Sometimes it is quite frustrating to meet a new wonderful person, and find out that we do not speak the same language. It is really a shame! Just think about all the important facts we are not able to share because of a language gap!
This is the way that sometimes scientists feel when what they say is misunderstood: frustrated. It is nobody's fault but the tradition of using words to mean something different according to the context. To illustrate this point, I will give a short list of terms which are commonly used by scientists in a completely different meaning than the ordinary language:
Organic: we've seen this before. For a chemist, organic simply means that something contains the chemical elements carbon and hydrogen, with some oxygen, a little sulphur, some phosphate and of course nitrogen. Methane gas is best known for its use for heating and for cooking. It is hard to think of the methane gas as organic, but strictly speaking, methane is the prototype of the family of alkanes. But nowadays it is possible to buy organic produce, and eggs, and even organic meat! For the vast majority of people, "organically grown" means that something has been produced without the help of man-made fertilizers and pesticides, using manure as fertilizer. For a chemist, regular meat and produce are just as organic as "organic" ones, since they contain all the above mentioned elements. I wouldn't like to eat feldspar*, no thanks!
Chemicals: this is one of my favourite misunderstandings. In chemistry, we define a chemical compound whenever we have an homogeneous substance of which we can define the exact chemical characteristics, such as melting point, composition, if we're lucky the structure. In the collective mind, a chemical usually sits in a purified form on a shelf in a laboratory. So it is hard to see why vanillin, extracted from the cured vanilla pod, is considered a chemical compound** by a chemist. According to definition, though, vanillin's chemical characteristics are well defined, including its structure. Vanillin can also be easily synthesized in a lab (and it is absolutely identical to the one synthesized by the plant). Another very common chemical is glycine, the simplest aminoacid, synthesized by virtually all plants and animals and present in almost all the proteins. Its chemical properties are very well defined, but normally people do not think of stuff made by plants and animals as being chemical, because when people hear about chemicals they immediately think of man-made substances, usually toxic. Not so, not so...
Nuclear: for people who studied Latin at school, this is trivial. Nucleus comes from a Latin word meaning "core", therefore the nucleus (adj: nuclear) is basically the core of something, whether it is a cell or an atom. So scientists were quite confused when people were scared of taking a nuclear magnetic resonance (NMR); in the end, they changed the name to the friendlier definition of "magnetic resonance imaging" (MRI). This technique has nothing to do with radiation, but with the magnetic properties of the atomic nucleus. Radioactivity is nuclear, in a sense, because it is generated in the nucleus. The bad reputation probably comes from the "nuclear bomb", which uses the power harnessed in the atomic nuclei to wreck havoc. So when a journalist asked a geneticist to change "nuclear" with "of the nucleus", we all were a bit annoyed.
Aromatic: this is really funny! For many people, aromatic means that something has a very good smell... Aromatic herbs, aromatic gardens... But in chemistry, there is a whole category of compounds which are called aromatic and frankly, they stink! Have you ever tried to solve a moth invasion using naphthalene? I have (I had an invasion of carpet beetles) and my house stank for days and days... Aromatic compounds have very special characteristics and their chemistry takes many chapters in an organic chemistry textbook; the best way to describe them is by imagining very flat molecules (they are planar) with a very strong stability***.
* no carbon in feldspar; it is a rock that contains mostly silicon and aluminium. Yummy!
** it is an aromatic compound, but this one actually smells good!
*** for the most curious people, wikipedia has a very good article on aromaticity.
Thursday, March 8, 2007
Tuesday, February 27, 2007
Pills of... vitamins: fact #2
Here we are for the second episode of this very energetic saga (pardon me my bad pun). In the previous episode, we have seen our heroine prevailing over shaggy traffickers of natural vitamins.
In this post, I will also tell why, in part, but only in a minuscule part, I think the supporters of natural vitamins are right - and where again they're missing the target.
From a chemical point of view, it does not matter where a substance comes from - as long as two substances have the same chemical structure, they will have exactly the same properties. If I take carbon from the moon, it will have the same chemical properties of carbon on earth (maybe not the physical properties*). If I take methane from mars, it will behave exactly like the methane on earth. If I take vitamin c from a pill, it will be absolutely identical to the one synthesized by plants and animals**.
I concede there are some exceptions, of course. Vitamin E is a case in point: in commercial products there are two forms***, of which only one is active (they cannot be synthesized separately - animal and plants are smarter than humans and they can make only the active form); but why people mistrust scientists so much? Why don't people believe that only the active ingredient is counted? (Indeed, the labels talk about vitamin E equivalents)****.
But why the vitamins coming from food might offer some advantages to us?
Personally, I came to the conclusion that gorging myself on vitamins once a day might be not the best way to get my daily supply. You see, besides a couple of vitamins (A and D), the human body has no storage facilities for vitamins. If I eat 600 milligrams of vitamin c in the morning, but I only need 5 milligrams during that particular time, then the excess will be happily excreted with the waste material (in the form of pee). That's good, because a scientific paper some time ago showed that high concentration of vitamin c, especially in presence of iron (hey! my supplement contains 27 milligrams of iron!) could work as pro-oxidant - which means that it could actually make things worse, not better! But going back to the main issue, it means that 555 milligrams are literally wasted! Later in the day, I may need more vitamin c, but of course it is not available anywhere in my body, because it has been already disposed of! Dahh!
To counteract this problem, now it is possible to purchase slow-release vitamin c (I don't know whether other vitamins are available in slow-release form). My point is: why don't I simply eat more oranges? Say one orange every two hours? Fruit is tastier than pills, probably just as expensive (when buying it in the season), and it contains precious minerals and fiber... Besides, there are so many reports that other compounds in fruit and vegetables might be not just beneficial for our health, but actually necessary!
Of course, it is wise to take a pill whenever we feel we won't meet our daily requirements, say if we are travelling, or we have a cold...
Still, this argument does not justify the people who discredit food supplements, only to suggest exotic alternatives... Especially very expensive alternatives...
* a gross approximation is that chemistry deals with the "outside" of atoms and molecules - so the way they react with each other; physics deals with the "inside" of the atoms - so we don't include the properties of isotopes in our discussion: it is already complicated enough! (And not really relevant).
** also because a new commercial production line for vitamin c isolates the vitamin produced by friendly bugs - so even the vitamin c found in pills is technically coming from a biochemical source. I am not sure it reached the whole planet yet, though.
*** dl-alpha tocopherol is a mixture of d-alpha tocopherol and l-alpha tocopherol. They cannot be easily separated by conventional means, and anyway, the inactive form is harmless. It's simpler to leave it there.
**** not all scientists are after the money (actually, given the little salaries they receive, they're definitely not after the money)...
In this post, I will also tell why, in part, but only in a minuscule part, I think the supporters of natural vitamins are right - and where again they're missing the target.
From a chemical point of view, it does not matter where a substance comes from - as long as two substances have the same chemical structure, they will have exactly the same properties. If I take carbon from the moon, it will have the same chemical properties of carbon on earth (maybe not the physical properties*). If I take methane from mars, it will behave exactly like the methane on earth. If I take vitamin c from a pill, it will be absolutely identical to the one synthesized by plants and animals**.
I concede there are some exceptions, of course. Vitamin E is a case in point: in commercial products there are two forms***, of which only one is active (they cannot be synthesized separately - animal and plants are smarter than humans and they can make only the active form); but why people mistrust scientists so much? Why don't people believe that only the active ingredient is counted? (Indeed, the labels talk about vitamin E equivalents)****.
But why the vitamins coming from food might offer some advantages to us?
Personally, I came to the conclusion that gorging myself on vitamins once a day might be not the best way to get my daily supply. You see, besides a couple of vitamins (A and D), the human body has no storage facilities for vitamins. If I eat 600 milligrams of vitamin c in the morning, but I only need 5 milligrams during that particular time, then the excess will be happily excreted with the waste material (in the form of pee). That's good, because a scientific paper some time ago showed that high concentration of vitamin c, especially in presence of iron (hey! my supplement contains 27 milligrams of iron!) could work as pro-oxidant - which means that it could actually make things worse, not better! But going back to the main issue, it means that 555 milligrams are literally wasted! Later in the day, I may need more vitamin c, but of course it is not available anywhere in my body, because it has been already disposed of! Dahh!
To counteract this problem, now it is possible to purchase slow-release vitamin c (I don't know whether other vitamins are available in slow-release form). My point is: why don't I simply eat more oranges? Say one orange every two hours? Fruit is tastier than pills, probably just as expensive (when buying it in the season), and it contains precious minerals and fiber... Besides, there are so many reports that other compounds in fruit and vegetables might be not just beneficial for our health, but actually necessary!
Of course, it is wise to take a pill whenever we feel we won't meet our daily requirements, say if we are travelling, or we have a cold...
Still, this argument does not justify the people who discredit food supplements, only to suggest exotic alternatives... Especially very expensive alternatives...
* a gross approximation is that chemistry deals with the "outside" of atoms and molecules - so the way they react with each other; physics deals with the "inside" of the atoms - so we don't include the properties of isotopes in our discussion: it is already complicated enough! (And not really relevant).
** also because a new commercial production line for vitamin c isolates the vitamin produced by friendly bugs - so even the vitamin c found in pills is technically coming from a biochemical source. I am not sure it reached the whole planet yet, though.
*** dl-alpha tocopherol is a mixture of d-alpha tocopherol and l-alpha tocopherol. They cannot be easily separated by conventional means, and anyway, the inactive form is harmless. It's simpler to leave it there.
**** not all scientists are after the money (actually, given the little salaries they receive, they're definitely not after the money)...
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