There are good reasons to believe that enjoying yourself is beneficial for your health. Unhappiness has some severe downsides. Being depressed or stressed makes a wide range of medical conditions worse. The exact reasons for all this haven’t been teased out in the kind of detail that chemistry anoraks like me enjoy, but it seems to be to do with the workings of the immune system. The body reacts to your moods by producing hormones, and the ones it produces when you are happy seem to be ones that promote better health.
This is all very good news of course. It is particuarly good news for cosmetic chemists because it means that if we do our jobs well we can make the people who use our products not only look good, but feel good and therefore feel healthier. And knowing that makes us feel good and so we get to be healthier too. Don’t you just love science, eh?
This appealing train of thoughts was inspired by a rather unusual source. My good friend Dene Godfrey recently wrote a piece on Personal Care Truth defending the notion of ‘the dose makes the poison’. (Yes I have met Dene ladies, and its all true.) The dose makes the poison is a saying attributed to the legendary founder of modern pharmaceutics Paracelsus. It isn’t really all that complicated, it just states the obvious really. If you are going to murder someone with poison you need to give them a big enough dose to do so. On a practical basis this makes poison a pretty hopeless murder weapon. Very few things are toxic enough to kill someone outright reliably first time. Poison is more useful for writers of crime fiction than practitioners of crime fact. Agatha Christie probably saved quite a few lives by using ground glass as a murder weapon in some of her books. In reality it is completely harmless but there have been cases where people have tried to use it in real life with very disappointing results (from their point of view of course).
Anyway getting back to Dene’s article. He was responding to a post on her blog by Stacy Malkin criticising the notion of the dose makes the poison. As the leading light in the Campaign for Safe Cosmetics and with a scaremongering book to sell, Stacy must get fed up with people pointing out that the dose makes the poison. Not only must it get tedious, it also completely demolishes her case. Anyway Dene’s article very effectively reasserted that the dose does indeed make the poison. There wasn’t really anything more to add and the comments thread started to fill up with people agreeing with what Dene had written.
One person did try to change the subject by asking if Dene had heard of the Precautionary Principle. The Precautionary Principle hasn’t been around as long as the dose makes the poison. But once again it is pretty much a statement of the obvious. When you are doing something new you should aim to be cautious before acting on that new knowledge. This makes perfect sense and can be applied pretty widely, though for some reason it is particularly frequently cited when it comes to new chemicals. This is reasonably fair because some chemicals once released into the environment can be very persistent and once they are out there you can’t easily get them back again. It isn’t always appreciated by non-chemists that most man made chemicals are not very persistent, but nonethelss some are so you really do need to be cautious. We don’t want to have another case like that of lead in petrol for example.
But it is equally important to remember that deciding not to do something is as much a decision as deciding to do something. Withholding the benefits of a new chemical can be just as deadly as releasing one that turns out to have unexpected side effects. There is a very good example that everyone should know about. Ignaz Semmelweis was an Hungarian physician who noticed that death rates from surgery were considerably reduced if the surgeon washed his hands before carrying out the operation. This was before the germ theory had been developed, so he didn’t have any good explanation for why it should be so. As a consequence, his ideas were not accepted very widely. In fact Semmelweis himself probably died as the result of an infection contracted while being treated for septicaemia. That has got to have cheesed him off. The surgeons of his day were following the precautionary principle in the sense of avoiding exposing their patients to chemicals, but I don’t suppose many of them would have thanked them for it even if unlike poor old Ignaz they were still on two legs and able to do so.
Even the dose makes the poison can be applied in ways that give perverse results. Take for example the presence of lead in lipstick. If you have read my post on lead in lipstick you’ll know that there are some brands out that have been shown to contain a fraction of a part per million of lead. If you look at the levels in the lipstick and compare it to levels the body can comfortably cope with you quickly conclude that those levels are way below the level that could conceivably do any harm and so pronounce lipsticks to be safe. But the true situation is that the lead is bound up in insoluble minerals which are themselves coated with wax. Both of these facts make it almost impossible for the body to absorb the lead.
The dose makes the poison is a simplification that makes decisions easier but probably overall leads to exaggerating the dangers to which we are exposed. The precautionary principle is even worse. Applying the precautionary principle to our lipsticks you might say well the lead is at a low level and is in a form that can’t be absorbed, but as we can’t be sure that there isn’t some effect we don’t know about wouldn’t it be safer to avoid lipstick altogether. That is logical, but is it sensible? Given that wearing lipstick makes you feel good, and feeling good makes you healthier it could well be that following the precautionary principle in this case might in fact make you ill.
Having thought it over, I have decided to formulate my own principle. Be on the safe side, only use products if you are really sure you enjoy them.
