As a holistic veterinarian, I feel it is incredibly important to take the whole
animal into consideration when it comes to nutrition. And, whenever practical, my
preference is to provide nutrients, minerals and vitamins in their natural forms.
In this post, I’d like to talk to you specifically about vitamin E, to review both the strengths and weaknesses
of natural and synthetic forms.
Vitamin E is an incredibly complex and important nutrient that, among other things,
functions as an antioxidant. Antioxidants are naturally occurring nutrients that
promote health by slowing the destructive aging process of cells (a breakdown called
“peroxidation”). In peroxidation, damaged molecules known as free radicals steal
pieces from other cells, like fat, protein or DNA. The damage can spread, damaging
and killing entire groups of cells. While peroxidation can be useful to destroy
old cells or germs and parasites, when left unchecked, free radicals produced by
peroxidation also damages healthy cells. Antioxidants can help to stem the tide
of peroxidation, thus stabilizing free radicals.
Antioxidants like vitamin E are crucial to the health of companion animals of any age.
They can improve the quality of the immune response and the effectiveness
of vaccines in young pets, and help maintain a vital immune system in seniors.
Vitamin E occurs in one of two forms, either natural or synthetic. Natural vitamin
E is a collection of eight chemically unique compounds that are derived from plants,
including four tocopherols and four tocotrienols. More commonly used and less expensive,
synthetic vitamin E is one compound – alpha-tocopherol.
For me, the choice of using natural or synthetic vitamin E in my formulas couldn’t
be clearer, and neither could the evidence. The synthetic form of vitamin E is not
as active or easily absorbed as the natural form of vitamin E. The molecular structure
of vitamin E determines how well the body can utilize it. In human trials, researchers
found that proteins in the liver specifically select the natural form of vitamin
E and largely ignore the synthetic form. In a Japanese study, scientists found that
it took three times the amount of synthetic vitamin E to equal the blood levels
of natural vitamin E. In the U.S., researchers found that body tissues and blood
retained far higher levels of natural vitamin E versus synthetic. In addition, synthetic
alpha-tocopherol vitamin E has only half the vitamin activity of the natural alpha-tocopherol
Why is there such a difference between synthetic and natural forms of vitamin
E? The key to understanding how the body absorbs these two types differently lies
on the molecular level. The cellular structure of mammals more easily recognizes
natural forms of vitamins. And cellular proteins and blood plasma bind to natural
forms more readily than their synthetic counterparts. Unfortunately, synthetic vitamins
are cheaper and, therefore, are more prevalent in many products on the market today.
So, how can you determine if the products you are using contain the synthetic or natural form of vitamin E? Simply check out the ingredient labels! Natural vitamin E is listed as a-tocopherol acetate, d-alpha tocopherol, d-alpha tocopheryl acetate or d-alpha tocopheryl succinate. Alternately, synthetic forms of vitamin E are labeled with a “dl-“ prefix.
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