Natural Vitamin E is called D-Alpha Tocopherol while Synthetic is known as Dl-Alpha
Tocopherol (D=Natural, Dl= Synthetic) Natural Vitamin E is extracted from 100% Natural sources like Soya, Sunflower & Rapeseed, whereas Synthetic Vitamin E is chemically prepared in chemical plants from petrochemicals namely Isophytol & Tri Methyl Hydroquinone D-Alpha Tocopherol molecule has one single molecular structure (R-R-R), whereas Dl-Alpha Tocopherol molecule is made up of eight different structures (Stereoisomers). Out of these eight stereoisomers only one resembles natural Vitamin E form. Our body recognizes only Natural Vitamin E molecular form. Thus D-Alpha Tocopherol has 100% Bio-availability i.e. it is completely absorbed & utilized by human body. Thus for Synthetic Vitamin E the Bio-availability is mere 12.5% as only one molecular structure (Stereoisomer) out of eight (1/8) which is similar to D-Alpha Tocopherol is recognized by body. Rest seven forms are excreted from the body which is nothing but unwanted burden. Even in terms of IU (International Unit) which is measurement unit of Alpha Tocopherol, Natural form is superior.
1 mg of D-Alpha Tocopherol = 1.49 IU
1 mg of Dl-Alpha Tocopherol = 1.10 IU