Vegetable Oils are Natural Sources of Vitamin E
~ November 1997 No.22 ~
Many people argue that it is not necessary to take pills or capsules of vitamins because you can get your vitamins and much more from the foods you normally eat. It is hard to argue against the "natural is better" point of view. It is of course very difficult for those of us who are forced to eat on the run and have to eat only what we can hold in one hand to get our share of essential nutrients each day. Added to this is the fact that when studies show health benefits of such things as vitamins, it is often at intake levels beyond what is normally accepted as adequate for proper nutrition.
Vitamin E is a nutrient that is constantly in the news these days, mainly because of its antioxidant properties. The whole topic of vitamin E is complicated by the fact that there are eight chemically related compounds - called isomers - that are often lumped together and called vitamin E. d-alpha-tocopherol is the shorter and easier way of referring to [2R-2R*(4R*,8R*)]-3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1- benzopyran-6-0l or vitamin E. In many of the foods we eat we find alpha-tocopherol and in addition beta-tocopherol, delta-tocopherol, gamma-tocopherol and esters of alpha-tocoperol. All of these compounds have "vitamin E activity" in the classical sense, but are not as potent as alpha-tocopherol. However, as far as its antioxidant effectiveness goes, alpha-tocopherol is often not as good as the other forms of vitamin E. It is widely accepted that delta is a better antioxidant than gamma which is better than beta which is better than alpha.
So how can you increase your intake of vitamin E? Generally oilseeds (canola, soybean, corn, safflower and cottonseed ) and their products (vegetable oils or margarines) are good sources of vitamin E. But as the table below shows, vegetable oils contain a mixture of the different chemical forms of tocopherol.
Most food labels are not detailed enough to report the different isomers of vitamin E and so the value quoted on the label is either for only alpha-tocopherol or it may be for the total of all vitamin E compounds. It depends on how the analyses were carried out. It is probably best to use a variety of oils in the diet to make sure that you are getting at least some of all the different forms of vitamin E. Vegetable oils still are one of the best sources of vitamin E in the diet.