it’s fat soluble, the absorption of vitamin E can vary from 10-90% depending on whether or not it’s taken with a meal, as well as the fat content of said meal.
• Vitamin E exerts its benefits by complexing with different proteins within your cell, and thus needs to be consumed with other nutrients like selenium to have any effect
• Many foods with very small amounts of vitamin E exert greater effects within your body than a pill that has 5000% (or whatever) of your RDV because it delivers vitamin E with the appropriate food matrix.
• Because vitamin E is deposited in fat, it’s possible its utilization also depends on a well functioning endocrine system that mobilizes and stores fat appropriately.  (Note: I’m theorizing on this point.  NOT to be taken as verifiable fact).

These effects wash out the particular details of how much or what kind of vitamin E you read on a label.  In fact, I might even go so far as saying that your gross intake of vitamin E means very little for someone on a western diet.  (Although there are obvious exceptions to what I just said so use common sense if you think this might apply to you).

Don’t Buy Vitamin E Supplements

I appreciate this question, but I do not feel the presence of d-alpha-tocopherol or dl-alpha-tocopherol is a useful signal for the quality of a supplement.  In fact I think vitamin E supplements in general are a waste of money.  I’ve written before that whole food supplements trump synthetics because of the precise issues surrounding vitamin E supplements.   The raw amount consumed has little to do with how much good you’re actually doing your body.

References

Brigelius-Flohe, Regina, et. al. “Vitamin E: Function and Metabolism”

URL: http://www.ncbi.nlm.nih.gov/pubmed/10385606

Jeanes, Yvonne, et. al. “The absorption of vitamin E is influenced by the amount of fat in a meal and the food matrix.”

URL: http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=915456

Wu, J.D., et. al. “Vitamin E Metabolism”

URL: http://www.sciencedirect.com/science/article/pii/S009829970700009X

Wang, X, et. al. “Vitamin E and Its Function in Membranes”

URL: http://www.sciencedirect.com/science/article/pii/S0163782799000089

Borel, P. “Factors affecting intestinal absorption of highly lipophilic food microconstituents (fat-soluble vitamins, carotenoids and phytosterols).”

URL: http://www.ncbi.nlm.nih.gov/pubmed/12964802

Sikbin, Simin, et. al. “Vitamin E Supplementation and In Vivo Immune Response in Healthy Elderly Subjects:  A Randomized Controlled Trial”

URL: http://jama.jamanetwork.com/article.aspx?articleid=415853