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13.6: Synthetic vs. “Natural” Vitamins

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    Because the role of vitamins is a chemical one, it’s the success or failure of the chemistry which matters. So just as we’re able to judge the amounts of vitamins needed, so also can we evaluate sources of vitamins for potency.

    We can easily answer the old questions about whether the vitamins in foods are different from those made in a laboratory. We can apply simple tests, seeking simple answers to the simple question: Do the vitamins made in the laboratory enable the needed chemical reactions to take place as well as the “natural” vitamins do?

    The purpose of vitamins is for body chemistry, so the absolute test of vitamin potency rests with chemical assays of pertinent biological reactions.

    The results of such assays can be seen on any number of pill bottles and food packages, where the vitamin values are set forth in terms of effective amounts of the vitamins contained in each measure—a pill or a serving. And such labels are closely regulated by Federal law and monitoring.

    The bottom line is vitamin potency. Vitamins don’t function at different levels. They either function or they don’t. Although there can be more than one natural form of a vitamin, whatever form is synthesized in the laboratory has the identical function as the natural model found in food. It’s not just similar. It’s the same. Vitamin C is vitamin C, whether synthesized in a laboratory flask or in an orange.


    Vitamin C supplements that “contain natural C from rose hips” contain mostly laboratory-made vitamin C. Adding a bit of vitamin C from rose hips adds to its allure—and price.


    Wishful thinking and language confusion have muddled these clear-cut truths. Especially, the word synthetic has been corrupted by popular usage. To synthesize means to combine parts to make something. When that something is a vitamin, the end-product of the synthesis must be the vitamin.


    The language problem may have begun with commercial use of the term synthetic rubber during World War II and after. It was really imitation rubber because, while it had some of the characteristics of natural rubber, it wasn’t the same. Synthetic vitamins aren’t imitation vitamins. They are the vitamins—nothing else.


    The making of a vitamin is no less exact a task than the making of a key for a very sophisticated lock. If the key doesn’t fit precisely, the lock won’t open. So must the synthesized vitamin fit a precisely required chemical pattern. If the molecule isn’t just right, it can’t carry out its role.

    We thus have two clear-cut tests for insuring successful vitamin synthesis, both similar to the tests for a well-made copy of a key. First, the vitamin molecule, like a good key, must exactly reproduce the original. Secondly, the synthesized vitamin must work. Just as the key must open the lock, so must the molecule enable the chemical reaction to take place.

    All the forms—regardless of the brand, expensive or not—must be similarly usable, or they wouldn’t be vitamins, merely related chemicals. Whatever the form, what matters is that the working part of the vitamin, the part of the molecule that must fit other molecules to function, is the same. Variations in another part of the molecule are no more important in this respect than are variations in the decorative handles of keys. The key works or doesn’t work, whether the handle is gold or brass.

    What really counts is whether the key moves the tumblers in the lock. It makes no difference if the key is a fancy one stamped Rolls Royce, or is a generic spare made at the local hardware store.

    13-3.png
    Figure 13-3: Natural and synthetic vitamins have the same chemical structure.

    The Sources of Vitamins

    A corollary to unscientific concerns about vitamins being “natural” or synthesized is a large body of myth about vitamins and their special sources. These myths are of three principal kinds.

    • Myth #1: Differences in the source make for different kinds of vitamins.

    The misconception here is distorted, but perhaps derives from a basic truth. In the case of vitamin A, some sources don’t contain the vitamin itself, but instead hold provitamins. These are molecules which the body can easily convert to the vitamins, but which aren’t actually the vitamins themselves. For example, there’s no actual vitamin A in vegetables, such as carrots. But in practical terms, the provitamins in plant foods (e.g., beta-carotene in carrots) can serve the body just as well, because they can be converted to the vitamin by the body.

    • Myth #2: Differences in the source make for a different “quality” of vitamin.

    The basis of this misunderstanding is probably the fact that some foods are richer sources of vitamins than others. Consider the popular fantasy that “natural vitamin C from rose hips” has some special superiority. It doesn’t. Despite the fact that rose hips, the seed pods of the rose, are an extraordinarily rich source of the vitamin, the vitamin C extracted from them is no different from any other. Each milligram of vitamin C taken from rose hips is identical to a milligram of the vitamin derived from oranges, cabbage, or broccoli—or assembled in a pharmaceutical factory.

    • Myth #3: Differences in the source mean that “extras” will accompany the vitamin.

    When vitamin values are shown on a label for vitamin pills, the source from which they are taken has no additional meaning. To believe otherwise is the same as believing that aluminum differs according to whether it’s been extracted from the bauxite ores of Jamaica or taken out of old cans. The successful chemical objective is to purify the aluminum—or the vitamin.

    Yet commercial promotion has tried to popularize the idea that the source determines the quality of the end product, as in “vitamin C from the sunshine tree.” Such ideas are pathetically popular.

    We see similar examples daily with other products. For example, some are convinced that sucrose (table sugar) differs somehow according to whether it comes from sugar cane, or from a sugar beet, or whether it’s grown on the mainland or in Hawaii. But the sucrose which is refined from either cane or beet, no matter where it’s grown, is still sucrose, a precisely defined molecule. The only real difference between these two sugars, since they’re chemically the same, is price and image.

    Foods do differ from one another, of course. If we get vitamin C from Tang (the orange‑flavored drink powder), it holds only the nutrients assembled by the manufacturer. If we get the vitamin C by eating a potato or an orange, we get the other nutrients which nature has included in the food. This is, in fact, one reason why nutritionists generally recommend that we get our nutrients from food rather than dietary supplements.


    This page titled 13.6: Synthetic vs. “Natural” Vitamins is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Judi S. Morrill via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.